Prepare 2.169.0 runner release for GHES Alpha.

Bumps [acorn](https://github.com/acornjs/acorn) from 6.4.0 to 6.4.1.
- [Release notes](https://github.com/acornjs/acorn/releases)
- [Commits](https://github.com/acornjs/acorn/compare/6.4.0...6.4.1)

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

docs/adrs/0361-wrapper-action.md

@@ -0,0 +1,75 @@
+# ADR 361: Wrapper Action
+
+**Date**: 2020-03-06
+
+**Status**: Pending
+
+## Context
+
+In addition to action's regular execution, action author may wants their action has a chance to participate in:
+- Job initialize  
+  My Action will collect machine resource usage (CPU/RAM/Disk) during a workflow job execution, we need to start perf recorder at the begin of the job.
+- Job cleanup  
+  My Action will dirty local workspace or machine environment during execution, we need to cleanup these changes at the end of the job.  
+  Ex: `actions/checkout@v2` will write `github.token` into local `.git/config` during execution, it has post job cleanup defined to undo the changes.
+
+## Decision
+
+### Add `pre` and `post` execution to action
+
+Node Action Example:
+
+```yaml
+ name: 'My action with pre'
+ description: 'My action with pre'
+ runs:
+   using: 'node12'
+   pre: 'setup.js'
+   pre-if: 'success()' // Optional
+   main: 'index.js'
+   post: 'cleanup.js'
+   post-if: 'success()' // Optional
+```
+
+Container Action Example:
+
+```yaml
+ name: 'My action with pre'
+ description: 'My action with pre'
+ runs:
+   using: 'docker'
+   image: 'mycontainer:latest'
+   pre-entrypoint: 'setup.sh'
+   pre-if: 'success()' // Optional
+   entrypoint: 'entrypoint.sh'
+   post-entrypoint: 'cleanup.sh'
+   post-if: 'success()' // Optional
+```
+
+Both `pre` and `post` will has default `pre-if/post-if` sets to `always()`.  
+Setting `pre` to `always()` will make sure no matter what condition evaluate result the `main` gets at runtime, the `pre` has always run already.   
+`pre` executes in order of how the steps are defined.  
+`pre` will always be added to job steps list during job setup.  
+> Action referenced from local repository (`./my-action`) won't get `pre` setup correctly since the repository haven't checkout during job initialize.  
+> We can't use GitHub api to download the repository since there is a about 3 mins delay between `git push` and the new commit available to download using GitHub api.
+
+`post` will be pushed into a `poststeps` stack lazily when the action's `pre` or `main` execution passed `if` condition check and about to run, you can't have an action that only contains a `post`, we will pop and run each `post` after all `pre` and `main` finished.
+> Currently `post` works for both repository action (`org/repo@v1`) and local action (`./my-action`)
+
+Valid action:
+- only has `main`
+- has `pre` and `main`
+- has `main` and `post`
+- has `pre`, `main` and `post`
+
+Invalid action:
+- only has `pre`
+- only has `post`
+- has `pre` and `post`
+
+Potential downside of introducing `pre`:
+
+- Extra magic wrt step order. Users should control the step order. Especially when we introduce templates.  
+- Eliminates the possibility to lazily download the action tarball, since `pre` always run by default, we have to download the tarball to check whether action defined a `pre`  
+- `pre` doesn't work with local action, we suggested customer use local action for testing their action changes, ex CI for their action, to avoid delay between `git push` and GitHub repo tarball download api.  
+- Condition on the `pre` can't be controlled using dynamic step outputs. `pre` executes too early.

docs/adrs/0397-runner-registration-labels.md

@@ -0,0 +1,56 @@
+# ADR 0397: Support adding custom labels during runner config
+**Date**: 2020-03-30
+
+**Status**: Approved
+
+## Context
+
+Since configuring self-hosted runners is commonly automated via scripts, the labels need to be able to be created during configuration.  The runner currently registers the built-in labels (os, arch) during registration but does not accept labels via command line args to extend the set registered.
+
+See Issue: https://github.com/actions/runner/issues/262
+
+This is another version of [ADR275](https://github.com/actions/runner/pull/275)
+
+## Decision
+
+This ADR proposes that we add a `--labels` option to `config`, which could be used to add custom additional labels to the configured runner.
+
+For example, to add a single extra label the operator could run:
+```bash
+./config.sh --labels mylabel
+```
+> Note: the current runner command line parsing and envvar override algorithm only supports a single argument (key).
+
+This would add the label `mylabel` to the runner, and enable users to select the runner in their workflow using this label:
+```yaml
+runs-on: [self-hosted, mylabel]
+```
+
+To add multiple labels the operator could run:
+```bash
+./config.sh --labels mylabel,anotherlabel
+```
+> Note: the current runner command line parsing and envvar override algorithm only supports a single argument (key).
+
+This would add the label `mylabel` and `anotherlabel` to the runner, and enable users to select the runner in their workflow using this label:
+```yaml
+runs-on: [self-hosted, mylabel, anotherlabel]
+```
+
+It would not be possible to remove labels from an existing runner using `config.sh`, instead labels would have to be removed using the GitHub UI.
+
+The labels argument will split on commas, trim and discard empty strings.  That effectively means don't use commans in unattended config label names.  Alternatively we could choose to escape commans but it's a nice to have.
+
+## Replace
+
+If an existing runner exists and the option to replace is chosen (interactively of via unattend as in this scenario), then the labels will be replaced / overwritten (not merged).
+
+## Overriding built-in labels
+
+Note that it is possible to register "built-in" hosted labels like `ubuntu-latest` and is not considered an error.  This is an effective way for the org / runner admin to dictate by policy through registration that this set of runners will be used without having to edit all the workflow files now and in the future.
+
+We will also not make other restrictions such as limiting explicitly adding os / arch labels and validating.  We will assume that explicit labels were added for a reason and not restricting offers the most flexibility and future proofing / compat.
+
+## Consequences
+
+The ability to add custom labels to a self-hosted runner would enable most scenarios where job runner selection based on runner capabilities or characteristics are required.

releaseNote.md

@@ -1,27 +1,11 @@
 ## Features
-  - Expose whether debug is on/off via RUNNER_DEBUG. (#253)
-  - Upload log on runner when worker get killed due to cancellation timeout. (#255)
-  - Update config.sh/cmd --help documentation (#282) 
-  - Set http_proxy and related env vars for job/service containers (#304)
-  - Set both http_proxy and HTTP_PROXY env for runner/worker processes. (#298)
-
+  - Runner support for GHES Alpha (#381 #386 #390 #393 $401) 
+  - Allow secrets context in Container.env (#388)
 ## Bugs
-  - Verify runner Windows service hash started successfully after configuration (#236)
-  - Detect source file path in L0 without using env. (#257)
-  - Handle escaped '%' in commands data section (#200)
-  - Allow container to be null/empty during matrix expansion (#266)
-  - Translate problem matcher file to host path (#272)
-  - Change hashFiles() expression function to use @actions/glob. (#268)
-  - Default post-job action's condition to always(). (#293)
-  - Support action.yaml file as action's entry file (#288) 
-  - Trace javascript action exit code to debug instead of user logs (#290)
-  - Change prompt message when removing a runner to lines up with GitHub.com UI (#303) 
-  - Include step.env as part of env context. (#300)
-  - Update Base64 Encoders to deal with suffixes (#284)
-
+  - Raise warning when volume mount root. (#413)
+  - Fix typo (#394)
 ## Misc
-  - Move .sln file under ./src (#238)
-  - Treat warnings as errors during compile (#249) 
+  - N/A
 
 ## Windows x64
 We recommend configuring the runner in a root folder of the Windows drive (e.g. "C:\actions-runner"). This will help avoid issues related to service identity folder permissions and long file path restrictions on Windows

src/Misc/dotnet-install.sh

@@ -172,7 +172,7 @@ get_current_os_name() {
         return 0
     elif [ "$uname" = "FreeBSD" ]; then
         echo "freebsd"
-        return 0        
+        return 0
     elif [ "$uname" = "Linux" ]; then
         local linux_platform_name
         linux_platform_name="$(get_linux_platform_name)" || { echo "linux" && return 0 ; }
@@ -728,11 +728,12 @@ downloadcurl() {
     # Append feed_credential as late as possible before calling curl to avoid logging feed_credential
     remote_path="${remote_path}${feed_credential}"
 
+    local curl_options="--retry 20 --retry-delay 2 --connect-timeout 15 -sSL -f --create-dirs "
     local failed=false
     if [ -z "$out_path" ]; then
-        curl --retry 10 -sSL -f --create-dirs "$remote_path" || failed=true
+        curl $curl_options "$remote_path" || failed=true
     else
-        curl --retry 10 -sSL -f --create-dirs -o "$out_path" "$remote_path" || failed=true
+        curl $curl_options -o "$out_path" "$remote_path" || failed=true
     fi
     if [ "$failed" = true ]; then
         say_verbose "Curl download failed"
@@ -748,12 +749,12 @@ downloadwget() {
 
     # Append feed_credential as late as possible before calling wget to avoid logging feed_credential
     remote_path="${remote_path}${feed_credential}"
-
+    local wget_options="--tries 20 --waitretry 2 --connect-timeout 15 "
     local failed=false
     if [ -z "$out_path" ]; then
-        wget -q --tries 10 -O - "$remote_path" || failed=true
+        wget -q $wget_options -O - "$remote_path" || failed=true
     else
-        wget --tries 10 -O "$out_path" "$remote_path" || failed=true
+        wget $wget_options -O "$out_path" "$remote_path" || failed=true
     fi
     if [ "$failed" = true ]; then
         say_verbose "Wget download failed"

src/Misc/expressionFunc/hashFiles/package.json

@@ -27,7 +27,7 @@
     "@types/node": "^12.7.12",
     "@typescript-eslint/parser": "^2.8.0",
     "@zeit/ncc": "^0.20.5",
-    "eslint": "^5.16.0",
+    "eslint": "^6.8.0",
     "eslint-plugin-github": "^2.0.0",
     "prettier": "^1.19.1",
     "typescript": "^3.6.4"

src/Runner.Common/ConfigurationStore.cs

@@ -15,6 +15,9 @@ namespace GitHub.Runner.Common
     [DataContract]
     public sealed class RunnerSettings
     {
+        [DataMember(Name = "IsHostedServer", EmitDefaultValue = false)]
+        private bool? _isHostedServer;
+
         [DataMember(EmitDefaultValue = false)]
         public int AgentId { get; set; }
 
@@ -42,6 +45,21 @@ namespace GitHub.Runner.Common
         [DataMember(EmitDefaultValue = false)]
         public string MonitorSocketAddress { get; set; }
 
+        [IgnoreDataMember]
+        public bool IsHostedServer
+        {
+            get
+            {
+                // Old runners do not have this property. Hosted runners likely don't have this property either.
+                return _isHostedServer ?? true;
+            }
+
+            set
+            {
+                _isHostedServer = value;
+            }
+        }
+
         /// <summary>
         // Computed property for convenience. Can either return:
         // 1. If runner was configured at the repo level, returns something like: "myorg/myrepo"
@@ -69,6 +87,15 @@ namespace GitHub.Runner.Common
                 return repoOrOrgName;
             }
         }
+
+        [OnSerializing]
+        private void OnSerializing(StreamingContext context)
+        {
+            if (_isHostedServer.HasValue && _isHostedServer.Value)
+            {
+                _isHostedServer = null;
+            }
+        }
     }
 
     [ServiceLocator(Default = typeof(ConfigurationStore))]

src/Runner.Listener/Configuration/ConfigurationManager.cs

@@ -86,7 +86,6 @@ namespace GitHub.Runner.Listener.Configuration
 
             RunnerSettings runnerSettings = new RunnerSettings();
 
-            bool isHostedServer = false;
             // Loop getting url and creds until you can connect
             ICredentialProvider credProvider = null;
             VssCredentials creds = null;
@@ -95,8 +94,7 @@ namespace GitHub.Runner.Listener.Configuration
             {
                 // Get the URL
                 var inputUrl = command.GetUrl();
-                if (!inputUrl.Contains("github.com", StringComparison.OrdinalIgnoreCase) &&
-                    !inputUrl.Contains("github.localhost", StringComparison.OrdinalIgnoreCase))
+                if (inputUrl.Contains("codedev.ms", StringComparison.OrdinalIgnoreCase))
                 {
                     runnerSettings.ServerUrl = inputUrl;
                     // Get the credentials
@@ -117,7 +115,7 @@ namespace GitHub.Runner.Listener.Configuration
                 try
                 {
                     // Determine the service deployment type based on connection data. (Hosted/OnPremises)
-                    isHostedServer = await IsHostedServer(runnerSettings.ServerUrl, creds);
+                    runnerSettings.IsHostedServer = runnerSettings.GitHubUrl == null || IsHostedServer(new UriBuilder(runnerSettings.GitHubUrl));
 
                     // Validate can connect.
                     await _runnerServer.ConnectAsync(new Uri(runnerSettings.ServerUrl), creds);
@@ -199,7 +197,7 @@ namespace GitHub.Runner.Listener.Configuration
                 }
                 else
                 {
-                    // Create a new agent. 
+                    // Create a new agent.
                     agent = CreateNewAgent(runnerSettings.AgentName, publicKey);
 
                     try
@@ -248,14 +246,6 @@ namespace GitHub.Runner.Listener.Configuration
             {
                 UriBuilder configServerUrl = new UriBuilder(runnerSettings.ServerUrl);
                 UriBuilder oauthEndpointUrlBuilder = new UriBuilder(agent.Authorization.AuthorizationUrl);
-                if (!isHostedServer && Uri.Compare(configServerUrl.Uri, oauthEndpointUrlBuilder.Uri, UriComponents.SchemeAndServer, UriFormat.Unescaped, StringComparison.OrdinalIgnoreCase) != 0)
-                {
-                    oauthEndpointUrlBuilder.Scheme = configServerUrl.Scheme;
-                    oauthEndpointUrlBuilder.Host = configServerUrl.Host;
-                    oauthEndpointUrlBuilder.Port = configServerUrl.Port;
-                    Trace.Info($"Set oauth endpoint url's scheme://host:port component to match runner configure url's scheme://host:port: '{oauthEndpointUrlBuilder.Uri.AbsoluteUri}'.");
-                }
-
                 var credentialData = new CredentialData
                 {
                     Scheme = Constants.Configuration.OAuth,
@@ -291,7 +281,7 @@ namespace GitHub.Runner.Listener.Configuration
             {
                 // there are two exception messages server send that indicate clock skew.
                 // 1. The bearer token expired on {jwt.ValidTo}. Current server time is {DateTime.UtcNow}.
-                // 2. The bearer token is not valid until {jwt.ValidFrom}. Current server time is {DateTime.UtcNow}.                
+                // 2. The bearer token is not valid until {jwt.ValidFrom}. Current server time is {DateTime.UtcNow}.
                 Trace.Error("Catch exception during test agent connection.");
                 Trace.Error(ex);
                 throw new Exception("The local machine's clock may be out of sync with the server time by more than five minutes. Please sync your clock with your domain or internet time and try again.");
@@ -381,7 +371,6 @@ namespace GitHub.Runner.Listener.Configuration
                     }
 
                     // Determine the service deployment type based on connection data. (Hosted/OnPremises)
-                    bool isHostedServer = await IsHostedServer(settings.ServerUrl, creds);
                     await _runnerServer.ConnectAsync(new Uri(settings.ServerUrl), creds);
 
                     var agents = await _runnerServer.GetAgentsAsync(settings.PoolId, settings.AgentName);
@@ -404,7 +393,7 @@ namespace GitHub.Runner.Listener.Configuration
                     _term.WriteLine("Cannot connect to server, because config files are missing. Skipping removing runner from the server.");
                 }
 
-                //delete credential config files               
+                //delete credential config files
                 currentAction = "Removing .credentials";
                 if (hasCredentials)
                 {
@@ -418,7 +407,7 @@ namespace GitHub.Runner.Listener.Configuration
                     _term.WriteLine("Does not exist. Skipping " + currentAction);
                 }
 
-                //delete settings config file                
+                //delete settings config file
                 currentAction = "Removing .runner";
                 if (isConfigured)
                 {
@@ -498,31 +487,26 @@ namespace GitHub.Runner.Listener.Configuration
             return agent;
         }
 
-        private async Task<bool> IsHostedServer(string serverUrl, VssCredentials credentials)
+        private bool IsHostedServer(UriBuilder gitHubUrl)
         {
-            // Determine the service deployment type based on connection data. (Hosted/OnPremises)
-            var locationServer = HostContext.GetService<ILocationServer>();
-            VssConnection connection = VssUtil.CreateConnection(new Uri(serverUrl), credentials);
-            await locationServer.ConnectAsync(connection);
-            try
-            {
-                var connectionData = await locationServer.GetConnectionDataAsync();
-                Trace.Info($"Server deployment type: {connectionData.DeploymentType}");
-                return connectionData.DeploymentType.HasFlag(DeploymentFlags.Hosted);
-            }
-            catch (Exception ex)
-            {
-                // Since the DeploymentType is Enum, deserialization exception means there is a new Enum member been added.
-                // It's more likely to be Hosted since OnPremises is always behind and customer can update their agent if are on-prem
-                Trace.Error(ex);
-                return true;
-            }
+            return string.Equals(gitHubUrl.Host, "github.com", StringComparison.OrdinalIgnoreCase) ||
+                string.Equals(gitHubUrl.Host, "www.github.com", StringComparison.OrdinalIgnoreCase) ||
+                string.Equals(gitHubUrl.Host, "github.localhost", StringComparison.OrdinalIgnoreCase);
         }
 
         private async Task<GitHubAuthResult> GetTenantCredential(string githubUrl, string githubToken, string runnerEvent)
         {
+            var githubApiUrl = "";
             var gitHubUrlBuilder = new UriBuilder(githubUrl);
-            var githubApiUrl = $"{gitHubUrlBuilder.Scheme}://api.{gitHubUrlBuilder.Host}/actions/runner-registration";
+            if (IsHostedServer(gitHubUrlBuilder))
+            {
+                githubApiUrl = $"{gitHubUrlBuilder.Scheme}://api.{gitHubUrlBuilder.Host}/actions/runner-registration";
+            }
+            else
+            {
+                githubApiUrl = $"{gitHubUrlBuilder.Scheme}://{gitHubUrlBuilder.Host}/api/v3/actions/runner-registration";
+            }
+
             using (var httpClientHandler = HostContext.CreateHttpClientHandler())
             using (var httpClient = new HttpClient(httpClientHandler))
             {

src/Runner.Worker/ActionManager.cs

@@ -51,15 +51,21 @@ namespace GitHub.Runner.Worker
             List<JobExtensionRunner> containerSetupSteps = new List<JobExtensionRunner>();
             IEnumerable<Pipelines.ActionStep> actions = steps.OfType<Pipelines.ActionStep>();
 
