Update releaseVersion

* set env in ProcessInvoker sanitized (#2280)

* set env in ProcessInvoker sanitized

* Update release notes and runnerversion

---------

Co-authored-by: Stefan Ruvceski <96768603+ruvceskistefan@users.noreply.github.com>

.github/workflows/release.yml

@@ -288,6 +288,7 @@ jobs:
         release_name: "v${{ steps.releaseNote.outputs.version }}"
         body: |
           ${{ steps.releaseNote.outputs.note }}
+        prerelease: true
 
     # Upload release assets (full runner packages)
     - name: Upload Release Asset (win-x64)

docs/adrs/1891-container-hooks.md

@@ -0,0 +1,596 @@
+# ADR 0000: Container Hooks
+
+**Date**: 2022-05-12
+
+**Status**: Accepted
+
+# Background
+
+[Job Hooks](https://github.com/actions/runner/blob/main/docs/adrs/1751-runner-job-hooks.md) have given users the ability to customize how their self hosted runners run a job.
+Users also want the ability to customize how they run containers during the scope of the job, rather then being locked into the docker implementation we have in the runner. They may want to use podman, kubernetes, or even change the docker commands we run. 
+We should give them that option, and publish examples how how they can create their own hooks.
+
+# Guiding Principles
+- **Extensibility** is the focus, we need to make sure we are flexible enough to cover current and future scenarios, even at the cost of making it harder to utilize these hooks
+- Args should map **directly** to yaml values provided by the user. 
+  - For example, the current runner overrides `HOME`, we can do that in the hook, but we shouldn't pass that hook as an ENV with the other env's the user has set, as that is not user input, it is how the runner invokes containers
+
+## Interface
+- You will set the variable `ACTIONS_RUNNER_CONTAINER_HOOK=/Users/foo/runner/hooks.js` which is the entrypoint to your hook handler.
+  - There is no partial opt in, you must handle every hook 
+- We will pass a command and some args via `stdin`
+- An exit code of 0 is a success, every other exit code is a failure
+- We will support the same runner commands we support in [Job Hooks](https://github.com/actions/runner/blob/main/docs/adrs/1751-runner-job-hooks.md)
+- On timeout, we will send a sigint to your process. If you fail to terminate within a reasonable amount of time, we will send a sigkill, and eventually kill the process tree.
+
+An example input looks like
+```json
+{
+  "command": "job_cleanup",
+  "responseFile": "/users/thboop/runner/_work/{guid}.json",
+  "args": {},
+  "state": 
+  {
+      "id": "82e8219701fe096a35941d869cf8d71af1d943b5d3bdd718850fb87ac3042480"
+  }
+}
+```
+
+`command` is the command we expect you to invoke
+`responseFile` is the file you need to write your output to, if the command has output
+`args` are the specific arguments the command needs
+`state` is a json blog you can pass around to maintain your state, this is covered in more details below.
+
+### Writing responses to a file
+All text written to stdout or stderr should appear in the job or step logs. With that in mind, we support a few ways to actually return data:
+1. Wrapping the json in some unique tag and processing it like we do commands
+2. Writing to a file
+
+For 1, users typically view logging information as a safe action, so we worry someone accidentialy logging unsantized information and causing unexpected or un-secure behavior. We eventually plan to move off of stdout/stderr style commands in favor of a runner cli. 
+Investing in this area doesn't make a lot of sense at this time.
+
+While writing to a file to communicate isn't the most ideal pattern, its an existing pattern in the runner and serves us well, so lets reuse it.
+
+### Output
+Your output must be correctly formatted json. An example output looks like:
+
+```
+{
+  "state": {},
+  "context"
+  {
+    "container" : 
+    {
+      "id": "82e8219701fe096a35941d869cf8d71af1d943b5d3bdd718850fb87ac3042480"
+      "network": "github_network_53269bd575974817b43f4733536b200c"
+    }
+    "services": {
+      "redis": {
+        "id": "60972d9aa486605e66b0dad4abb638dc3d9116f566579e418166eedb8abb9105",
+        "ports": {
+          "8080": "8080"
+        },
+      "network": "github_network_53269bd575974817b43f4733536b200c"
+    }
+  }
+  "alpine: true,
+}
+```
+