-            // TODO: Depreciate the PREVIEW_ACTION_TOKEN
+            // TODO: Deprecate the PREVIEW_ACTION_TOKEN
             // Log even if we aren't using it to ensure users know.
             if (!string.IsNullOrEmpty(executionContext.Variables.Get("PREVIEW_ACTION_TOKEN")))
             {
-                executionContext.Warning("The 'PREVIEW_ACTION_TOKEN' secret is depreciated. Please remove it from the repository's secrets");
+                executionContext.Warning("The 'PREVIEW_ACTION_TOKEN' secret is deprecated. Please remove it from the repository's secrets");
             }
 
-            // Clear the cache (local runner)
-            IOUtil.DeleteDirectory(HostContext.GetDirectory(WellKnownDirectory.Actions), executionContext.CancellationToken);
+            // Clear the cache (for self-hosted runners)
+            // Note, temporarily avoid this step for the on-premises product, to avoid rate limiting.
+            var configurationStore = HostContext.GetService<IConfigurationStore>();
+            var isHostedServer = configurationStore.GetSettings().IsHostedServer;
+            if (isHostedServer)
+            {
+                IOUtil.DeleteDirectory(HostContext.GetDirectory(WellKnownDirectory.Actions), executionContext.CancellationToken);
+            }
 
             foreach (var action in actions)
             {
@@ -448,7 +454,8 @@ namespace GitHub.Runner.Worker
             ArgUtil.NotNullOrEmpty(repositoryReference.Ref, nameof(repositoryReference.Ref));
 
             string destDirectory = Path.Combine(HostContext.GetDirectory(WellKnownDirectory.Actions), repositoryReference.Name.Replace(Path.AltDirectorySeparatorChar, Path.DirectorySeparatorChar), repositoryReference.Ref);
-            if (File.Exists(destDirectory + ".completed"))
+            string watermarkFile = destDirectory + ".completed";
+            if (File.Exists(watermarkFile))
             {
                 executionContext.Debug($"Action '{repositoryReference.Name}@{repositoryReference.Ref}' already downloaded at '{destDirectory}'.");
                 return;
@@ -498,24 +505,33 @@ namespace GitHub.Runner.Worker
                             using (var httpClientHandler = HostContext.CreateHttpClientHandler())
                             using (var httpClient = new HttpClient(httpClientHandler))
                             {
-                                var authToken = Environment.GetEnvironmentVariable("_GITHUB_ACTION_TOKEN");
-                                if (string.IsNullOrEmpty(authToken))
+                                var configurationStore = HostContext.GetService<IConfigurationStore>();
+                                var isHostedServer = configurationStore.GetSettings().IsHostedServer;
+                                if (isHostedServer)
                                 {
-                                    // TODO: Depreciate the PREVIEW_ACTION_TOKEN
-                                    authToken = executionContext.Variables.Get("PREVIEW_ACTION_TOKEN");
-                                }
+                                    var authToken = Environment.GetEnvironmentVariable("_GITHUB_ACTION_TOKEN");
+                                    if (string.IsNullOrEmpty(authToken))
+                                    {
+                                        // TODO: Deprecate the PREVIEW_ACTION_TOKEN
+                                        authToken = executionContext.Variables.Get("PREVIEW_ACTION_TOKEN");
+                                    }
 
-                                if (!string.IsNullOrEmpty(authToken))
-                                {
-                                    HostContext.SecretMasker.AddValue(authToken);
-                                    var base64EncodingToken = Convert.ToBase64String(Encoding.UTF8.GetBytes($"PAT:{authToken}"));
-                                    httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", base64EncodingToken);
+                                    if (!string.IsNullOrEmpty(authToken))
+                                    {
+                                        HostContext.SecretMasker.AddValue(authToken);
+                                        var base64EncodingToken = Convert.ToBase64String(Encoding.UTF8.GetBytes($"PAT:{authToken}"));
+                                        httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", base64EncodingToken);
+                                    }
+                                    else
+                                    {
+                                        var accessToken = executionContext.GetGitHubContext("token");
+                                        var base64EncodingToken = Convert.ToBase64String(Encoding.UTF8.GetBytes($"x-access-token:{accessToken}"));
+                                        httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", base64EncodingToken);
+                                    }
                                 }
                                 else
                                 {
-                                    var accessToken = executionContext.GetGitHubContext("token");
-                                    var base64EncodingToken = Convert.ToBase64String(Encoding.UTF8.GetBytes($"x-access-token:{accessToken}"));
-                                    httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", base64EncodingToken);
+                                    // Intentionally empty. Temporary for GHES alpha release, download from dotcom unauthenticated.
                                 }
 
                                 httpClient.DefaultRequestHeaders.UserAgent.Add(HostContext.UserAgent);
@@ -610,7 +626,7 @@ namespace GitHub.Runner.Worker
                 }
 
                 Trace.Verbose("Create watermark file indicate action download succeed.");
-                File.WriteAllText(destDirectory + ".completed", DateTime.UtcNow.ToString());
+                File.WriteAllText(watermarkFile, DateTime.UtcNow.ToString());
 
                 executionContext.Debug($"Archive '{archiveFile}' has been unzipped into '{destDirectory}'.");
                 Trace.Info("Finished getting action repository.");

src/Runner.Worker/ActionManifestManager.cs

@@ -22,11 +22,11 @@ namespace GitHub.Runner.Worker
     {
         ActionDefinitionData Load(IExecutionContext executionContext, string manifestFile);
 
-        List<string> EvaluateContainerArguments(IExecutionContext executionContext, SequenceToken token, IDictionary<string, PipelineContextData> contextData);
+        List<string> EvaluateContainerArguments(IExecutionContext executionContext, SequenceToken token, IDictionary<string, PipelineContextData> extraExpressionValues);
 
-        Dictionary<string, string> EvaluateContainerEnvironment(IExecutionContext executionContext, MappingToken token, IDictionary<string, PipelineContextData> contextData);
+        Dictionary<string, string> EvaluateContainerEnvironment(IExecutionContext executionContext, MappingToken token, IDictionary<string, PipelineContextData> extraExpressionValues);
 
-        string EvaluateDefaultInput(IExecutionContext executionContext, string inputName, TemplateToken token, IDictionary<string, PipelineContextData> contextData);
+        string EvaluateDefaultInput(IExecutionContext executionContext, string inputName, TemplateToken token);
     }
 
     public sealed class ActionManifestManager : RunnerService, IActionManifestManager
@@ -54,7 +54,7 @@ namespace GitHub.Runner.Worker
 
         public ActionDefinitionData Load(IExecutionContext executionContext, string manifestFile)
         {
-            var context = CreateContext(executionContext, null);
+            var context = CreateContext(executionContext);
             ActionDefinitionData actionDefinition = new ActionDefinitionData();
             try
             {
@@ -133,13 +133,13 @@ namespace GitHub.Runner.Worker
         public List<string> EvaluateContainerArguments(
             IExecutionContext executionContext,
             SequenceToken token,
-            IDictionary<string, PipelineContextData> contextData)
+            IDictionary<string, PipelineContextData> extraExpressionValues)
         {
             var result = new List<string>();
 
             if (token != null)
             {
-                var context = CreateContext(executionContext, contextData);
+                var context = CreateContext(executionContext, extraExpressionValues);
                 try
                 {
                     var evaluateResult = TemplateEvaluator.Evaluate(context, "container-runs-args", token, 0, null, omitHeader: true);
@@ -172,13 +172,13 @@ namespace GitHub.Runner.Worker
         public Dictionary<string, string> EvaluateContainerEnvironment(
             IExecutionContext executionContext,
             MappingToken token,
-            IDictionary<string, PipelineContextData> contextData)
+            IDictionary<string, PipelineContextData> extraExpressionValues)
         {
             var result = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
 
             if (token != null)
             {
-                var context = CreateContext(executionContext, contextData);
+                var context = CreateContext(executionContext, extraExpressionValues);
                 try
                 {
                     var evaluateResult = TemplateEvaluator.Evaluate(context, "container-runs-env", token, 0, null, omitHeader: true);
@@ -216,13 +216,12 @@ namespace GitHub.Runner.Worker
         public string EvaluateDefaultInput(
             IExecutionContext executionContext,
             string inputName,
-            TemplateToken token,
-            IDictionary<string, PipelineContextData> contextData)
+            TemplateToken token)
         {
             string result = "";
             if (token != null)
             {
-                var context = CreateContext(executionContext, contextData);
+                var context = CreateContext(executionContext);
                 try
                 {
                     var evaluateResult = TemplateEvaluator.Evaluate(context, "input-default-context", token, 0, null, omitHeader: true);
@@ -247,7 +246,7 @@ namespace GitHub.Runner.Worker
 
         private TemplateContext CreateContext(
             IExecutionContext executionContext,
-            IDictionary<string, PipelineContextData> contextData)
+            IDictionary<string, PipelineContextData> extraExpressionValues = null)
         {
             var result = new TemplateContext
             {
@@ -261,14 +260,27 @@ namespace GitHub.Runner.Worker
                 TraceWriter = executionContext.ToTemplateTraceWriter(),
             };
 
-            if (contextData?.Count > 0)
+            // Expression values from execution context
+            foreach (var pair in executionContext.ExpressionValues)
             {
-                foreach (var pair in contextData)
+                result.ExpressionValues[pair.Key] = pair.Value;
+            }
+
+            // Extra expression values
+            if (extraExpressionValues?.Count > 0)
+            {
+                foreach (var pair in extraExpressionValues)
                 {
                     result.ExpressionValues[pair.Key] = pair.Value;
                 }
             }
 
+            // Expression functions from execution context
+            foreach (var item in executionContext.ExpressionFunctions)
+            {
+                result.ExpressionFunctions.Add(item);
+            }
+
             // Add the file table
             if (_fileTable?.Count > 0)
             {

src/Runner.Worker/ActionRunner.cs

@@ -26,7 +26,7 @@ namespace GitHub.Runner.Worker
     public interface IActionRunner : IStep, IRunnerService
     {
         ActionRunStage Stage { get; set; }
-        Boolean TryEvaluateDisplayName(DictionaryContextData contextData, IExecutionContext context);
+        bool TryEvaluateDisplayName(DictionaryContextData contextData, IExecutionContext context);
         Pipelines.ActionStep Action { get; set; }
     }
 
@@ -142,7 +142,7 @@ namespace GitHub.Runner.Worker
             // Load the inputs.
             ExecutionContext.Debug("Loading inputs");
             var templateEvaluator = ExecutionContext.ToPipelineTemplateEvaluator();
-            var inputs = templateEvaluator.EvaluateStepInputs(Action.Inputs, ExecutionContext.ExpressionValues);
+            var inputs = templateEvaluator.EvaluateStepInputs(Action.Inputs, ExecutionContext.ExpressionValues, ExecutionContext.ExpressionFunctions);
 
             foreach (KeyValuePair<string, string> input in inputs)
             {
@@ -162,13 +162,7 @@ namespace GitHub.Runner.Worker
                     string key = input.Key.AssertString("action input name").Value;
                     if (!inputs.ContainsKey(key))
                     {
-                        var evaluateContext = new Dictionary<string, PipelineContextData>(StringComparer.OrdinalIgnoreCase);
-                        foreach (var data in ExecutionContext.ExpressionValues)
-                        {
-                            evaluateContext[data.Key] = data.Value;
-                        }
-
-                        inputs[key] = manifestManager.EvaluateDefaultInput(ExecutionContext, key, input.Value, evaluateContext);
+                        inputs[key] = manifestManager.EvaluateDefaultInput(ExecutionContext, key, input.Value);
                     }
                 }
             }
@@ -293,10 +287,14 @@ namespace GitHub.Runner.Worker
                 return displayName;
             }
             // Try evaluating fully
-            var templateEvaluator = context.ToPipelineTemplateEvaluator();
             try
             {
-                didFullyEvaluate = templateEvaluator.TryEvaluateStepDisplayName(tokenToParse, contextData, out displayName);
+                if (tokenToParse.CheckHasRequiredContext(contextData, context.ExpressionFunctions))
+                {
+                    var templateEvaluator = context.ToPipelineTemplateEvaluator();
+                    displayName = templateEvaluator.EvaluateStepDisplayName(tokenToParse, contextData, context.ExpressionFunctions);
+                    didFullyEvaluate = true;
+                }
             }
             catch (TemplateValidationException e)
             {

src/Runner.Worker/Container/ContainerInfo.cs

@@ -61,6 +61,7 @@ namespace GitHub.Runner.Worker.Container
                 foreach (var volume in container.Volumes)
                 {
                     UserMountVolumes[volume] = volume;
+                    MountVolumes.Add(new MountVolume(volume));
                 }
             }
 

src/Runner.Worker/Container/DockerCommandManager.cs

@@ -130,6 +130,13 @@ namespace GitHub.Runner.Worker.Container
             // Watermark for GitHub Action environment
             dockerOptions.Add("-e GITHUB_ACTIONS=true");
 
+            // Set CI=true when no one else already set it.
+            // CI=true is common set in most CI provider in GitHub
+            if (!container.ContainerEnvironmentVariables.ContainsKey("CI"))
+            {
+                dockerOptions.Add("-e CI=true");
+            }
+
             foreach (var volume in container.MountVolumes)
             {
                 // replace `"` with `\"` and add `"{0}"` to all path.
@@ -189,6 +196,13 @@ namespace GitHub.Runner.Worker.Container
             // Watermark for GitHub Action environment
             dockerOptions.Add("-e GITHUB_ACTIONS=true");
 
+            // Set CI=true when no one else already set it.
+            // CI=true is common set in most CI provider in GitHub
+            if (!container.ContainerEnvironmentVariables.ContainsKey("CI"))
+            {
+                dockerOptions.Add("-e CI=true");
+            }
+
             if (!string.IsNullOrEmpty(container.ContainerEntryPoint))
             {
                 dockerOptions.Add($"--entrypoint \"{container.ContainerEntryPoint}\"");

src/Runner.Worker/ContainerOperationProvider.cs

@@ -47,7 +47,7 @@ namespace GitHub.Runner.Worker
                                                 condition: $"{PipelineTemplateConstants.Always}()",
                                                 displayName: "Stop containers",
                                                 data: data);
-            
+
             executionContext.Debug($"Register post job cleanup for stopping/deleting containers.");
             executionContext.RegisterPostJobStep(nameof(StopContainersAsync), postJobStep);
 
@@ -180,6 +180,11 @@ namespace GitHub.Runner.Worker
             foreach (var volume in container.UserMountVolumes)
             {
                 Trace.Info($"User provided volume: {volume.Value}");
+                var mount = new MountVolume(volume.Value);
+                if (string.Equals(mount.SourceVolumePath, "/", StringComparison.OrdinalIgnoreCase))
+                {
+                    executionContext.Warning($"Volume mount {volume.Value} is going to mount '/' into the container which may cause file ownership change in the entire file system and cause Actions Runner to lose permission to access the disk.");
+                }
             }
 
             // Pull down docker image with retry up to 3 times

src/Runner.Worker/ExecutionContext.cs

@@ -1,14 +1,15 @@
 using System;
+using System.Collections;
 using System.Collections.Generic;
 using System.Collections.Specialized;
 using System.Globalization;
 using System.IO;
 using System.Linq;
+using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 using System.Web;
-using GitHub.Runner.Worker.Container;
-using GitHub.Services.WebApi;
+using GitHub.DistributedTask.Expressions2;
 using GitHub.DistributedTask.Pipelines;
 using GitHub.DistributedTask.Pipelines.ContextData;
 using GitHub.DistributedTask.Pipelines.ObjectTemplating;
@@ -16,12 +17,11 @@ using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Common.Util;
 using GitHub.Runner.Common;
 using GitHub.Runner.Sdk;
+using GitHub.Runner.Worker.Container;
+using GitHub.Services.WebApi;
 using Newtonsoft.Json;
-using System.Text;
-using System.Collections;
 using ObjectTemplating = GitHub.DistributedTask.ObjectTemplating;
 using Pipelines = GitHub.DistributedTask.Pipelines;
-using GitHub.DistributedTask.Expressions2;
 
 namespace GitHub.Runner.Worker
 {
@@ -48,12 +48,14 @@ namespace GitHub.Runner.Worker
         PlanFeatures Features { get; }
         Variables Variables { get; }
         Dictionary<string, string> IntraActionState { get; }
+        IDictionary<String, IDictionary<String, String>> JobDefaults { get; }
         Dictionary<string, VariableValue> JobOutputs { get; }
         IDictionary<String, String> EnvironmentVariables { get; }
         IDictionary<String, ContextScope> Scopes { get; }
         IList<String> FileTable { get; }
         StepsContext StepsContext { get; }
         DictionaryContextData ExpressionValues { get; }
+        IList<IFunctionInfo> ExpressionFunctions { get; }
         List<string> PrependPath { get; }
         ContainerInfo Container { get; set; }
         List<ContainerInfo> ServiceContainers { get; }
@@ -140,12 +142,14 @@ namespace GitHub.Runner.Worker
         public List<ServiceEndpoint> Endpoints { get; private set; }
         public Variables Variables { get; private set; }
         public Dictionary<string, string> IntraActionState { get; private set; }
+        public IDictionary<String, IDictionary<String, String>> JobDefaults { get; private set; }
         public Dictionary<string, VariableValue> JobOutputs { get; private set; }
         public IDictionary<String, String> EnvironmentVariables { get; private set; }
         public IDictionary<String, ContextScope> Scopes { get; private set; }
         public IList<String> FileTable { get; private set; }
         public StepsContext StepsContext { get; private set; }
         public DictionaryContextData ExpressionValues { get; } = new DictionaryContextData();
+        public IList<IFunctionInfo> ExpressionFunctions { get; } = new List<IFunctionInfo>();
         public bool WriteDebug { get; private set; }
         public List<string> PrependPath { get; private set; }
         public ContainerInfo Container { get; set; }
@@ -270,6 +274,7 @@ namespace GitHub.Runner.Worker
                 child.IntraActionState = intraActionState;
             }
             child.EnvironmentVariables = EnvironmentVariables;
+            child.JobDefaults = JobDefaults;
             child.Scopes = Scopes;
             child.FileTable = FileTable;
             child.StepsContext = StepsContext;
@@ -277,6 +282,10 @@ namespace GitHub.Runner.Worker
             {
                 child.ExpressionValues[pair.Key] = pair.Value;
             }
+            foreach (var item in ExpressionFunctions)
+            {
+                child.ExpressionFunctions.Add(item);
+            }
             child._cancellationTokenSource = new CancellationTokenSource();
             child.WriteDebug = WriteDebug;
             child._parentExecutionContext = this;
@@ -565,6 +574,9 @@ namespace GitHub.Runner.Worker
             // Environment variables shared across all actions
             EnvironmentVariables = new Dictionary<string, string>(VarUtil.EnvironmentVariableKeyComparer);
 
+            // Job defaults shared across all actions
+            JobDefaults = new Dictionary<string, IDictionary<string, string>>(StringComparer.OrdinalIgnoreCase);
+
             // Job Outputs
             JobOutputs = new Dictionary<string, VariableValue>(StringComparer.OrdinalIgnoreCase);
 
@@ -587,12 +599,6 @@ namespace GitHub.Runner.Worker
             // File table
             FileTable = new List<String>(message.FileTable ?? new string[0]);
 
-            // Expression functions
-            if (Variables.GetBoolean("System.HashFilesV2") == true)
-            {
-                ExpressionConstants.UpdateFunction<Handlers.HashFiles>("hashFiles", 1, byte.MaxValue);
-            }
-
             // Expression values
             if (message.ContextData?.Count > 0)
             {
@@ -909,11 +915,19 @@ namespace GitHub.Runner.Worker
             }
         }
 
-        public static PipelineTemplateEvaluator ToPipelineTemplateEvaluator(this IExecutionContext context)
+        public static IEnumerable<KeyValuePair<string, object>> ToExpressionState(this IExecutionContext context)
         {
-            var templateTrace = context.ToTemplateTraceWriter();
-            var schema = new PipelineTemplateSchemaFactory().CreateSchema();
-            return new PipelineTemplateEvaluator(templateTrace, schema, context.FileTable);
+            return new[] { new KeyValuePair<string, object>(nameof(IExecutionContext), context) };
+        }
+
+        public static PipelineTemplateEvaluator ToPipelineTemplateEvaluator(this IExecutionContext context, ObjectTemplating.ITraceWriter traceWriter = null)
+        {
+            if (traceWriter == null)
+            {
+                traceWriter = context.ToTemplateTraceWriter();
+            }
+            var schema = PipelineTemplateSchemaFactory.GetSchema();
+            return new PipelineTemplateEvaluator(traceWriter, schema, context.FileTable);
         }
 
         public static ObjectTemplating.ITraceWriter ToTemplateTraceWriter(this IExecutionContext context)
@@ -928,6 +942,7 @@ namespace GitHub.Runner.Worker
 
         internal TemplateTraceWriter(IExecutionContext executionContext)
         {
+            ArgUtil.NotNull(executionContext, nameof(executionContext));
             _executionContext = executionContext;
         }
 

src/Runner.Worker/ExpressionManager.cs

@@ -1,162 +0,0 @@
-using System;
-using System.Collections;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using GitHub.DistributedTask.Expressions2;
-using GitHub.DistributedTask.Expressions2.Sdk;
-using GitHub.DistributedTask.WebApi;
-using GitHub.Runner.Common;
-using GitHub.Runner.Common.Util;
-using GitHub.Runner.Sdk;
-using ObjectTemplating = GitHub.DistributedTask.ObjectTemplating;
-using PipelineTemplateConstants = GitHub.DistributedTask.Pipelines.ObjectTemplating.PipelineTemplateConstants;
-
-namespace GitHub.Runner.Worker
-{
-    [ServiceLocator(Default = typeof(ExpressionManager))]
-    public interface IExpressionManager : IRunnerService
-    {
-        ConditionResult Evaluate(IExecutionContext context, string condition, bool hostTracingOnly = false);
-    }
-
-    public sealed class ExpressionManager : RunnerService, IExpressionManager
-    {
-        public ConditionResult Evaluate(IExecutionContext executionContext, string condition, bool hostTracingOnly = false)
-        {
-            ArgUtil.NotNull(executionContext, nameof(executionContext));
-
-            ConditionResult result = new ConditionResult();
-            var expressionTrace = new TraceWriter(Trace, hostTracingOnly ? null : executionContext);
-            var tree = Parse(executionContext, expressionTrace, condition);
-            var expressionResult = tree.Evaluate(expressionTrace, HostContext.SecretMasker, state: executionContext, options: null);
-            result.Value = expressionResult.IsTruthy;
-            result.Trace = expressionTrace.Trace;
-
-            return result;
-        }
-
-        private static IExpressionNode Parse(IExecutionContext executionContext, TraceWriter expressionTrace, string condition)
-        {
-            ArgUtil.NotNull(executionContext, nameof(executionContext));
-
-            if (string.IsNullOrWhiteSpace(condition))
-            {
-                condition = $"{PipelineTemplateConstants.Success}()";
-            }
-
-            var parser = new ExpressionParser();
-            var namedValues = executionContext.ExpressionValues.Keys.Select(x => new NamedValueInfo<ContextValueNode>(x)).ToArray();
-            var functions = new IFunctionInfo[]
-            {
-                new FunctionInfo<AlwaysNode>(name: Constants.Expressions.Always, minParameters: 0, maxParameters: 0),
-                new FunctionInfo<CancelledNode>(name: Constants.Expressions.Cancelled, minParameters: 0, maxParameters: 0),
-                new FunctionInfo<FailureNode>(name: Constants.Expressions.Failure, minParameters: 0, maxParameters: 0),
-                new FunctionInfo<SuccessNode>(name: Constants.Expressions.Success, minParameters: 0, maxParameters: 0),
-            };
-            return parser.CreateTree(condition, expressionTrace, namedValues, functions) ?? new SuccessNode();
-        }
-
-        private sealed class TraceWriter : DistributedTask.Expressions2.ITraceWriter
-        {
-            private readonly IExecutionContext _executionContext;
-            private readonly Tracing _trace;
-            private readonly StringBuilder _traceBuilder = new StringBuilder();
-
-            public string Trace => _traceBuilder.ToString();
-
-            public TraceWriter(Tracing trace, IExecutionContext executionContext)
-            {
-                ArgUtil.NotNull(trace, nameof(trace));
-                _trace = trace;
-                _executionContext = executionContext;
-            }
-
-            public void Info(string message)
-            {
-                _trace.Info(message);
-                _executionContext?.Debug(message);
-                _traceBuilder.AppendLine(message);
-            }
-
-            public void Verbose(string message)
-            {
-                _trace.Verbose(message);
-                _executionContext?.Debug(message);
-            }
-        }
-
-        private sealed class AlwaysNode : Function
-        {
-            protected override Object EvaluateCore(EvaluationContext context, out ResultMemory resultMemory)
-            {
-                resultMemory = null;
-                return true;
-            }
-        }
-
-        private sealed class CancelledNode : Function
-        {
-            protected sealed override object EvaluateCore(EvaluationContext evaluationContext, out ResultMemory resultMemory)
-            {
-                resultMemory = null;
-                var executionContext = evaluationContext.State as IExecutionContext;
-                ArgUtil.NotNull(executionContext, nameof(executionContext));
-                ActionResult jobStatus = executionContext.JobContext.Status ?? ActionResult.Success;
-                return jobStatus == ActionResult.Cancelled;
-            }
-        }
-
-        private sealed class FailureNode : Function
-        {
-            protected sealed override object EvaluateCore(EvaluationContext evaluationContext, out ResultMemory resultMemory)
-            {
-                resultMemory = null;
-                var executionContext = evaluationContext.State as IExecutionContext;
-                ArgUtil.NotNull(executionContext, nameof(executionContext));
-                ActionResult jobStatus = executionContext.JobContext.Status ?? ActionResult.Success;
-                return jobStatus == ActionResult.Failure;
-            }
-        }
-
-        private sealed class SuccessNode : Function
-        {
-            protected sealed override object EvaluateCore(EvaluationContext evaluationContext, out ResultMemory resultMemory)
-            {
-                resultMemory = null;
-                var executionContext = evaluationContext.State as IExecutionContext;
-                ArgUtil.NotNull(executionContext, nameof(executionContext));
-                ActionResult jobStatus = executionContext.JobContext.Status ?? ActionResult.Success;
-                return jobStatus == ActionResult.Success;
-            }
-        }
-
-        private sealed class ContextValueNode : NamedValue
-        {
-            protected override Object EvaluateCore(EvaluationContext evaluationContext, out ResultMemory resultMemory)
-            {
-                resultMemory = null;
-                var jobContext = evaluationContext.State as IExecutionContext;
-                ArgUtil.NotNull(jobContext, nameof(jobContext));
-                return jobContext.ExpressionValues[Name];
-            }
-        }
-    }
-
-    public class ConditionResult
-    {
-        public ConditionResult(bool value = false, string trace = null)
-        {
-            this.Value = value;
-            this.Trace = trace;
-        }
-
-        public bool Value { get; set; }
-        public string Trace { get; set; }
-
-        public static implicit operator ConditionResult(bool value)
-        {
-            return new ConditionResult(value);
-        }
-    }
-}

src/Runner.Worker/Expressions/AlwaysFunction.cs

@@ -0,0 +1,25 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.Expressions2.Sdk;
+using GitHub.DistributedTask.WebApi;
+using GitHub.Runner.Common;
+using GitHub.Runner.Common.Util;
+using GitHub.Runner.Sdk;
+using ObjectTemplating = GitHub.DistributedTask.ObjectTemplating;
+using PipelineTemplateConstants = GitHub.DistributedTask.Pipelines.ObjectTemplating.PipelineTemplateConstants;
+
+namespace GitHub.Runner.Worker.Expressions
+{
+    public sealed class AlwaysFunction : Function
+    {
+        protected override Object EvaluateCore(EvaluationContext context, out ResultMemory resultMemory)
+        {
+            resultMemory = null;
+            return true;
+        }
+    }
+}

src/Runner.Worker/Expressions/CancelledFunction.cs

@@ -0,0 +1,31 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.Expressions2.Sdk;
+using GitHub.DistributedTask.ObjectTemplating;
+using GitHub.DistributedTask.WebApi;
+using GitHub.Runner.Common;
+using GitHub.Runner.Common.Util;
+using GitHub.Runner.Sdk;
+using ObjectTemplating = GitHub.DistributedTask.ObjectTemplating;
+using PipelineTemplateConstants = GitHub.DistributedTask.Pipelines.ObjectTemplating.PipelineTemplateConstants;
+
+namespace GitHub.Runner.Worker.Expressions
+{
+    public sealed class CancelledFunction : Function
+    {
+        protected sealed override object EvaluateCore(EvaluationContext evaluationContext, out ResultMemory resultMemory)
+        {
+            resultMemory = null;
+            var templateContext = evaluationContext.State as TemplateContext;
+            ArgUtil.NotNull(templateContext, nameof(templateContext));
+            var executionContext = templateContext.State[nameof(IExecutionContext)] as IExecutionContext;
+            ArgUtil.NotNull(executionContext, nameof(executionContext));
+            ActionResult jobStatus = executionContext.JobContext.Status ?? ActionResult.Success;
+            return jobStatus == ActionResult.Cancelled;
+        }
+    }
+}

src/Runner.Worker/Expressions/FailureFunction.cs

@@ -0,0 +1,31 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.Expressions2.Sdk;
+using GitHub.DistributedTask.ObjectTemplating;
+using GitHub.DistributedTask.WebApi;
+using GitHub.Runner.Common;
+using GitHub.Runner.Common.Util;
+using GitHub.Runner.Sdk;
+using ObjectTemplating = GitHub.DistributedTask.ObjectTemplating;
+using PipelineTemplateConstants = GitHub.DistributedTask.Pipelines.ObjectTemplating.PipelineTemplateConstants;
+
+namespace GitHub.Runner.Worker.Expressions
+{
+    public sealed class FailureFunction : Function
+    {
+        protected sealed override object EvaluateCore(EvaluationContext evaluationContext, out ResultMemory resultMemory)
+        {
+            resultMemory = null;
+            var templateContext = evaluationContext.State as TemplateContext;
+            ArgUtil.NotNull(templateContext, nameof(templateContext));
+            var executionContext = templateContext.State[nameof(IExecutionContext)] as IExecutionContext;
+            ArgUtil.NotNull(executionContext, nameof(executionContext));
+            ActionResult jobStatus = executionContext.JobContext.Status ?? ActionResult.Success;
+            return jobStatus == ActionResult.Failure;
+        }
+    }
+}

src/Runner.Worker/Expressions/HashFilesFunction.cs

@@ -8,28 +8,9 @@ using System.Reflection;
 using System.Threading;
 using System.Collections.Generic;
 
-namespace GitHub.Runner.Worker.Handlers
+namespace GitHub.Runner.Worker.Expressions
 {
-    public class FunctionTrace : ITraceWriter
-    {
-        private GitHub.DistributedTask.Expressions2.ITraceWriter _trace;
-
-        public FunctionTrace(GitHub.DistributedTask.Expressions2.ITraceWriter trace)
-        {
-            _trace = trace;
-        }
-        public void Info(string message)
-        {
-            _trace.Info(message);
-        }
-
-        public void Verbose(string message)
-        {
-            _trace.Info(message);
-        }
-    }
-
-    public sealed class HashFiles : Function
+    public sealed class HashFilesFunction : Function
     {
         protected sealed override Object EvaluateCore(
             EvaluationContext context,
@@ -82,7 +63,7 @@ namespace GitHub.Runner.Worker.Handlers
             string node = Path.Combine(runnerRoot, "externals", "node12", "bin", $"node{IOUtil.ExeExtension}");
             string hashFilesScript = Path.Combine(binDir, "hashFiles");
             var hashResult = string.Empty;
-            var p = new ProcessInvoker(new FunctionTrace(context.Trace));
+            var p = new ProcessInvoker(new HashFilesTrace(context.Trace));
             p.ErrorDataReceived += ((_, data) =>
             {
                 if (!string.IsNullOrEmpty(data.Data) && data.Data.StartsWith("__OUTPUT__") && data.Data.EndsWith("__OUTPUT__"))
@@ -122,5 +103,24 @@ namespace GitHub.Runner.Worker.Handlers
 
             return hashResult;
         }
+
+        private sealed class HashFilesTrace : ITraceWriter
+        {
+            private GitHub.DistributedTask.Expressions2.ITraceWriter _trace;
+
+            public HashFilesTrace(GitHub.DistributedTask.Expressions2.ITraceWriter trace)
+            {
+                _trace = trace;
+            }
+            public void Info(string message)
+            {
+                _trace.Info(message);
+            }
+
+            public void Verbose(string message)
+            {
+                _trace.Info(message);
+            }
+        }
     }
 }

src/Runner.Worker/Expressions/SuccessFunction.cs

@@ -0,0 +1,31 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.Expressions2.Sdk;
+using GitHub.DistributedTask.ObjectTemplating;
+using GitHub.DistributedTask.WebApi;
+using GitHub.Runner.Common;
+using GitHub.Runner.Common.Util;
+using GitHub.Runner.Sdk;
+using ObjectTemplating = GitHub.DistributedTask.ObjectTemplating;
+using PipelineTemplateConstants = GitHub.DistributedTask.Pipelines.ObjectTemplating.PipelineTemplateConstants;
+
+namespace GitHub.Runner.Worker.Expressions
+{
+    public sealed class SuccessFunction : Function
+    {
+        protected sealed override object EvaluateCore(EvaluationContext evaluationContext, out ResultMemory resultMemory)
+        {
+            resultMemory = null;
+            var templateContext = evaluationContext.State as TemplateContext;
+            ArgUtil.NotNull(templateContext, nameof(templateContext));
+            var executionContext = templateContext.State[nameof(IExecutionContext)] as IExecutionContext;
+            ArgUtil.NotNull(executionContext, nameof(executionContext));
+            ActionResult jobStatus = executionContext.JobContext.Status ?? ActionResult.Success;
+            return jobStatus == ActionResult.Success;
+        }
+    }
+}

src/Runner.Worker/GitHubContext.cs

@@ -10,6 +10,7 @@ namespace GitHub.Runner.Worker
         {
             "action",
             "actor",
+            "api_url", // temp for GHES alpha release
             "base_ref",
             "event_name",
             "event_path",
@@ -17,9 +18,11 @@ namespace GitHub.Runner.Worker
             "job",
             "ref",
             "repository",
+            "repository_owner",
             "run_id",
             "run_number",
             "sha",
+            "url", // temp for GHES alpha release
             "workflow",
             "workspace",
         };

src/Runner.Worker/Handlers/ContainerActionHandler.cs

@@ -97,14 +97,14 @@ namespace GitHub.Runner.Worker.Handlers
                 }
             }
 