+`state` is a unique field any command can return. If it is not empty, we will store the state for you and pass it into all future commands. You can overwrite it by having the next hook invoked return a unique state.
+
+Other fields are dependent upon the command being run.
+
+### Versioning
+We will not version these hooks at launch. If needed, we can always major version split these hooks in the future. We will ship in Beta to allow for breaking changes for a few months.
+
+### The Job Context
+The [job context](https://docs.github.com/en/actions/learn-github-actions/contexts#example-contents-of-the-job-context) currently has a variety of fields that correspond to containers. We should consider allowing hooks to populate new fields in the job context. That is out of scope for this original release however.
+
+## Hooks
+Hooks are to be implemented at a very high level, and map to actions the runner does, rather then specific docker actions like `docker build` or `docker create`. By mapping to runner actions, we create a very extensible framework that is flexible enough to solve any user concerns in the future. By providing first party implementations, we give users easy starting points to customize specific hooks (like `docker build`) without having to write full blown solutions.
+
+The other would be to provide hooks that mirror every docker call we make, and expose more hooks to help support k8s users, with the expectation that users may have to no-op on multiple hooks if they don't correspond to our use case.
+
+Why we don't want to go that way
+- It feels clunky, users need to understand which hooks they need to implement and which they can ignore, which isn't a great UX
+- It doesn't scale well, I don't want to build a solution where we may need to add more hooks, by mapping to runner actions, updating hooks is a painful experience for users
+- Its overwhelming, its easier to tell users to build 4 hooks and track data themselves, rather then 16 hooks where the runner needs certain information and then needs to provide that information back into each hook. If we expose `Container Create`, you need to return the container you created, then we do `container run` which uses that container. If we just give you an image and say create and run this container, you don't need to store the container id in the runner, and it maps better to k8s scenarios where we don't really have container ids.
+
+### Prepare_job hook
+The `prepare_job` hook is called when a job is started. We pass in any job or service containers the job has. We expect that you:
+- Prune anything from previous jobs if needed
+- Create a network if needed
+- Pull the job and service containers
+- Start the job container
+- Start the service containers
+- Write to the response file some information we need
+  - Required: if the container is alpine, otherwise x64
+  - Optional: any context fields you want to set on the job context, otherwise they will be unavailable for users to use
+- Return 0 when the health checks have succeeded and the job/service containers are started
+
+This hook will **always** be called if you have container hooks enabled, even if no service or job containers exist in the job. This allows you to fail the job or implement a default job container if you want to and no job container has been provided.
+
+
+<details>
+<summary>Example Input</summary>
+<br>
+  
+```
+{
+  "command": "prepare_job",
+  "responseFile": "/users/thboop/runner/_work/{guid}.json",
+  "state": {},
+  "args": 
+  {
+    "jobContainer": {
+      "image": "node:14.16",
+      "workingDirectory": "/__w/thboop-test2/thboop-test2",
+      "createOptions": "--cpus 1",
+      "environmentVariables": {
+        "NODE_ENV": "development"
+      },
+      "userMountVolumes:[
+        {
+          "sourceVolumePath": "my_docker_volume",
+          "targetVolumePath": "/volume_mount",
+          "readOnly": false
+        },
+      ],
+      "mountVolumes": [
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work",
+          "targetVolumePath": "/__w",
+          "readOnly": false
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/externals",
+          "targetVolumePath": "/__e",
+          "readOnly": true
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work/_temp",
+          "targetVolumePath": "/__w/_temp",
+          "readOnly": false
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work/_actions",
+          "targetVolumePath": "/__w/_actions",