-            var evaluateContext = new Dictionary<string, PipelineContextData>(StringComparer.OrdinalIgnoreCase);
-            evaluateContext["inputs"] = inputsContext;
+            var extraExpressionValues = new Dictionary<string, PipelineContextData>(StringComparer.OrdinalIgnoreCase);
+            extraExpressionValues["inputs"] = inputsContext;
 
             var manifestManager = HostContext.GetService<IActionManifestManager>();
             if (Data.Arguments != null)
             {
                 container.ContainerEntryPointArgs = "";
-                var evaluatedArgs = manifestManager.EvaluateContainerArguments(ExecutionContext, Data.Arguments, evaluateContext);
+                var evaluatedArgs = manifestManager.EvaluateContainerArguments(ExecutionContext, Data.Arguments, extraExpressionValues);
                 foreach (var arg in evaluatedArgs)
                 {
                     if (!string.IsNullOrEmpty(arg))
@@ -124,7 +124,7 @@ namespace GitHub.Runner.Worker.Handlers
 
             if (Data.Environment != null)
             {
-                var evaluatedEnv = manifestManager.EvaluateContainerEnvironment(ExecutionContext, Data.Environment, evaluateContext);
+                var evaluatedEnv = manifestManager.EvaluateContainerEnvironment(ExecutionContext, Data.Environment, extraExpressionValues);
                 foreach (var env in evaluatedEnv)
                 {
                     if (!this.Environment.ContainsKey(env.Key))

src/Runner.Worker/Handlers/ScriptHandler.cs

@@ -58,12 +58,21 @@ namespace GitHub.Runner.Worker.Handlers
             string shellCommandPath = null;
             bool validateShellOnHost = !(StepHost is ContainerStepHost);
             string prependPath = string.Join(Path.PathSeparator.ToString(), ExecutionContext.PrependPath.Reverse<string>());
-            Inputs.TryGetValue("shell", out var shell);
+            string shell = null;
+            if (!Inputs.TryGetValue("shell", out shell) || string.IsNullOrEmpty(shell))
+            {
+                // TODO: figure out how defaults interact with template later
+                // for now, we won't check job.defaults if we are inside a template.
+                if (string.IsNullOrEmpty(ExecutionContext.ScopeName) && ExecutionContext.JobDefaults.TryGetValue("run", out var runDefaults))
+                {
+                    runDefaults.TryGetValue("shell", out shell);
+                }
+            }
             if (string.IsNullOrEmpty(shell))
             {
 #if OS_WINDOWS
                 shellCommand = "pwsh";
-                if(validateShellOnHost)
+                if (validateShellOnHost)
                 {
                     shellCommandPath = WhichUtil.Which(shellCommand, require: false, Trace, prependPath);
                     if (string.IsNullOrEmpty(shellCommandPath))
@@ -139,11 +148,36 @@ namespace GitHub.Runner.Worker.Handlers
             Inputs.TryGetValue("script", out var contents);
             contents = contents ?? string.Empty;
 
-            Inputs.TryGetValue("workingDirectory", out var workingDirectory);
+            string workingDirectory = null;
+            if (!Inputs.TryGetValue("workingDirectory", out workingDirectory))
+            {
+                // TODO: figure out how defaults interact with template later
+                // for now, we won't check job.defaults if we are inside a template.
+                if (string.IsNullOrEmpty(ExecutionContext.ScopeName) && ExecutionContext.JobDefaults.TryGetValue("run", out var runDefaults))
+                {
+                    if (runDefaults.TryGetValue("working-directory", out workingDirectory))
+                    {
+                        ExecutionContext.Debug("Overwrite 'working-directory' base on job defaults.");
+                    }
+                }
+            }
             var workspaceDir = githubContext["workspace"] as StringContextData;
             workingDirectory = Path.Combine(workspaceDir, workingDirectory ?? string.Empty);
 
-            Inputs.TryGetValue("shell", out var shell);
+            string shell = null;
+            if (!Inputs.TryGetValue("shell", out shell) || string.IsNullOrEmpty(shell))
+            {
+                // TODO: figure out how defaults interact with template later
+                // for now, we won't check job.defaults if we are inside a template.
+                if (string.IsNullOrEmpty(ExecutionContext.ScopeName) && ExecutionContext.JobDefaults.TryGetValue("run", out var runDefaults))
+                {
+                    if (runDefaults.TryGetValue("shell", out shell))
+                    {
+                        ExecutionContext.Debug("Overwrite 'shell' base on job defaults.");
+                    }
+                }
+            }
+
             var isContainerStepHost = StepHost is ContainerStepHost;
 
             string prependPath = string.Join(Path.PathSeparator.ToString(), ExecutionContext.PrependPath.Reverse<string>());

src/Runner.Worker/JobExtension.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
+using System.Globalization;
 using System.IO;
 using System.Linq;
 using System.Runtime.Serialization;
@@ -127,12 +128,23 @@ namespace GitHub.Runner.Worker
                     context.SetRunnerContext("workspace", Path.Combine(_workDirectory, trackingConfig.PipelineDirectory));
                     context.SetGitHubContext("workspace", Path.Combine(_workDirectory, trackingConfig.WorkspaceDirectory));
 
+                    // Temporary hack for GHES alpha
+                    var configurationStore = HostContext.GetService<IConfigurationStore>();
+                    var runnerSettings = configurationStore.GetSettings();
+                    if (!runnerSettings.IsHostedServer && !string.IsNullOrEmpty(runnerSettings.GitHubUrl))
+                    {
+                        var url = new Uri(runnerSettings.GitHubUrl);
+                        var portInfo = url.IsDefaultPort ? string.Empty : $":{url.Port.ToString(CultureInfo.InvariantCulture)}";
+                        context.SetGitHubContext("url", $"{url.Scheme}://{url.Host}{portInfo}");
+                        context.SetGitHubContext("api_url", $"{url.Scheme}://{url.Host}{portInfo}/api/v3");
+                    }
+
                     // Evaluate the job-level environment variables
                     context.Debug("Evaluating job-level environment variables");
                     var templateEvaluator = context.ToPipelineTemplateEvaluator();
                     foreach (var token in message.EnvironmentVariables)
                     {
-                        var environmentVariables = templateEvaluator.EvaluateStepEnvironment(token, jobContext.ExpressionValues, VarUtil.EnvironmentVariableKeyComparer);
+                        var environmentVariables = templateEvaluator.EvaluateStepEnvironment(token, jobContext.ExpressionValues, jobContext.ExpressionFunctions, VarUtil.EnvironmentVariableKeyComparer);
                         foreach (var pair in environmentVariables)
                         {
                             context.EnvironmentVariables[pair.Key] = pair.Value ?? string.Empty;
@@ -142,7 +154,7 @@ namespace GitHub.Runner.Worker
 
                     // Evaluate the job container
                     context.Debug("Evaluating job container");
-                    var container = templateEvaluator.EvaluateJobContainer(message.JobContainer, jobContext.ExpressionValues);
+                    var container = templateEvaluator.EvaluateJobContainer(message.JobContainer, jobContext.ExpressionValues, jobContext.ExpressionFunctions);
                     if (container != null)
                     {
                         jobContext.Container = new Container.ContainerInfo(HostContext, container);
@@ -150,7 +162,7 @@ namespace GitHub.Runner.Worker
 
                     // Evaluate the job service containers
                     context.Debug("Evaluating job service containers");
-                    var serviceContainers = templateEvaluator.EvaluateJobServiceContainers(message.JobServiceContainers, jobContext.ExpressionValues);
+                    var serviceContainers = templateEvaluator.EvaluateJobServiceContainers(message.JobServiceContainers, jobContext.ExpressionValues, jobContext.ExpressionFunctions);
                     if (serviceContainers?.Count > 0)
                     {
                         foreach (var pair in serviceContainers)
@@ -161,6 +173,26 @@ namespace GitHub.Runner.Worker
                         }
                     }
 
+                    // Evaluate the job defaults
+                    context.Debug("Evaluating job defaults");
+                    foreach (var token in message.Defaults)
+                    {
+                        var defaults = token.AssertMapping("defaults");
+                        if (defaults.Any(x => string.Equals(x.Key.AssertString("defaults key").Value, "run", StringComparison.OrdinalIgnoreCase)))
+                        {
+                            context.JobDefaults["run"] = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
+                            var defaultsRun = defaults.First(x => string.Equals(x.Key.AssertString("defaults key").Value, "run", StringComparison.OrdinalIgnoreCase));
+                            var jobDefaults = templateEvaluator.EvaluateJobDefaultsRun(defaultsRun.Value, jobContext.ExpressionValues, jobContext.ExpressionFunctions);
+                            foreach (var pair in jobDefaults)
+                            {
+                                if (!string.IsNullOrEmpty(pair.Value))
+                                {
+                                    context.JobDefaults["run"][pair.Key] = pair.Value;
+                                }
+                            }
+                        }
+                    }
+
                     // Build up 2 lists of steps, pre-job, job
                     // Download actions not already in the cache
                     Trace.Info("Downloading actions");
@@ -317,7 +349,7 @@ namespace GitHub.Runner.Worker
                             context.ExpressionValues["steps"] = context.StepsContext.GetScope(context.ScopeName);
 
                             var templateEvaluator = context.ToPipelineTemplateEvaluator();
-                            var outputs = templateEvaluator.EvaluateJobOutput(message.JobOutputs, context.ExpressionValues);
+                            var outputs = templateEvaluator.EvaluateJobOutput(message.JobOutputs, context.ExpressionValues, context.ExpressionFunctions);
                             foreach (var output in outputs)
                             {
                                 if (string.IsNullOrEmpty(output.Value))

src/Runner.Worker/StepsRunner.cs

@@ -1,8 +1,6 @@
-using GitHub.DistributedTask.WebApi;
-using Pipelines = GitHub.DistributedTask.Pipelines;
-using GitHub.Runner.Common.Util;
 using System;
 using System.Collections.Generic;
+using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 using GitHub.DistributedTask.Expressions2;
@@ -10,8 +8,13 @@ using GitHub.DistributedTask.ObjectTemplating.Tokens;
 using GitHub.DistributedTask.Pipelines;
 using GitHub.DistributedTask.Pipelines.ContextData;
 using GitHub.DistributedTask.Pipelines.ObjectTemplating;
+using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Common;
+using GitHub.Runner.Common.Util;
 using GitHub.Runner.Sdk;
+using GitHub.Runner.Worker.Expressions;
+using ObjectTemplating = GitHub.DistributedTask.ObjectTemplating;
+using Pipelines = GitHub.DistributedTask.Pipelines;
 
 namespace GitHub.Runner.Worker
 {
@@ -63,11 +66,7 @@ namespace GitHub.Runner.Worker
                 }
 
                 var step = jobContext.JobSteps.Dequeue();
-                IStep nextStep = null;
-                if (jobContext.JobSteps.Count > 0)
-                {
-                    nextStep = jobContext.JobSteps.Peek();
-                }
+                var nextStep = jobContext.JobSteps.Count > 0 ? jobContext.JobSteps.Peek() : null;
 
                 Trace.Info($"Processing step: DisplayName='{step.DisplayName}'");
                 ArgUtil.NotNull(step.ExecutionContext, nameof(step.ExecutionContext));
@@ -76,6 +75,13 @@ namespace GitHub.Runner.Worker
                 // Start
                 step.ExecutionContext.Start();
 
+                // Expression functions
+                step.ExecutionContext.ExpressionFunctions.Add(new FunctionInfo<AlwaysFunction>(PipelineTemplateConstants.Always, 0, 0));
+                step.ExecutionContext.ExpressionFunctions.Add(new FunctionInfo<CancelledFunction>(PipelineTemplateConstants.Cancelled, 0, 0));
+                step.ExecutionContext.ExpressionFunctions.Add(new FunctionInfo<FailureFunction>(PipelineTemplateConstants.Failure, 0, 0));
+                step.ExecutionContext.ExpressionFunctions.Add(new FunctionInfo<SuccessFunction>(PipelineTemplateConstants.Success, 0, 0));
+                step.ExecutionContext.ExpressionFunctions.Add(new FunctionInfo<HashFilesFunction>(PipelineTemplateConstants.HashFiles, 1, byte.MaxValue));
+
                 // Initialize scope
                 if (InitializeScope(step, scopeInputs))
                 {
@@ -99,14 +105,13 @@ namespace GitHub.Runner.Worker
 
                         // Evaluate and merge action's env block to env context
                         var templateEvaluator = step.ExecutionContext.ToPipelineTemplateEvaluator();
-                        var actionEnvironment = templateEvaluator.EvaluateStepEnvironment(actionStep.Action.Environment, step.ExecutionContext.ExpressionValues, VarUtil.EnvironmentVariableKeyComparer);
+                        var actionEnvironment = templateEvaluator.EvaluateStepEnvironment(actionStep.Action.Environment, step.ExecutionContext.ExpressionValues, step.ExecutionContext.ExpressionFunctions, VarUtil.EnvironmentVariableKeyComparer);
                         foreach (var env in actionEnvironment)
                         {
                             envContext[env.Key] = new StringContextData(env.Value ?? string.Empty);
                         }
                     }
 
-                    var expressionManager = HostContext.GetService<IExpressionManager>();
                     try
                     {
                         // Register job cancellation call back only if job cancellation token not been fire before each step run
@@ -120,28 +125,29 @@ namespace GitHub.Runner.Worker
                                 jobContext.JobContext.Status = jobContext.Result?.ToActionResult();
 
                                 step.ExecutionContext.Debug($"Re-evaluate condition on job cancellation for step: '{step.DisplayName}'.");
-                                ConditionResult conditionReTestResult;
+                                var conditionReTestTraceWriter = new ConditionTraceWriter(Trace, null); // host tracing only
+                                var conditionReTestResult = false;
                                 if (HostContext.RunnerShutdownToken.IsCancellationRequested)
                                 {
                                     step.ExecutionContext.Debug($"Skip Re-evaluate condition on runner shutdown.");
-                                    conditionReTestResult = false;
                                 }
                                 else
                                 {
                                     try
                                     {
-                                        conditionReTestResult = expressionManager.Evaluate(step.ExecutionContext, step.Condition, hostTracingOnly: true);
+                                        var templateEvaluator = step.ExecutionContext.ToPipelineTemplateEvaluator(conditionReTestTraceWriter);
+                                        var condition = new BasicExpressionToken(null, null, null, step.Condition);
+                                        conditionReTestResult = templateEvaluator.EvaluateStepIf(condition, step.ExecutionContext.ExpressionValues, step.ExecutionContext.ExpressionFunctions, step.ExecutionContext.ToExpressionState());
                                     }
                                     catch (Exception ex)
                                     {
                                         // Cancel the step since we get exception while re-evaluate step condition.
                                         Trace.Info("Caught exception from expression when re-test condition on job cancellation.");
                                         step.ExecutionContext.Error(ex);
-                                        conditionReTestResult = false;
                                     }
                                 }
 
-                                if (!conditionReTestResult.Value)
+                                if (!conditionReTestResult)
                                 {
                                     // Cancel the step.
                                     Trace.Info("Cancel current running step.");
@@ -161,34 +167,35 @@ namespace GitHub.Runner.Worker
 
                         // Evaluate condition.
                         step.ExecutionContext.Debug($"Evaluating condition for step: '{step.DisplayName}'");
-                        Exception conditionEvaluateError = null;
-                        ConditionResult conditionResult;
+                        var conditionTraceWriter = new ConditionTraceWriter(Trace, step.ExecutionContext);
+                        var conditionResult = false;
+                        var conditionEvaluateError = default(Exception);
                         if (HostContext.RunnerShutdownToken.IsCancellationRequested)
                         {
                             step.ExecutionContext.Debug($"Skip evaluate condition on runner shutdown.");
-                            conditionResult = false;
                         }
                         else
                         {
                             try
                             {
-                                conditionResult = expressionManager.Evaluate(step.ExecutionContext, step.Condition);
+                                var templateEvaluator = step.ExecutionContext.ToPipelineTemplateEvaluator(conditionTraceWriter);
+                                var condition = new BasicExpressionToken(null, null, null, step.Condition);
+                                conditionResult = templateEvaluator.EvaluateStepIf(condition, step.ExecutionContext.ExpressionValues, step.ExecutionContext.ExpressionFunctions, step.ExecutionContext.ToExpressionState());
                             }
                             catch (Exception ex)
                             {
                                 Trace.Info("Caught exception from expression.");
                                 Trace.Error(ex);
-                                conditionResult = false;
                                 conditionEvaluateError = ex;
                             }
                         }
 
                         // no evaluate error but condition is false
-                        if (!conditionResult.Value && conditionEvaluateError == null)
+                        if (!conditionResult && conditionEvaluateError == null)
                         {
                             // Condition == false
                             Trace.Info("Skipping step due to condition evaluation.");
-                            CompleteStep(step, nextStep, TaskResult.Skipped, resultCode: conditionResult.Trace);
+                            CompleteStep(step, nextStep, TaskResult.Skipped, resultCode: conditionTraceWriter.Trace);
                         }
                         else if (conditionEvaluateError != null)
                         {
@@ -248,7 +255,7 @@ namespace GitHub.Runner.Worker
             var templateEvaluator = step.ExecutionContext.ToPipelineTemplateEvaluator();
             try
             {
-                timeoutMinutes = templateEvaluator.EvaluateStepTimeout(step.Timeout, step.ExecutionContext.ExpressionValues);
+                timeoutMinutes = templateEvaluator.EvaluateStepTimeout(step.Timeout, step.ExecutionContext.ExpressionValues, step.ExecutionContext.ExpressionFunctions);
             }
             catch (Exception ex)
             {
@@ -339,7 +346,7 @@ namespace GitHub.Runner.Worker
                 var continueOnError = false;
                 try
                 {
-                    continueOnError = templateEvaluator.EvaluateStepContinueOnError(step.ContinueOnError, step.ExecutionContext.ExpressionValues);
+                    continueOnError = templateEvaluator.EvaluateStepContinueOnError(step.ContinueOnError, step.ExecutionContext.ExpressionValues, step.ExecutionContext.ExpressionFunctions);
                 }
                 catch (Exception ex)
                 {
@@ -392,7 +399,7 @@ namespace GitHub.Runner.Worker
                     var inputs = default(DictionaryContextData);
                     try
                     {
-                        inputs = templateEvaluator.EvaluateStepScopeInputs(scope.Inputs, executionContext.ExpressionValues);
+                        inputs = templateEvaluator.EvaluateStepScopeInputs(scope.Inputs, executionContext.ExpressionValues, executionContext.ExpressionFunctions);
                     }
                     catch (Exception ex)
                     {
@@ -448,7 +455,7 @@ namespace GitHub.Runner.Worker
                     var outputs = default(DictionaryContextData);
                     try
                     {
-                        outputs = templateEvaluator.EvaluateStepScopeOutputs(scope.Outputs, executionContext.ExpressionValues);
+                        outputs = templateEvaluator.EvaluateStepScopeOutputs(scope.Outputs, executionContext.ExpressionValues, executionContext.ExpressionFunctions);
                     }
                     catch (Exception ex)
                     {
@@ -476,5 +483,43 @@ namespace GitHub.Runner.Worker
 
             executionContext.Complete(result, resultCode: resultCode);
         }
+
+        private sealed class ConditionTraceWriter : ObjectTemplating::ITraceWriter
+        {
+            private readonly IExecutionContext _executionContext;
+            private readonly Tracing _trace;
+            private readonly StringBuilder _traceBuilder = new StringBuilder();
+
+            public string Trace => _traceBuilder.ToString();
+
+            public ConditionTraceWriter(Tracing trace, IExecutionContext executionContext)
+            {
+                ArgUtil.NotNull(trace, nameof(trace));
+                _trace = trace;
+                _executionContext = executionContext;
+            }
+
+            public void Error(string format, params Object[] args)
+            {
+                var message = StringUtil.Format(format, args);
+                _trace.Error(message);
+                _executionContext?.Debug(message);
+            }
+
+            public void Info(string format, params Object[] args)
+            {
+                var message = StringUtil.Format(format, args);
+                _trace.Info(message);
+                _executionContext?.Debug(message);
+                _traceBuilder.AppendLine(message);
+            }
+
+            public void Verbose(string format, params Object[] args)
+            {
+                var message = StringUtil.Format(format, args);
+                _trace.Verbose(message);
+                _executionContext?.Debug(message);
+            }
+        }
     }
 }

src/Runner.Worker/action_yaml.json

@@ -91,7 +91,8 @@
                 "strategy",
                 "matrix",
                 "job",
-                "runner"
+                "runner",
+                "hashFiles(1,255)"
             ],
             "string": {}
         },

src/Sdk/DTExpressions2/Expressions2/ExpressionConstants.cs

@@ -5,7 +5,7 @@ using GitHub.DistributedTask.Expressions2.Sdk.Functions;
 
 namespace GitHub.DistributedTask.Expressions2
 {
-    public static class ExpressionConstants
+    internal static class ExpressionConstants
     {
         static ExpressionConstants()
         {
@@ -16,7 +16,6 @@ namespace GitHub.DistributedTask.Expressions2
             AddFunction<StartsWith>("startsWith", 2, 2);
             AddFunction<ToJson>("toJson", 1, 1);
             AddFunction<FromJson>("fromJson", 1, 1);
-            AddFunction<HashFiles>("hashFiles", 1, 1);
         }
 
         private static void AddFunction<T>(String name, Int32 minParameters, Int32 maxParameters)
@@ -25,12 +24,6 @@ namespace GitHub.DistributedTask.Expressions2
             WellKnownFunctions.Add(name, new FunctionInfo<T>(name, minParameters, maxParameters));
         }
 
-        public static void UpdateFunction<T>(String name, Int32 minParameters, Int32 maxParameters)
-                    where T : Function, new()
-        {
-            WellKnownFunctions[name] = new FunctionInfo<T>(name, minParameters, maxParameters);
-        }
-
         internal static readonly String False = "false";
         internal static readonly String Infinity = "Infinity";
         internal static readonly Int32 MaxDepth = 50;

src/Sdk/DTExpressions2/Expressions2/Sdk/Functions/HashFiles.cs

@@ -1,122 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using Minimatch;
-using System.IO;
-using System.Security.Cryptography;
-using GitHub.DistributedTask.Expressions2.Sdk;
-using GitHub.DistributedTask.Pipelines.ContextData;
-using GitHub.DistributedTask.Pipelines.ObjectTemplating;
-namespace GitHub.DistributedTask.Expressions2.Sdk.Functions
-{
-    internal sealed class HashFiles : Function
-    {
-        protected sealed override Object EvaluateCore(
-            EvaluationContext context,
-            out ResultMemory resultMemory)
-        {
-            resultMemory = null;
-
-            // hashFiles() only works on the runner and only works with files under GITHUB_WORKSPACE
-            // Since GITHUB_WORKSPACE is set by runner, I am using that as the fact of this code runs on server or runner.
-            if (context.State is ObjectTemplating.TemplateContext templateContext &&
-                templateContext.ExpressionValues.TryGetValue(PipelineTemplateConstants.GitHub, out var githubContextData) &&
-                githubContextData is DictionaryContextData githubContext &&
-                githubContext.TryGetValue(PipelineTemplateConstants.Workspace, out var workspace) == true &&
-                workspace is StringContextData workspaceData)
-            {
-                string searchRoot = workspaceData.Value;
-                string pattern = Parameters[0].Evaluate(context).ConvertToString();
-
-                // Convert slashes on Windows
-                if (s_isWindows)
-                {
-                    pattern = pattern.Replace('\\', '/');
-                }
-
-                // Root the pattern
-                if (!Path.IsPathRooted(pattern))
-                {
-                    var patternRoot = s_isWindows ? searchRoot.Replace('\\', '/').TrimEnd('/') : searchRoot.TrimEnd('/');
-                    pattern = string.Concat(patternRoot, "/", pattern);
-                }
-
-                // Get all files
-                context.Trace.Info($"Search root directory: '{searchRoot}'");
-                context.Trace.Info($"Search pattern: '{pattern}'");
-                var files = Directory.GetFiles(searchRoot, "*", SearchOption.AllDirectories)
-                    .Select(x => s_isWindows ? x.Replace('\\', '/') : x)
-                    .OrderBy(x => x, StringComparer.Ordinal)
-                    .ToList();
-                if (files.Count == 0)
-                {
-                    throw new ArgumentException($"hashFiles('{ExpressionUtility.StringEscape(pattern)}') failed. Directory '{searchRoot}' is empty");
-                }
-                else
-                {
-                    context.Trace.Info($"Found {files.Count} files");
-                }
-
-                // Match
-                var matcher = new Minimatcher(pattern, s_minimatchOptions);
-                files = matcher.Filter(files)
-                    .Select(x => s_isWindows ? x.Replace('/', '\\') : x)
-                    .ToList();
-                if (files.Count == 0)
-                {
-                    throw new ArgumentException($"hashFiles('{ExpressionUtility.StringEscape(pattern)}') failed. Search pattern '{pattern}' doesn't match any file under '{searchRoot}'");
-                }
-                else
-                {
-                    context.Trace.Info($"{files.Count} matches to hash");
-                }
-
-                // Hash each file
-                List<byte> filesSha256 = new List<byte>();
-                foreach (var file in files)
-                {
-                    context.Trace.Info($"Hash {file}");
-                    using (SHA256 sha256hash = SHA256.Create())
-                    {
-                        using (var fileStream = File.OpenRead(file))
-                        {
-                            filesSha256.AddRange(sha256hash.ComputeHash(fileStream));
-                        }
-                    }
-                }
-
-                // Hash the hashes
-                using (SHA256 sha256hash = SHA256.Create())
-                {
-                    var hashBytes = sha256hash.ComputeHash(filesSha256.ToArray());
-                    StringBuilder hashString = new StringBuilder();
-                    for (int i = 0; i < hashBytes.Length; i++)
-                    {
-                        hashString.Append(hashBytes[i].ToString("x2"));
-                    }
-                    var result = hashString.ToString();
-                    context.Trace.Info($"Final hash result: '{result}'");
-                    return result;
-                }
-            }
-            else
-            {
-                throw new InvalidOperationException("'hashfiles' expression function is only supported under runner context.");
-            }
-        }
-
-        private static readonly bool s_isWindows = Environment.OSVersion.Platform != PlatformID.Unix && Environment.OSVersion.Platform != PlatformID.MacOSX;
-
-        // Only support basic globbing (* ? and []) and globstar (**)
-        private static readonly Options s_minimatchOptions = new Options
-        {
-            Dot = true,
-            NoBrace = true,
-            NoCase = s_isWindows,
-            NoComment = true,
-            NoExt = true,
-            NoNegate = true,
-        };
-    }
-}

src/Sdk/DTObjectTemplating/ObjectTemplating/Schema/Definition.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Linq;
 using GitHub.DistributedTask.ObjectTemplating.Tokens;
 
@@ -22,10 +23,27 @@ namespace GitHub.DistributedTask.ObjectTemplating.Schema
                 {
                     var context = definition[i].Value.AssertSequence($"{TemplateConstants.Context}");
                     definition.RemoveAt(i);
-                    Context = context
-                        .Select(x => x.AssertString($"{TemplateConstants.Context} item").Value)
-                        .Distinct()
-                        .ToArray();
+                    var readerContext = new HashSet<String>(StringComparer.OrdinalIgnoreCase);
+                    var evaluatorContext = new HashSet<String>(StringComparer.OrdinalIgnoreCase);
+                    foreach (TemplateToken item in context)
+                    {
+                        var itemStr = item.AssertString($"{TemplateConstants.Context} item").Value;
+                        readerContext.Add(itemStr);
+
+                        // Remove min/max parameter info
+                        var paramIndex = itemStr.IndexOf('(');
+                        if (paramIndex > 0)
+                        {
+                            evaluatorContext.Add(String.Concat(itemStr.Substring(0, paramIndex + 1), ")"));
+                        }
+                        else
+                        {
+                            evaluatorContext.Add(itemStr);
+                        }
+                    }
+
+                    ReaderContext = readerContext.ToArray();
+                    EvaluatorContext = evaluatorContext.ToArray();
                 }
                 else if (String.Equals(definitionKey.Value, TemplateConstants.Description, StringComparison.Ordinal))
                 {
@@ -40,7 +58,17 @@ namespace GitHub.DistributedTask.ObjectTemplating.Schema
 
         internal abstract DefinitionType DefinitionType { get; }
 
-        internal String[] Context { get; private set; } = new String[0];
+        /// <summary>
+        /// Used by the template reader to determine allowed expression values and functions.
+        /// Also used by the template reader to validate function min/max parameters.
+        /// </summary>
+        internal String[] ReaderContext { get; private set; } = new String[0];
+
+        /// <summary>
+        /// Used by the template evaluator to determine allowed expression values and functions.
+        /// The min/max parameter info is omitted.
+        /// </summary>
+        internal String[] EvaluatorContext { get; private set; } = new String[0];
 
         internal abstract void Validate(
             TemplateSchema schema,

src/Sdk/DTObjectTemplating/ObjectTemplating/Schema/MappingDefinition.cs

@@ -108,7 +108,7 @@ namespace GitHub.DistributedTask.ObjectTemplating.Schema
             {
                 var inherited = schema.GetDefinition(Inherits);
 
-                if (inherited.Context.Length > 0)
+                if (inherited.ReaderContext.Length > 0)
                 {
                     throw new NotSupportedException($"Property '{TemplateConstants.Context}' is not supported on inhertied definitions");
                 }

src/Sdk/DTObjectTemplating/ObjectTemplating/Schema/OneOfDefinition.cs

@@ -62,7 +62,7 @@ namespace GitHub.DistributedTask.ObjectTemplating.Schema
             {
                 var nestedDefinition = schema.GetDefinition(nestedType);
 
-                if (nestedDefinition.Context.Length > 0)
+                if (nestedDefinition.ReaderContext.Length > 0)
                 {
                     throw new ArgumentException($"'{name}' is a one-of definition and references another definition that defines context. This is currently not supported.");
                 }

src/Sdk/DTObjectTemplating/ObjectTemplating/TemplateEvaluator.cs

@@ -47,7 +47,16 @@ namespace GitHub.DistributedTask.ObjectTemplating
             var evaluator = new TemplateEvaluator(context, template, removeBytes);
             try
             {
-                var availableContext = new HashSet<String>(context.ExpressionValues.Keys.Concat(context.ExpressionFunctions.Select(x => $"{x.Name}({x.MinParameters},{x.MaxParameters})")));
+                var availableContext = new HashSet<String>(StringComparer.OrdinalIgnoreCase);
+                foreach (var key in context.ExpressionValues.Keys)
+                {
+                    availableContext.Add(key);
+                }
+                foreach (var function in context.ExpressionFunctions)
+                {
+                    availableContext.Add($"{function.Name}()");
+                }
+
                 var definitionInfo = new DefinitionInfo(context.Schema, type, availableContext);
                 result = evaluator.Evaluate(definitionInfo);
 
@@ -393,14 +402,13 @@ namespace GitHub.DistributedTask.ObjectTemplating
                 Definition = m_schema.GetDefinition(name);
 
                 // Determine whether to expand
-                if (Definition.Context.Length > 0)
+                m_allowedContext = Definition.EvaluatorContext;
+                if (Definition.EvaluatorContext.Length > 0)
                 {
-                    m_allowedContext = Definition.Context;
                     Expand = m_availableContext.IsSupersetOf(m_allowedContext);
                 }
                 else
                 {
-                    m_allowedContext = new String[0];
                     Expand = false;
                 }
             }
@@ -416,9 +424,9 @@ namespace GitHub.DistributedTask.ObjectTemplating
                 Definition = m_schema.GetDefinition(name);
 
                 // Determine whether to expand
-                if (Definition.Context.Length > 0)
+                if (Definition.EvaluatorContext.Length > 0)
                 {
-                    m_allowedContext = new HashSet<String>(parent.m_allowedContext.Concat(Definition.Context)).ToArray();
+                    m_allowedContext = new HashSet<String>(parent.m_allowedContext.Concat(Definition.EvaluatorContext), StringComparer.OrdinalIgnoreCase).ToArray();
                     Expand = m_availableContext.IsSupersetOf(m_allowedContext);
                 }
                 else

src/Sdk/DTObjectTemplating/ObjectTemplating/TemplateException.cs

@@ -49,6 +49,14 @@ namespace GitHub.DistributedTask.ObjectTemplating
             m_errors = new List<TemplateValidationError>(errors ?? Enumerable.Empty<TemplateValidationError>());
         }
 
+        public TemplateValidationException(
+            String message,
+            IEnumerable<TemplateValidationError> errors)
+            : this(message)
+        {
+            m_errors = new List<TemplateValidationError>(errors ?? Enumerable.Empty<TemplateValidationError>());
+        }
+
         public TemplateValidationException(String message)
             : base(message)
         {

src/Sdk/DTObjectTemplating/ObjectTemplating/TemplateReader.cs

@@ -780,15 +780,8 @@ namespace GitHub.DistributedTask.ObjectTemplating
                 // Lookup the definition
                 Definition = m_schema.GetDefinition(name);
 
-                // Determine whether to expand
-                if (Definition.Context.Length > 0)
-                {
-                    AllowedContext = Definition.Context;
-                }
-                else
-                {
-                    AllowedContext = new String[0];
-                }
+                // Record allowed context
+                AllowedContext = Definition.ReaderContext;
             }
 
             public DefinitionInfo(
@@ -800,10 +793,10 @@ namespace GitHub.DistributedTask.ObjectTemplating
                 // Lookup the definition
                 Definition = m_schema.GetDefinition(name);
 
-                // Determine whether to expand
-                if (Definition.Context.Length > 0)
+                // Record allowed context
+                if (Definition.ReaderContext.Length > 0)
                 {
-                    AllowedContext = new HashSet<String>(parent.AllowedContext.Concat(Definition.Context)).ToArray();
+                    AllowedContext = new HashSet<String>(parent.AllowedContext.Concat(Definition.ReaderContext), StringComparer.OrdinalIgnoreCase).ToArray();
                 }
                 else
                 {

src/Sdk/DTObjectTemplating/ObjectTemplating/TemplateValidationErrors.cs

@@ -2,6 +2,7 @@
 using System.Collections;
 using System.Collections.Generic;
 using System.ComponentModel;
+using System.Linq;
 using System.Runtime.Serialization;
 
 namespace GitHub.DistributedTask.ObjectTemplating
@@ -41,7 +42,7 @@ namespace GitHub.DistributedTask.ObjectTemplating
         {
             for (int i = 0; i < 50; i++)
             {
-                String message = !String.IsNullOrEmpty(messagePrefix) ? $"{messagePrefix} {ex.Message}" : ex.Message;
+                String message = !String.IsNullOrEmpty(messagePrefix) ? $"{messagePrefix} {ex.Message}" : ex.ToString();
                 Add(new TemplateValidationError(message));
                 if (ex.InnerException == null)
                 {
@@ -88,6 +89,23 @@ namespace GitHub.DistributedTask.ObjectTemplating
             }
         }
 
+        /// <summary>
+        /// Throws <c ref="TemplateValidationException" /> if any errors.
+        /// <param name="prefix">The error message prefix</param>
+        /// </summary>
+        public void Check(String prefix)
+        {
+            if (String.IsNullOrEmpty(prefix))
+            {
+                this.Check();
+            }
+            else if (m_errors.Count > 0)
+            {
+                var message = $"{prefix.Trim()} {String.Join(",", m_errors.Select(e => e.Message))}";
+                throw new TemplateValidationException(message, m_errors);
+            }
+        }
+
         public void Clear()
         {
             m_errors.Clear();

src/Sdk/DTObjectTemplating/ObjectTemplating/Tokens/ExpressionToken.cs

@@ -1,7 +1,9 @@
 using System;
+using System.Collections.Generic;
 using System.ComponentModel;
-using System.Linq;
+using System.Globalization;
 using System.Runtime.Serialization;
+using System.Text.RegularExpressions;
 using GitHub.DistributedTask.Expressions2;
 using GitHub.DistributedTask.Expressions2.Sdk;
 using GitHub.Services.WebApi.Internal;
@@ -35,11 +37,29 @@ namespace GitHub.DistributedTask.ObjectTemplating.Tokens
             String[] allowedContext,
             out Exception ex)
         {
-            // Create dummy allowed contexts
-            INamedValueInfo[] namedValues = null;
+            // Create dummy named values and functions
+            var namedValues = new List<INamedValueInfo>();
+            var functions = new List<IFunctionInfo>();
             if (allowedContext?.Length > 0)
             {
-                namedValues = allowedContext.Select(x => new NamedValueInfo<ContextValueNode>(x)).ToArray();
+                foreach (var contextItem in allowedContext)
+                {
+                    var match = s_function.Match(contextItem);
+                    if (match.Success)
+                    {
+                        var functionName = match.Groups[1].Value;
+                        var minParameters = Int32.Parse(match.Groups[2].Value, NumberStyles.None, CultureInfo.InvariantCulture);
+                        var maxParametersRaw = match.Groups[3].Value;
+                        var maxParameters = String.Equals(maxParametersRaw, TemplateConstants.MaxConstant, StringComparison.Ordinal)
+                            ? Int32.MaxValue
+                            : Int32.Parse(maxParametersRaw, NumberStyles.None, CultureInfo.InvariantCulture);
+                        functions.Add(new FunctionInfo<DummyFunction>(functionName, minParameters, maxParameters));
+                    }
+                    else
+                    {
+                        namedValues.Add(new NamedValueInfo<ContextValueNode>(contextItem));
+                    }
+                }
             }
 
             // Parse
@@ -47,7 +67,7 @@ namespace GitHub.DistributedTask.ObjectTemplating.Tokens
             ExpressionNode root = null;
             try
             {
-                root = new ExpressionParser().CreateTree(expression, null, namedValues, null) as ExpressionNode;
+                root = new ExpressionParser().CreateTree(expression, null, namedValues, functions) as ExpressionNode;
 
                 result = true;
                 ex = null;
@@ -60,5 +80,18 @@ namespace GitHub.DistributedTask.ObjectTemplating.Tokens
 
             return result;
         }
+
+        private sealed class DummyFunction : Function
+        {
+            protected override Object EvaluateCore(
+                EvaluationContext context,
+                out ResultMemory resultMemory)
+            {
+                resultMemory = null;
+                return null;
+            }
+        }
+
+        private static readonly Regex s_function = new Regex(@"^([a-zA-Z0-9_]+)\(([0-9]+),([0-9]+|MAX)\)$", RegexOptions.Compiled);
     }
 }

src/Sdk/DTObjectTemplating/ObjectTemplating/Tokens/TemplateTokenExtensions.cs

@@ -1,5 +1,8 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
+using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.Expressions2.Sdk;
 
 namespace GitHub.DistributedTask.ObjectTemplating.Tokens
 {
@@ -106,6 +109,43 @@ namespace GitHub.DistributedTask.ObjectTemplating.Tokens
             throw new ArgumentException($"Error while reading '{objectDescription}'. Unexpected value '{literal.ToString()}'");
         }
 
+        /// <summary>
+        /// Traverses the token and checks whether all required expression values
+        /// and functions are provided.
+        /// </summary>
+        public static bool CheckHasRequiredContext(
+            this TemplateToken token,
+            IReadOnlyObject expressionValues,
+            IList<IFunctionInfo> expressionFunctions)
+        {
+            var expressionTokens = token.Traverse()
+                .OfType<BasicExpressionToken>()
+                .ToArray();
+            var parser = new ExpressionParser();
+            foreach (var expressionToken in expressionTokens)
+            {
+                var tree = parser.ValidateSyntax(expressionToken.Expression, null);
+                foreach (var node in tree.Traverse())
+                {
+                    if (node is NamedValue namedValue)
+                    {
+                        if (expressionValues?.Keys.Any(x => string.Equals(x, namedValue.Name, StringComparison.OrdinalIgnoreCase)) != true)
+                        {
+                            return false;
+                        }
+                    }
+                    else if (node is Function function &&
+                        !ExpressionConstants.WellKnownFunctions.ContainsKey(function.Name) &&
+                        expressionFunctions?.Any(x => string.Equals(x.Name, function.Name, StringComparison.OrdinalIgnoreCase)) != true)
+                    {
+                        return false;
+                    }
+                }
+            }
+
+            return true;
+        }
+
         /// <summary>
         /// Returns all tokens (depth first)
         /// </summary>

src/Sdk/DTPipelines/Pipelines/AgentJobRequestMessage.cs

@@ -41,7 +41,8 @@ namespace GitHub.DistributedTask.Pipelines
             IEnumerable<JobStep> steps,
             IEnumerable<ContextScope> scopes,
             IList<String> fileTable,
-            TemplateToken jobOutputs)
+            TemplateToken jobOutputs,
+            IList<TemplateToken> defaults)
         {
             this.MessageType = JobRequestMessageTypes.PipelineAgentJobRequest;
             this.Plan = plan;
@@ -69,6 +70,11 @@ namespace GitHub.DistributedTask.Pipelines
                 m_environmentVariables = new List<TemplateToken>(environmentVariables);
             }
 
+            if (defaults?.Count > 0)
+            {
+                m_defaults = new List<TemplateToken>(defaults);
+            }
+
             this.ContextData = new Dictionary<String, PipelineContextData>(StringComparer.OrdinalIgnoreCase);
             if (contextData?.Count > 0)
             {
@@ -213,6 +219,21 @@ namespace GitHub.DistributedTask.Pipelines
             }
         }
 
+        /// <summary>
+        /// Gets the hierarchy of defaults to overlay, last wins.
+        /// </summary>
+        public IList<TemplateToken> Defaults
+        {
+            get
+            {
+                if (m_defaults == null)
+                {
+                    m_defaults = new List<TemplateToken>();
+                }
+                return m_defaults;
+            }
+        }
+
         /// <summary>
         /// Gets the collection of variables associated with the current context.
         /// </summary>
@@ -252,6 +273,9 @@ namespace GitHub.DistributedTask.Pipelines
             }
         }
 
+        /// <summary>
+        /// Gets the table of files used when parsing the pipeline (e.g. yaml files)
+        /// </summary>
         public IList<String> FileTable
         {
             get
@@ -372,6 +396,11 @@ namespace GitHub.DistributedTask.Pipelines
                 m_environmentVariables = null;
             }
 
+            if (m_defaults?.Count == 0)
+            {
+                m_defaults = null;
+            }
+
             if (m_fileTable?.Count == 0)
             {
                 m_fileTable = null;
@@ -406,6 +435,9 @@ namespace GitHub.DistributedTask.Pipelines
         [DataMember(Name = "EnvironmentVariables", EmitDefaultValue = false)]
         private List<TemplateToken> m_environmentVariables;
 
+        [DataMember(Name = "Defaults", EmitDefaultValue = false)]
+        private List<TemplateToken> m_defaults;
+
         [DataMember(Name = "FileTable", EmitDefaultValue = false)]
         private List<String> m_fileTable;
 

src/Sdk/DTPipelines/Pipelines/ObjectTemplating/PipelineTemplateConstants.cs

@@ -8,12 +8,14 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
     {
         public const String Always = "always";
         public const String BooleanStepsContext = "boolean-steps-context";
+        public const String BooleanStrategyContext = "boolean-strategy-context";
         public const String CancelTimeoutMinutes = "cancel-timeout-minutes";
         public const String Cancelled = "cancelled";
         public const String Checkout = "checkout";
         public const String Clean = "clean";
         public const String Container = "container";
         public const String ContinueOnError = "continue-on-error";
+        public const String Defaults = "defaults";
         public const String Env = "env";
         public const String Event = "event";
         public const String EventPattern = "github.event";
@@ -23,12 +25,15 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
         public const String FetchDepth = "fetch-depth";
         public const String GeneratedId = "generated-id";
         public const String GitHub = "github";
+        public const String HashFiles = "hashFiles";
         public const String Id = "id";
         public const String If = "if";
         public const String Image = "image";
         public const String Include = "include";
         public const String Inputs = "inputs";
         public const String Job = "job";
+        public const String JobDefaultsRun = "job-defaults-run";
+        public const String JobIfResult = "job-if-result";
         public const String JobOutputs = "job-outputs";
         public const String Jobs = "jobs";
         public const String Labels = "labels";
@@ -58,6 +63,7 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
         public const String Shell = "shell";
         public const String Skipped = "skipped";
         public const String StepEnv = "step-env";
+        public const String StepIfResult = "step-if-result";
         public const String Steps = "steps";
         public const String StepsScopeInputs = "steps-scope-inputs";
         public const String StepsScopeOutputs = "steps-scope-outputs";

src/Sdk/DTPipelines/Pipelines/ObjectTemplating/PipelineTemplateConverter.cs

@@ -16,6 +16,20 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 {
     internal static class PipelineTemplateConverter
     {
+        internal static Boolean ConvertToIfResult(
+            TemplateContext context,
+            TemplateToken ifResult)
+        {
+            var expression = ifResult.Traverse().FirstOrDefault(x => x is ExpressionToken);
+            if (expression != null)
+            {
+                throw new ArgumentException($"Unexpected type '{expression.GetType().Name}' encountered while reading 'if'.");
+            }
+
+            var evaluationResult = EvaluationResult.CreateIntermediateResult(null, ifResult);
+            return evaluationResult.IsTruthy;
+        }
+
         internal static Boolean? ConvertToStepContinueOnError(
             TemplateContext context,
             TemplateToken token,

src/Sdk/DTPipelines/Pipelines/ObjectTemplating/PipelineTemplateEvaluator.cs

@@ -4,7 +4,7 @@ using System.ComponentModel;
 using System.Linq;
 using System.Threading;
 using GitHub.DistributedTask.Expressions2;
-using GitHub.DistributedTask.Expressions2.Sdk;
+using GitHub.DistributedTask.Expressions2.Sdk.Functions;
 using GitHub.DistributedTask.ObjectTemplating;
 using GitHub.DistributedTask.ObjectTemplating.Schema;
 using GitHub.DistributedTask.ObjectTemplating.Tokens;
@@ -14,6 +14,9 @@ using ITraceWriter = GitHub.DistributedTask.ObjectTemplating.ITraceWriter;
 
 namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 {
+    /// <summary>
+    /// Evaluates parts of the workflow DOM. For example, a job strategy or step inputs.
+    /// </summary>
     [EditorBrowsable(EditorBrowsableState.Never)]
     public class PipelineTemplateEvaluator
     {
@@ -50,13 +53,14 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 
         public DictionaryContextData EvaluateStepScopeInputs(
             TemplateToken token,
-            DictionaryContextData contextData)
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
         {
             var result = default(DictionaryContextData);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.StepsScopeInputs, token, 0, null, omitHeader: true);
@@ -76,13 +80,14 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 
         public DictionaryContextData EvaluateStepScopeOutputs(
             TemplateToken token,
-            DictionaryContextData contextData)
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
         {
             var result = default(DictionaryContextData);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.StepsScopeOutputs, token, 0, null, omitHeader: true);
@@ -102,13 +107,14 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 
         public Boolean EvaluateStepContinueOnError(
             TemplateToken token,
-            DictionaryContextData contextData)
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
         {
             var result = default(Boolean?);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.BooleanStepsContext, token, 0, null, omitHeader: true);
@@ -126,16 +132,44 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
             return result ?? false;
         }
 
+        public String EvaluateStepDisplayName(
+            TemplateToken token,
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
+        {
+            var result = default(String);
+
+            if (token != null && token.Type != TokenType.Null)
+            {
+                var context = CreateContext(contextData, expressionFunctions);
+                try
+                {
+                    token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.StringStepsContext, token, 0, null, omitHeader: true);
+                    context.Errors.Check();
+                    result = PipelineTemplateConverter.ConvertToStepDisplayName(context, token);
+                }
+                catch (Exception ex) when (!(ex is TemplateValidationException))
+                {
+                    context.Errors.Add(ex);
+                }
+
+                context.Errors.Check();
+            }
+
+            return result;
+        }
+
         public Dictionary<String, String> EvaluateStepEnvironment(
             TemplateToken token,
             DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions,
             StringComparer keyComparer)
         {
             var result = default(Dictionary<String, String>);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.StepEnv, token, 0, null, omitHeader: true);
@@ -153,15 +187,44 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
             return result ?? new Dictionary<String, String>(keyComparer);
         }
 
+        public Boolean EvaluateStepIf(
+            TemplateToken token,
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions,
+            IEnumerable<KeyValuePair<String, Object>> expressionState)
+        {
+            var result = default(Boolean?);
+
+            if (token != null && token.Type != TokenType.Null)
+            {
+                var context = CreateContext(contextData, expressionFunctions, expressionState);
+                try
+                {
+                    token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.StepIfResult, token, 0, null, omitHeader: true);
+                    context.Errors.Check();
+                    result = PipelineTemplateConverter.ConvertToIfResult(context, token);
+                }
+                catch (Exception ex) when (!(ex is TemplateValidationException))
+                {
+                    context.Errors.Add(ex);
+                }
+
+                context.Errors.Check();
+            }
+
+            return result ?? throw new InvalidOperationException("Step if cannot be null");
+        }
+
         public Dictionary<String, String> EvaluateStepInputs(
             TemplateToken token,
-            DictionaryContextData contextData)
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
         {
             var result = default(Dictionary<String, String>);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.StepWith, token, 0, null, omitHeader: true);
@@ -181,13 +244,14 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 
         public Int32 EvaluateStepTimeout(
             TemplateToken token,
-            DictionaryContextData contextData)
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
         {
             var result = default(Int32?);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.NumberStepsContext, token, 0, null, omitHeader: true);
@@ -207,13 +271,14 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 
         public JobContainer EvaluateJobContainer(
             TemplateToken token,
-            DictionaryContextData contextData)
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
         {
             var result = default(JobContainer);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.Container, token, 0, null, omitHeader: true);
@@ -233,13 +298,14 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 
         public Dictionary<String, String> EvaluateJobOutput(
             TemplateToken token,
-            DictionaryContextData contextData)
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
         {
             var result = default(Dictionary<String, String>);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.JobOutputs, token, 0, null, omitHeader: true);
@@ -267,15 +333,53 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
             return result;
         }
 
+        public Dictionary<String, String> EvaluateJobDefaultsRun(
+            TemplateToken token,
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
+        {
+            var result = default(Dictionary<String, String>);
+
+            if (token != null && token.Type != TokenType.Null)
+            {
+                var context = CreateContext(contextData, expressionFunctions);
+                try
+                {
+                    token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.JobDefaultsRun, token, 0, null, omitHeader: true);
+                    context.Errors.Check();
+                    result = new Dictionary<String, String>(StringComparer.OrdinalIgnoreCase);
+                    var mapping = token.AssertMapping("defaults run");
+                    foreach (var pair in mapping)
+                    {
+                        // Literal key
+                        var key = pair.Key.AssertString("defaults run key");
+
+                        // Literal value
+                        var value = pair.Value.AssertString("defaults run value");
+                        result[key.Value] = value.Value;
+                    }
+                }
+                catch (Exception ex) when (!(ex is TemplateValidationException))
+                {
+                    context.Errors.Add(ex);
+                }
+
+                context.Errors.Check();
+            }
+
+            return result;
+        }
+
         public IList<KeyValuePair<String, JobContainer>> EvaluateJobServiceContainers(
             TemplateToken token,
-            DictionaryContextData contextData)
+            DictionaryContextData contextData,
+            IList<IFunctionInfo> expressionFunctions)
         {
             var result = default(List<KeyValuePair<String, JobContainer>>);
 
             if (token != null && token.Type != TokenType.Null)
             {
-                var context = CreateContext(contextData);
+                var context = CreateContext(contextData, expressionFunctions);
                 try
                 {
                     token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.Services, token, 0, null, omitHeader: true);
@@ -293,62 +397,10 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
             return result;
         }
 
-        public Boolean TryEvaluateStepDisplayName(
-            TemplateToken token,
+        private TemplateContext CreateContext(
             DictionaryContextData contextData,
-            out String stepName)
-        {
-            stepName = default(String);
-            var context = CreateContext(contextData);
-
-            if (token != null && token.Type != TokenType.Null)
-            {
-                // We should only evaluate basic expressions if we are sure we have context on all the Named Values and functions
-                // Otherwise return and use a default name
-                if (token is BasicExpressionToken expressionToken)
-                {
-                    ExpressionNode root = null;
-                    try
-                    {
-                        root = new ExpressionParser().ValidateSyntax(expressionToken.Expression, null) as ExpressionNode;
-                    }
-                    catch (Exception exception)
-                    {
-                        context.Errors.Add(exception);
-                        context.Errors.Check();
-                    }
-                    foreach (var node in root.Traverse())
-                    {
-                        if (node is NamedValue namedValue && !contextData.ContainsKey(namedValue.Name))
-                        {
-                            return false;
-                        }
-                        else if (node is Function function &&
-                            !context.ExpressionFunctions.Any(item => String.Equals(item.Name, function.Name)) &&
-                            !ExpressionConstants.WellKnownFunctions.ContainsKey(function.Name))
-                        {
-                            return false;
-                        }
-                    }
-                }
-
-                try
-                {
-                    token = TemplateEvaluator.Evaluate(context, PipelineTemplateConstants.StringStepsContext, token, 0, null, omitHeader: true);
-                    context.Errors.Check();
-                    stepName = PipelineTemplateConverter.ConvertToStepDisplayName(context, token);
-                }
-                catch (Exception ex) when (!(ex is TemplateValidationException))
-                {
-                    context.Errors.Add(ex);
-                }
-
-                context.Errors.Check();
-            }
-            return true;
-        }
-
-        private TemplateContext CreateContext(DictionaryContextData contextData)
+            IList<IFunctionInfo> expressionFunctions,
+            IEnumerable<KeyValuePair<String, Object>> expressionState = null)
         {
             var result = new TemplateContext
             {
@@ -371,7 +423,7 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
                 }
             }
 
-            // Add named context
+            // Add named values
             if (contextData != null)
             {
                 foreach (var pair in contextData)
@@ -380,14 +432,46 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
                 }
             }
 
-            // Compat for new agent against old server
-            foreach (var name in s_contextNames)
+            // Add functions
+            var functionNames = new HashSet<String>(StringComparer.OrdinalIgnoreCase);
+            if (expressionFunctions?.Count > 0)
+            {
+                foreach (var function in expressionFunctions)
+                {
+                    result.ExpressionFunctions.Add(function);
+                    functionNames.Add(function.Name);
+                }
+            }
+
+            // Add missing expression values and expression functions.
+            // This solves the following problems:
+            //   - Compat for new agent against old server (new contexts not sent down in job message)
+            //   - Evaluating early when all referenced contexts are available, even though all allowed
+            //     contexts may not yet be available. For example, evaluating step display name can often
+            //     be performed early.
+            foreach (var name in s_expressionValueNames)
             {
                 if (!result.ExpressionValues.ContainsKey(name))
                 {
                     result.ExpressionValues[name] = null;
                 }
             }
+            foreach (var name in s_expressionFunctionNames)
+            {
+                if (!functionNames.Contains(name))
+                {
+                    result.ExpressionFunctions.Add(new FunctionInfo<NoOperation>(name, 0, Int32.MaxValue));
+                }
+            }
+
+            // Add state
+            if (expressionState != null)
+            {
+                foreach (var pair in expressionState)
+                {
+                    result.State[pair.Key] = pair.Value;
+                }
+            }
 
             return result;
         }
@@ -395,9 +479,10 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
         private readonly ITraceWriter m_trace;
         private readonly TemplateSchema m_schema;
         private readonly IList<String> m_fileTable;
-        private readonly String[] s_contextNames = new[]
+        private readonly String[] s_expressionValueNames = new[]
         {
             PipelineTemplateConstants.GitHub,
+            PipelineTemplateConstants.Needs,
             PipelineTemplateConstants.Strategy,
             PipelineTemplateConstants.Matrix,
             PipelineTemplateConstants.Needs,
@@ -408,5 +493,13 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
             PipelineTemplateConstants.Runner,
             PipelineTemplateConstants.Env,
         };
+        private readonly String[] s_expressionFunctionNames = new[]
+        {
+            PipelineTemplateConstants.Always,
+            PipelineTemplateConstants.Cancelled,
+            PipelineTemplateConstants.Failure,
+            PipelineTemplateConstants.HashFiles,
+            PipelineTemplateConstants.Success,
+        };
     }
 }

src/Sdk/DTPipelines/Pipelines/ObjectTemplating/PipelineTemplateSchemaFactory.cs

@@ -2,25 +2,35 @@
 using System.ComponentModel;
 using System.IO;
 using System.Reflection;
+using System.Threading;
+using System.Threading.Tasks;
 using GitHub.DistributedTask.ObjectTemplating.Schema;
 
 namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
 {
     [EditorBrowsable(EditorBrowsableState.Never)]
-    public sealed class PipelineTemplateSchemaFactory
+    public static class PipelineTemplateSchemaFactory
     {
-        public TemplateSchema CreateSchema()
+        public static TemplateSchema GetSchema()
         {
-            var assembly = Assembly.GetExecutingAssembly();
-            var json = default(String);
-            using (var stream = assembly.GetManifestResourceStream("GitHub.DistributedTask.Pipelines.ObjectTemplating.workflow-v1.0.json"))
-            using (var streamReader = new StreamReader(stream))
+            if (s_schema == null)
             {
-                json = streamReader.ReadToEnd();
+                var assembly = Assembly.GetExecutingAssembly();
+                var json = default(String);
+                using (var stream = assembly.GetManifestResourceStream("GitHub.DistributedTask.Pipelines.ObjectTemplating.workflow-v1.0.json"))
+                using (var streamReader = new StreamReader(stream))
+                {
+                    json = streamReader.ReadToEnd();
+                }
+
+                var objectReader = new JsonObjectReader(null, json);
+                var schema = TemplateSchema.Load(objectReader);
+                Interlocked.CompareExchange(ref s_schema, schema, null);
             }
 
-            var objectReader = new JsonObjectReader(null, json);
-            return TemplateSchema.Load(objectReader);
+            return s_schema;
         }
+
+        private static TemplateSchema s_schema;
     }
 }

src/Sdk/DTPipelines/Pipelines/ObjectTemplating/YamlObjectReader.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Globalization;
 using System.IO;
 using System.Linq;
@@ -12,7 +12,7 @@ namespace GitHub.DistributedTask.Pipelines.ObjectTemplating
     /// <summary>
     /// Converts a YAML file into a TemplateToken
     /// </summary>
-    public sealed class YamlObjectReader : IObjectReader
+    internal sealed class YamlObjectReader : IObjectReader
     {
         internal YamlObjectReader(
             Int32? fileId,

src/Sdk/DTPipelines/workflow-v1.0.json

@@ -9,6 +9,7 @@
         "properties": {
           "on": "any",
           "name": "string",
+          "defaults": "workflow-defaults",
           "env": "workflow-env",
           "jobs": "jobs"
         }
@@ -37,8 +38,8 @@
     "steps-scope-input-value": {
       "context": [
         "github",
-        "strategy",
         "needs",
+        "strategy",
         "matrix",
         "secrets",
         "steps",
@@ -65,9 +66,9 @@
     "steps-scope-output-value": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "inputs",
@@ -90,9 +91,9 @@
       "description": "Default input values for a steps template",
       "context": [
         "github",
+        "needs",
         "strategy",
-        "matrix",
-        "needs"
+        "matrix"
       ],
       "one-of": [
         "string",
@@ -113,9 +114,9 @@
       "description": "Output values for a steps template",
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "job",
@@ -125,6 +126,23 @@
       "string": {}
     },
 
+    "workflow-defaults": {
+      "mapping": {
+        "properties": {
+          "run": "workflow-defaults-run"
+        }
+      }
+    },
+
+    "workflow-defaults-run": {
+      "mapping": {
+        "properties": {
+          "shell": "non-empty-string",
+          "working-directory": "non-empty-string"
+        }
+      }
+    },
+
     "workflow-env": {
       "context": [
         "github",
@@ -161,6 +179,7 @@
           "services": "services",
           "env": "job-env",
           "outputs": "job-outputs",
+          "defaults": "job-defaults",
           "steps": "steps"
         }
       }
@@ -185,6 +204,25 @@
       "string": {}
     },
 
+    "job-if-result": {
+      "context": [
+        "github",
+        "needs",
+        "always(0,0)",
+        "failure(0,MAX)",
+        "cancelled(0,0)",
+        "success(0,MAX)"
+      ],
+      "one-of": [
+        "null",
+        "boolean",
+        "number",
+        "string",
+        "sequence",
+        "mapping"
+      ]
+    },
+
     "strategy": {
       "context": [
         "github",
@@ -253,9 +291,9 @@
     "runs-on": {
       "context": [
         "github",
+        "needs",
         "strategy",
-        "matrix",
-        "needs"
+        "matrix"
       ],
       "one-of": [
         "non-empty-string",
@@ -278,10 +316,10 @@
     "job-env": {
       "context": [
         "github",
-        "secrets",
+        "needs",
         "strategy",
         "matrix",
-        "needs"
+        "secrets"
       ],
       "mapping": {
         "loose-key-type": "non-empty-string",
@@ -289,6 +327,30 @@
       }
     },
 
+    "job-defaults": {
+      "mapping": {
+        "properties": {
+          "run": "job-defaults-run"
+        }
+      }
+    },
+
+    "job-defaults-run": {
+      "context": [
+        "github",
+        "strategy",
+        "matrix",
+        "needs",
+        "env"
+      ],
+      "mapping": {
+        "properties": {
+          "shell": "non-empty-string",
+          "working-directory": "non-empty-string"
+        }
+      }
+    },
+
     "job-outputs": {
       "mapping": {
         "loose-key-type": "non-empty-string",
@@ -401,9 +463,9 @@
     "step-if": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "steps",
         "job",
         "runner",
@@ -411,7 +473,8 @@
         "always(0,0)",
         "failure(0,0)",
         "cancelled(0,0)",
-        "success(0,0)"
+        "success(0,0)",
+        "hashFiles(1,255)"
       ],
       "string": {}
     },
@@ -419,9 +482,9 @@
     "step-if-in-template": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "steps",
         "inputs",
         "job",
@@ -430,11 +493,63 @@
         "always(0,0)",
         "failure(0,0)",
         "cancelled(0,0)",
-        "success(0,0)"
+        "success(0,0)",
+        "hashFiles(1,255)"
       ],
       "string": {}
     },
 
+    "step-if-result": {
+      "context": [
+        "github",
+        "strategy",
+        "matrix",
+        "steps",
+        "job",
+        "runner",
+        "env",
+        "always(0,0)",
+        "failure(0,0)",
+        "cancelled(0,0)",
+        "success(0,0)",
+        "hashFiles(1,255)"
+      ],
+      "one-of": [
+        "null",
+        "boolean",
+        "number",
+        "string",
+        "sequence",
+        "mapping"
+      ]
+    },
+
+    "step-if-result-in-template": {
+      "context": [
+        "github",
+        "strategy",
+        "matrix",
+        "steps",
+        "inputs",
+        "job",
+        "runner",
+        "env",
+        "always(0,0)",
+        "failure(0,0)",
+        "cancelled(0,0)",
+        "success(0,0)",
+        "hashFiles(1,255)"
+      ],
+      "one-of": [
+        "null",
+        "boolean",
+        "number",
+        "string",
+        "sequence",
+        "mapping"
+      ]
+    },
+
     "steps-template-reference": {
       "mapping": {
         "properties": {
@@ -458,9 +573,9 @@
     "steps-template-reference-inputs": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "job",
@@ -476,9 +591,9 @@
     "steps-template-reference-inputs-in-template": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "inputs",
@@ -495,14 +610,15 @@
     "step-env": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
       ],
       "mapping": {
         "loose-key-type": "non-empty-string",
@@ -513,15 +629,16 @@
     "step-env-in-template": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "inputs",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
       ],
       "mapping": {
         "loose-key-type": "non-empty-string",
@@ -532,14 +649,35 @@
     "step-with": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
+      ],
+      "mapping": {
+        "loose-key-type": "non-empty-string",
+        "loose-value-type": "string"
+      }
+    },
+
+    "step-with-in-template": {
+      "context": [
+        "github",
+        "needs",
+        "strategy",
+        "matrix",
+        "secrets",
+        "steps",
+        "inputs",
+        "job",
+        "runner",
+        "env",
+        "hashFiles(1,255)"
       ],
       "mapping": {
         "loose-key-type": "non-empty-string",
@@ -550,9 +688,9 @@
     "container": {
       "context": [
         "github",
+        "needs",
         "strategy",
-        "matrix",
-        "needs"
+        "matrix"
       ],
       "one-of": [
         "string",
@@ -575,9 +713,9 @@
     "services": {
       "context": [
         "github",
+        "needs",
         "strategy",
-        "matrix",
-        "needs"
+        "matrix"
       ],
       "mapping": {
         "loose-key-type": "non-empty-string",
@@ -588,9 +726,9 @@
     "services-container": {
       "context": [
         "github",
+        "needs",
         "strategy",
-        "matrix",
-        "needs"
+        "matrix"
       ],
       "one-of": [
         "non-empty-string",
@@ -601,29 +739,10 @@
     "container-env": {
       "mapping": {
         "loose-key-type": "non-empty-string",
-        "loose-value-type": "string"
+        "loose-value-type": "string-runner-context"
       }
     },
 
-    "step-with-in-template": {
-        "context": [
-          "github",
-          "strategy",
-          "matrix",
-          "needs",
-          "secrets",
-          "steps",
-          "inputs",
-          "job",
-          "runner",
-          "env"
-        ],
-        "mapping": {
-          "loose-key-type": "non-empty-string",
-          "loose-value-type": "string"
-        }
-      },
-  
     "non-empty-string": {
       "string": {
         "require-non-empty": true
@@ -639,9 +758,9 @@
     "boolean-strategy-context": {
       "context": [
         "github",
+        "needs",
         "strategy",
-        "matrix",
-        "needs"
+        "matrix"
       ],
       "boolean": {}
     },
@@ -649,9 +768,9 @@
     "number-strategy-context": {
       "context": [
         "github",
+        "needs",
         "strategy",
-        "matrix",
-        "needs"
+        "matrix"
       ],
       "number": {}
     },
@@ -659,9 +778,9 @@
     "string-strategy-context": {
       "context": [
         "github",
+        "needs",
         "strategy",
-        "matrix",
-        "needs"
+        "matrix"
       ],
       "string": {}
     },
@@ -669,14 +788,15 @@
     "boolean-steps-context": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
       ],
       "boolean": {}
     },
@@ -684,15 +804,16 @@
     "boolean-steps-context-in-template": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "inputs",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
       ],
       "boolean": {}
     },
@@ -700,14 +821,15 @@
     "number-steps-context": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
       ],
       "number": {}
     },
@@ -715,15 +837,16 @@
     "number-steps-context-in-template": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "inputs",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
       ],
       "number": {}
     },
@@ -731,9 +854,9 @@
     "string-runner-context": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "job",
@@ -746,14 +869,15 @@
     "string-steps-context": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
       ],
       "string": {}
     },
@@ -761,15 +885,16 @@
     "string-steps-context-in-template": {
       "context": [
         "github",
+        "needs",
         "strategy",
         "matrix",
-        "needs",
         "secrets",
         "steps",
         "inputs",
         "job",
         "runner",
-        "env"
+        "env",
+        "hashFiles(1,255)"
       ],
       "string": {}
     }

src/Test/L0/Listener/Configuration/ConfigurationManagerL0.cs

@@ -37,7 +37,7 @@ namespace GitHub.Runner.Common.Tests.Listener.Configuration
 
         private Mock<IRSAKeyManager> _rsaKeyManager;
         private string _expectedToken = "expectedToken";
-        private string _expectedServerUrl = "https://localhost";
+        private string _expectedServerUrl = "https://codedev.ms";
         private string _expectedAgentName = "expectedAgentName";
         private string _expectedPoolName = "poolName";
         private string _expectedAuthType = "pat";

src/Test/L0/Listener/JobDispatcherL0.cs

@@ -33,7 +33,7 @@ namespace GitHub.Runner.Common.Tests.Listener
             TaskOrchestrationPlanReference plan = new TaskOrchestrationPlanReference();
             TimelineReference timeline = null;
             Guid jobId = Guid.NewGuid();
-            var result = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, "someJob", "someJob", null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null);
+            var result = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, "someJob", "someJob", null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null, null);
             result.ContextData["github"] = new Pipelines.ContextData.DictionaryContextData();
             return result;
         }

src/Test/L0/Listener/RunnerL0.cs

@@ -43,7 +43,7 @@ namespace GitHub.Runner.Common.Tests.Listener
             TaskOrchestrationPlanReference plan = new TaskOrchestrationPlanReference();
             TimelineReference timeline = null;
             Guid jobId = Guid.NewGuid();
-            return new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, "test", "test", null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null);
+            return new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, "test", "test", null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null, null);
         }
 
         private JobCancelMessage CreateJobCancelMessage()

src/Test/L0/Worker/ActionCommandManagerL0.cs

@@ -150,7 +150,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                 TimelineReference timeline = new TimelineReference();
                 Guid jobId = Guid.NewGuid();
                 string jobName = "some job name";
-                var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, jobName, jobName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null);
+                var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, jobName, jobName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null, null);
                 jobRequest.Resources.Repositories.Add(new Pipelines.RepositoryResource()
                 {
                     Alias = Pipelines.PipelineConstants.SelfAlias,

src/Test/L0/Worker/ActionManagerL0.cs

@@ -1,4 +1,6 @@
-using GitHub.DistributedTask.ObjectTemplating.Tokens;
+using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.ObjectTemplating.Tokens;
+using GitHub.DistributedTask.Pipelines.ContextData;
 using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Common.Util;
 using GitHub.Runner.Worker;
@@ -109,6 +111,57 @@ namespace GitHub.Runner.Common.Tests.Worker
             }
         }
 
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        public async void PrepareActions_SkipDownloadActionFromGraphWhenCached_OnPremises()
+        {
+            try
+            {
+                // Arrange
+                Setup();
+                var actionId = Guid.NewGuid();
+                var actions = new List<Pipelines.ActionStep>
+                {
+                    new Pipelines.ActionStep()
+                    {
+                        Name = "action",
+                        Id = actionId,
+                        Reference = new Pipelines.RepositoryPathReference()
+                        {
+                            Name = "actions/no-such-action",
+                            Ref = "master",
+                            RepositoryType = "GitHub"
+                        }
+                    }
+                };
+                _configurationStore.Object.GetSettings().IsHostedServer = false;
+                var actionDirectory = Path.Combine(_hc.GetDirectory(WellKnownDirectory.Actions), "actions/no-such-action", "master");
+                Directory.CreateDirectory(actionDirectory);
+                var watermarkFile = $"{actionDirectory}.completed";
+                File.WriteAllText(watermarkFile, DateTime.UtcNow.ToString());
+                var actionFile = Path.Combine(actionDirectory, "action.yml");
+                File.WriteAllText(actionFile, @"
+name: ""no-such-action""
+runs:
+  using: node12
+  main: no-such-action.js
+");
+                var testFile = Path.Combine(actionDirectory, "test-file");
+                File.WriteAllText(testFile, "asdf");
+
+                // Act
+                await _actionManager.PrepareActionsAsync(_ec.Object, actions);
+
+                // Assert
+                Assert.True(File.Exists(testFile));
+            }
+            finally
+            {
+                Teardown();
+            }
+        }
+
         [Fact]
         [Trait("Level", "L0")]
         [Trait("Category", "Worker")]
@@ -1600,6 +1653,8 @@ runs:
             _ec = new Mock<IExecutionContext>();
             _ec.Setup(x => x.CancellationToken).Returns(_ecTokenSource.Token);
             _ec.Setup(x => x.Variables).Returns(new Variables(_hc, new Dictionary<string, VariableValue>()));
+            _ec.Setup(x => x.ExpressionValues).Returns(new DictionaryContextData());
+            _ec.Setup(x => x.ExpressionFunctions).Returns(new List<IFunctionInfo>());
             _ec.Setup(x => x.Write(It.IsAny<string>(), It.IsAny<string>())).Callback((string tag, string message) => { _hc.GetTrace().Info($"[{tag}]{message}"); });
             _ec.Setup(x => x.AddIssue(It.IsAny<Issue>(), It.IsAny<string>())).Callback((Issue issue, string message) => { _hc.GetTrace().Info($"[{issue.Type}]{issue.Message ?? message}"); });
             _ec.Setup(x => x.GetGitHubContext("workspace")).Returns(Path.Combine(_workFolder, "actions", "actions"));

src/Test/L0/Worker/ActionManifestManagerL0.cs

@@ -1,7 +1,9 @@
+using GitHub.DistributedTask.Expressions2;
 using GitHub.DistributedTask.ObjectTemplating.Tokens;
 using GitHub.DistributedTask.Pipelines.ContextData;
 using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Worker;
+using GitHub.Runner.Worker.Expressions;
 using Moq;
 using System;
 using System.Collections.Generic;
@@ -533,26 +535,26 @@ namespace GitHub.Runner.Common.Tests.Worker
                 var actionManifest = new ActionManifestManager();
                 actionManifest.Initialize(_hc);
 
-                var githubContext = new DictionaryContextData();
-                githubContext.Add("ref", new StringContextData("refs/heads/master"));
-
-                var evaluateContext = new Dictionary<string, PipelineContextData>(StringComparer.OrdinalIgnoreCase);
-                evaluateContext["github"] = githubContext;
-                evaluateContext["strategy"] = new DictionaryContextData();
-                evaluateContext["matrix"] = new DictionaryContextData();
-                evaluateContext["steps"] = new DictionaryContextData();
-                evaluateContext["job"] = new DictionaryContextData();
-                evaluateContext["runner"] = new DictionaryContextData();
-                evaluateContext["env"] = new DictionaryContextData();
+                _ec.Object.ExpressionValues["github"] = new DictionaryContextData
+                {
+                    { "ref", new StringContextData("refs/heads/master") },
+                };
+                _ec.Object.ExpressionValues["strategy"] = new DictionaryContextData();
+                _ec.Object.ExpressionValues["matrix"] = new DictionaryContextData();
+                _ec.Object.ExpressionValues["steps"] = new DictionaryContextData();
+                _ec.Object.ExpressionValues["job"] = new DictionaryContextData();
+                _ec.Object.ExpressionValues["runner"] = new DictionaryContextData();
+                _ec.Object.ExpressionValues["env"] = new DictionaryContextData();
+                _ec.Object.ExpressionFunctions.Add(new FunctionInfo<HashFilesFunction>("hashFiles", 1, 255));
 
                 //Act
-                var result = actionManifest.EvaluateDefaultInput(_ec.Object, "testInput", new StringToken(null, null, null, "defaultValue"), evaluateContext);
+                var result = actionManifest.EvaluateDefaultInput(_ec.Object, "testInput", new StringToken(null, null, null, "defaultValue"));
 
                 //Assert
                 Assert.Equal("defaultValue", result);
 
                 //Act
-                result = actionManifest.EvaluateDefaultInput(_ec.Object, "testInput", new BasicExpressionToken(null, null, null, "github.ref"), evaluateContext);
+                result = actionManifest.EvaluateDefaultInput(_ec.Object, "testInput", new BasicExpressionToken(null, null, null, "github.ref"));
 
                 //Assert
                 Assert.Equal("refs/heads/master", result);
@@ -575,6 +577,8 @@ namespace GitHub.Runner.Common.Tests.Worker
             _ec.Setup(x => x.WriteDebug).Returns(true);
             _ec.Setup(x => x.CancellationToken).Returns(_ecTokenSource.Token);
             _ec.Setup(x => x.Variables).Returns(new Variables(_hc, new Dictionary<string, VariableValue>()));
+            _ec.Setup(x => x.ExpressionValues).Returns(new DictionaryContextData());
+            _ec.Setup(x => x.ExpressionFunctions).Returns(new List<IFunctionInfo>());
             _ec.Setup(x => x.Write(It.IsAny<string>(), It.IsAny<string>())).Callback((string tag, string message) => { _hc.GetTrace().Info($"{tag}{message}"); });
             _ec.Setup(x => x.AddIssue(It.IsAny<Issue>(), It.IsAny<string>())).Callback((Issue issue, string message) => { _hc.GetTrace().Info($"[{issue.Type}]{issue.Message ?? message}"); });
         }

src/Test/L0/Worker/ActionRunnerL0.cs

@@ -1,4 +1,5 @@
-using GitHub.DistributedTask.ObjectTemplating.Tokens;
+using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.ObjectTemplating.Tokens;
 using GitHub.DistributedTask.Pipelines;
 using GitHub.DistributedTask.Pipelines.ContextData;
 using GitHub.DistributedTask.WebApi;
@@ -322,6 +323,7 @@ namespace GitHub.Runner.Common.Tests.Worker
 
             _ec = new Mock<IExecutionContext>();
             _ec.Setup(x => x.ExpressionValues).Returns(_context);
+            _ec.Setup(x => x.ExpressionFunctions).Returns(new List<IFunctionInfo>());
             _ec.Setup(x => x.IntraActionState).Returns(new Dictionary<string, string>());
             _ec.Setup(x => x.EnvironmentVariables).Returns(new Dictionary<string, string>());
             _ec.Setup(x => x.SetGitHubContext(It.IsAny<string>(), It.IsAny<string>()));

src/Test/L0/Worker/ExecutionContextL0.cs

@@ -25,7 +25,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                 TimelineReference timeline = new TimelineReference();
                 Guid jobId = Guid.NewGuid();
                 string jobName = "some job name";
-                var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, jobName, jobName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null);
+                var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, jobName, jobName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null, null);
                 jobRequest.Resources.Repositories.Add(new Pipelines.RepositoryResource()
                 {
                     Alias = Pipelines.PipelineConstants.SelfAlias,
@@ -101,7 +101,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                 TimelineReference timeline = new TimelineReference();
                 Guid jobId = Guid.NewGuid();
                 string jobName = "some job name";
-                var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, jobName, jobName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null);
+                var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, jobName, jobName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null, null);
                 jobRequest.Resources.Repositories.Add(new Pipelines.RepositoryResource()
                 {
                     Alias = Pipelines.PipelineConstants.SelfAlias,
@@ -152,7 +152,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                 TimelineReference timeline = new TimelineReference();
                 Guid jobId = Guid.NewGuid();
                 string jobName = "some job name";
-                var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, jobName, jobName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null);
+                var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, jobName, jobName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null, null);
                 jobRequest.Resources.Repositories.Add(new Pipelines.RepositoryResource()
                 {
                     Alias = Pipelines.PipelineConstants.SelfAlias,

src/Test/L0/Worker/Expressions/ConditionFunctionsL0.cs

@@ -1,20 +1,20 @@
 using System;
 using System.Collections.Generic;
 using System.Runtime.CompilerServices;
+using GitHub.DistributedTask.Expressions2;
+using GitHub.DistributedTask.ObjectTemplating;
+using GitHub.DistributedTask.Pipelines.ObjectTemplating;
 using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Worker;
+using GitHub.Runner.Worker.Expressions;
 using Moq;
 using Xunit;
-using GitHub.DistributedTask.Expressions2;
-using GitHub.DistributedTask.Pipelines.ContextData;
 
-namespace GitHub.Runner.Common.Tests.Worker
+namespace GitHub.Runner.Common.Tests.Worker.Expressions
 {
-    public sealed class ExpressionManagerL0
+    public sealed class ConditionFunctionsL0
     {
-        private Mock<IExecutionContext> _ec;
-        private ExpressionManager _expressionManager;
-        private DictionaryContextData _expressions;
+        private TemplateContext _templateContext;
         private JobContext _jobContext;
 
         [Fact]
@@ -38,7 +38,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                     _jobContext.Status = variableSet.JobStatus;
 
                     // Act.
-                    bool actual = _expressionManager.Evaluate(_ec.Object, "always()").Value;
+                    bool actual = Evaluate("always()");
 
                     // Assert.
                     Assert.Equal(variableSet.Expected, actual);
@@ -68,7 +68,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                     _jobContext.Status = variableSet.JobStatus;
 
                     // Act.
-                    bool actual = _expressionManager.Evaluate(_ec.Object, "cancelled()").Value;
+                    bool actual = Evaluate("cancelled()");
 
                     // Assert.
                     Assert.Equal(variableSet.Expected, actual);
@@ -97,7 +97,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                     _jobContext.Status = variableSet.JobStatus;
 
                     // Act.
-                    bool actual = _expressionManager.Evaluate(_ec.Object, "failure()").Value;
+                    bool actual = Evaluate("failure()");
 
                     // Assert.
                     Assert.Equal(variableSet.Expected, actual);
@@ -126,37 +126,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                     _jobContext.Status = variableSet.JobStatus;
 
                     // Act.
-                    bool actual = _expressionManager.Evaluate(_ec.Object, "success()").Value;
-
-                    // Assert.
-                    Assert.Equal(variableSet.Expected, actual);
-                }
-            }
-        }
-
-        [Fact]
-        [Trait("Level", "L0")]
-        [Trait("Category", "Worker")]
-        public void ContextNamedValue()
-        {
-            using (TestHostContext hc = CreateTestContext())
-            {
-                // Arrange.
-                var variableSets = new[]
-                {
-                    new { Condition = "github.ref == 'refs/heads/master'", VariableName = "ref", VariableValue = "refs/heads/master", Expected = true },
-                    new { Condition = "github['ref'] == 'refs/heads/master'", VariableName = "ref", VariableValue = "refs/heads/master", Expected = true },
-                    new { Condition = "github.nosuch || '' == ''", VariableName = "ref", VariableValue = "refs/heads/master", Expected = true },
-                    new { Condition = "github['ref'] == 'refs/heads/release'", VariableName = "ref", VariableValue = "refs/heads/master", Expected = false },
-                    new { Condition = "github.ref == 'refs/heads/release'", VariableName = "ref", VariableValue = "refs/heads/master", Expected = false },
-                };
-                foreach (var variableSet in variableSets)
-                {
-                    InitializeExecutionContext(hc);
-                    _ec.Object.ExpressionValues["github"] = new GitHubContext() { { variableSet.VariableName, new StringContextData(variableSet.VariableValue) } };
-
-                    // Act.
-                    bool actual = _expressionManager.Evaluate(_ec.Object, variableSet.Condition).Value;
+                    bool actual = Evaluate("success()");
 
                     // Assert.
                     Assert.Equal(variableSet.Expected, actual);
@@ -166,21 +136,34 @@ namespace GitHub.Runner.Common.Tests.Worker
 
         private TestHostContext CreateTestContext([CallerMemberName] String testName = "")
         {
-            var hc = new TestHostContext(this, testName);
-            _expressionManager = new ExpressionManager();
-            _expressionManager.Initialize(hc);
-            return hc;
+            return new TestHostContext(this, testName);
         }
 
         private void InitializeExecutionContext(TestHostContext hc)
         {
-            _expressions = new DictionaryContextData();
             _jobContext = new JobContext();
 
-            _ec = new Mock<IExecutionContext>();
-            _ec.SetupAllProperties();
-            _ec.Setup(x => x.ExpressionValues).Returns(_expressions);
-            _ec.Setup(x => x.JobContext).Returns(_jobContext);
+            var executionContext = new Mock<IExecutionContext>();
+            executionContext.SetupAllProperties();
+            executionContext.Setup(x => x.JobContext).Returns(_jobContext);
+
+            _templateContext = new TemplateContext();
+            _templateContext.State[nameof(IExecutionContext)] = executionContext.Object;
+        }
+
+        private bool Evaluate(string expression)
+        {
+            var parser = new ExpressionParser();
+            var functions = new IFunctionInfo[]
+            {
+                new FunctionInfo<AlwaysFunction>(PipelineTemplateConstants.Always, 0, 0),
+                new FunctionInfo<CancelledFunction>(PipelineTemplateConstants.Cancelled, 0, 0),
+                new FunctionInfo<FailureFunction>(PipelineTemplateConstants.Failure, 0, 0),
+                new FunctionInfo<SuccessFunction>(PipelineTemplateConstants.Success, 0, 0),
+            };
+            var tree = parser.CreateTree(expression, null, null, functions);
+            var result = tree.Evaluate(null, null, _templateContext, null);
+            return result.IsTruthy;
         }
     }
 }

src/Test/L0/Worker/JobExtensionL0.cs

@@ -22,7 +22,6 @@ namespace GitHub.Runner.Common.Tests.Worker
         private Mock<IJobServerQueue> _jobServerQueue;
         private Mock<IConfigurationStore> _config;
         private Mock<IPagingLogger> _logger;
-        private Mock<IExpressionManager> _express;
         private Mock<IContainerOperationProvider> _containerProvider;
         private Mock<IDiagnosticLogManager> _diagnosticLogManager;
 
@@ -35,7 +34,6 @@ namespace GitHub.Runner.Common.Tests.Worker
             _jobServerQueue = new Mock<IJobServerQueue>();
             _config = new Mock<IConfigurationStore>();
             _logger = new Mock<IPagingLogger>();
-            _express = new Mock<IExpressionManager>();
             _containerProvider = new Mock<IContainerOperationProvider>();
             _diagnosticLogManager = new Mock<IDiagnosticLogManager>();
             _directoryManager = new Mock<IPipelineDirectoryManager>();
@@ -100,7 +98,7 @@ namespace GitHub.Runner.Common.Tests.Worker
             };
 
             Guid jobId = Guid.NewGuid();
-            _message = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, "test", "test", null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), steps, null, null, null);
+            _message = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, "test", "test", null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), steps, null, null, null, null);
             GitHubContext github = new GitHubContext();
             github["repository"] = new Pipelines.ContextData.StringContextData("actions/runner");
             _message.ContextData.Add("github", github);
@@ -108,7 +106,6 @@ namespace GitHub.Runner.Common.Tests.Worker
             hc.SetSingleton(_actionManager.Object);
             hc.SetSingleton(_config.Object);
             hc.SetSingleton(_jobServerQueue.Object);
-            hc.SetSingleton(_express.Object);
             hc.SetSingleton(_containerProvider.Object);
             hc.SetSingleton(_directoryManager.Object);
             hc.SetSingleton(_diagnosticLogManager.Object);

src/Test/L0/Worker/JobRunnerL0.cs

@@ -53,9 +53,6 @@ namespace GitHub.Runner.Common.Tests.Worker
             }
 
             _tokenSource = new CancellationTokenSource();
-            var expressionManager = new ExpressionManager();
-            expressionManager.Initialize(hc);
-            hc.SetSingleton<IExpressionManager>(expressionManager);
 
             _jobRunner = new JobRunner();
             _jobRunner.Initialize(hc);
@@ -63,7 +60,7 @@ namespace GitHub.Runner.Common.Tests.Worker
             TaskOrchestrationPlanReference plan = new TaskOrchestrationPlanReference();
             TimelineReference timeline = new Timeline(Guid.NewGuid());
             Guid jobId = Guid.NewGuid();
-            _message = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, testName, testName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null);
+            _message = new Pipelines.AgentJobRequestMessage(plan, timeline, jobId, testName, testName, null, null, null, new Dictionary<string, VariableValue>(), new List<MaskHint>(), new Pipelines.JobResources(), new Pipelines.ContextData.DictionaryContextData(), new Pipelines.WorkspaceOptions(), new List<Pipelines.ActionStep>(), null, null, null, null);
             _message.Variables[Constants.Variables.System.Culture] = "en-US";
             _message.Resources.Endpoints.Add(new ServiceEndpoint()
             {

src/Test/L0/Worker/StepsRunnerL0.cs

@@ -1,17 +1,17 @@
-using GitHub.DistributedTask.WebApi;
-using GitHub.Runner.Worker;
-using Moq;
-using System;
+using System;
 using System.Collections.Generic;
 using System.Globalization;
 using System.Linq;
 using System.Runtime.CompilerServices;
 using System.Threading.Tasks;
+using Moq;
 using Xunit;
 using GitHub.DistributedTask.Expressions2;
 using GitHub.DistributedTask.Pipelines.ContextData;
 using GitHub.DistributedTask.ObjectTemplating.Tokens;
+using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Common.Util;
+using GitHub.Runner.Worker;
 
 namespace GitHub.Runner.Common.Tests.Worker
 {
@@ -27,9 +27,6 @@ namespace GitHub.Runner.Common.Tests.Worker
         private TestHostContext CreateTestContext([CallerMemberName] String testName = "")
         {
             var hc = new TestHostContext(this, testName);
-            var expressionManager = new ExpressionManager();
-            expressionManager.Initialize(hc);
-            hc.SetSingleton<IExpressionManager>(expressionManager);
             Dictionary<string, VariableValue> variablesToCopy = new Dictionary<string, VariableValue>();
             _variables = new Variables(
                 hostContext: hc,
@@ -49,6 +46,7 @@ namespace GitHub.Runner.Common.Tests.Worker
             _contexts["runner"] = new DictionaryContextData();
             _contexts["job"] = _jobContext;
             _ec.Setup(x => x.ExpressionValues).Returns(_contexts);
+            _ec.Setup(x => x.ExpressionFunctions).Returns(new List<IFunctionInfo>());
             _ec.Setup(x => x.JobContext).Returns(_jobContext);
 
             _stepContext = new StepsContext();
@@ -383,16 +381,11 @@ namespace GitHub.Runner.Common.Tests.Worker
         {
             using (TestHostContext hc = CreateTestContext())
             {
-                var expressionManager = new Mock<IExpressionManager>();
-                expressionManager.Object.Initialize(hc);
-                hc.SetSingleton<IExpressionManager>(expressionManager.Object);
-                expressionManager.Setup(x => x.Evaluate(It.IsAny<IExecutionContext>(), It.IsAny<string>(), It.IsAny<bool>())).Throws(new Exception());
-
                 // Arrange.
                 var variableSets = new[]
                 {
-                    new[] { CreateStep(hc, TaskResult.Succeeded, "success()") },
-                    new[] { CreateStep(hc, TaskResult.Succeeded, "success()") },
+                    new[] { CreateStep(hc, TaskResult.Succeeded, "fromJson('not json')") },
+                    new[] { CreateStep(hc, TaskResult.Succeeded, "fromJson('not json')") },
                 };
                 foreach (var variableSet in variableSets)
                 {
@@ -610,6 +603,7 @@ namespace GitHub.Runner.Common.Tests.Worker
             stepContext.Setup(x => x.Variables).Returns(_variables);
             stepContext.Setup(x => x.EnvironmentVariables).Returns(_env);
             stepContext.Setup(x => x.ExpressionValues).Returns(_contexts);
+            stepContext.Setup(x => x.ExpressionFunctions).Returns(new List<IFunctionInfo>());
             stepContext.Setup(x => x.JobContext).Returns(_jobContext);
             stepContext.Setup(x => x.StepsContext).Returns(_stepContext);
             stepContext.Setup(x => x.ContextName).Returns(step.Object.Action.ContextName);

src/Test/L0/Worker/WorkerL0.cs

@@ -67,7 +67,7 @@ namespace GitHub.Runner.Common.Tests.Worker
                     new Pipelines.ContextData.DictionaryContextData()
                 },
             };
-            var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, JobId, jobName, jobName, new StringToken(null, null, null, "ubuntu"), sidecarContainers, null, variables, new List<MaskHint>(), resources, context, null, actions, null, null, null);
+            var jobRequest = new Pipelines.AgentJobRequestMessage(plan, timeline, JobId, jobName, jobName, new StringToken(null, null, null, "ubuntu"), sidecarContainers, null, variables, new List<MaskHint>(), resources, context, null, actions, null, null, null, null);
             return jobRequest;
         }
 

src/runnerversion

@@ -1 +1 @@
-2.165.2
+2.169.0