+          "readOnly": false
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work/_tool",
+          "targetVolumePath": "/__w/_tool",
+          "readOnly": false
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work/_temp/_github_home",
+          "targetVolumePath": "/github/home",
+          "readOnly": false
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work/_temp/_github_workflow",
+          "targetVolumePath": "/github/workflow",
+          "readOnly": false
+        }
+      ],
+      "registry": {
+        "username": "foo",
+        "password": "bar",
+        "serverUrl": "https://index.docker.io/v1"
+      },
+      "portMappings": [ "8080:80/tcp", "8080:80/udp" ]
+    },
+    "services": [
+      {
+        "contextName": "redis",
+        "image": "redis",
+        "createOptions": "--cpus 1",
+        "environmentVariables": {},
+        "mountVolumes": [],
+        "portMappings": [ "8080:80/tcp", "8080:80/udp" ]
+        "registry": {
+          "username": "foo",
+          "password": "bar",
+          "serverUrl": "https://index.docker.io/v1"
+        }
+      }
+    ]
+  }
+}
+```
+
+</details>
+
+<details>
+<summary>Field Descriptions</summary>
+<br>
+
+```
+Arg Fields:
+
+jobContainer: **Optional** An Object containing information about the specified job container
+  "image": **Required** A string containing the docker image
+  "workingDirectory": **Required** A string containing the absolute path of the working directory
+  "createOptions": **Optional** The optional create options specified in the [YAML](https://docs.github.com/en/actions/using-jobs/running-jobs-in-a-container#example-running-a-job-within-a-container)
+  "environmentVariables": **Optional** A map of key value env's to set
+  "userMountVolumes: ** Optional** an array of user mount volumes set in the [YAML](https://docs.github.com/en/actions/using-jobs/running-jobs-in-a-container#example-running-a-job-within-a-container)
+    "sourceVolumePath": **Required** The source path to the volume to be mounted into the docker container
+    "targetVolumePath": **Required** The target path to the volume to be mounted into the docker container
+    "readOnly": false **Required** whether or not the mount should be read only
+  "mountVolumes": **Required** an array of mounts to mount into the container, same fields as above
+    "sourceVolumePath": **Required** The source path to the volume to be mounted into the docker container
+    "targetVolumePath": **Required** The target path to the volume to be mounted into the docker container
+    "readOnly": false **Required** whether or not the mount should be read only
+  "registry" **Optional** docker registry credentials to use when using a private container registry
+    "username": **Optional** the username
+    "password": **Optional** the password
+    "serverUrl": **Optional** the registry url
+  "portMappings": **Optional** an array of source:target ports to map into the container
+ 
+"services": an array of service containers to spin up
+  "contextName": **Required** the name of the service in the Job context
+  "image": **Required** A string containing the docker image
+  "createOptions": **Optional** The optional create options specified in the [YAML](https://docs.github.com/en/actions/using-jobs/running-jobs-in-a-container#example-running-a-job-within-a-container)
+  "environmentVariables": **Optional** A map of key value env's to set
+  "mountVolumes": **Required** an array of mounts to mount into the container, same fields as above
+    "sourceVolumePath": **Required** The source path to the volume to be mounted into the docker container
+    "targetVolumePath": **Required** The target path to the volume to be mounted into the docker container
+    "readOnly": false **Required** whether or not the mount should be read only
+  "registry" **Optional** docker registry credentials to use when using a private container registry
+    "username": **Optional** the username
+    "password": **Optional** the password
+    "serverUrl": **Optional** the registry url
+  "portMappings": **Optional** an array of source:target ports to map into the container
+```
+
+</details>
+
+<details>
+<summary>Example Output</summary>
+<br>
+
+```
+{
+  "state": 
+  {
+    "network": "github_network_53269bd575974817b43f4733536b200c",
+    "jobContainer" : "82e8219701fe096a35941d869cf8d71af1d943b5d3bdd718850fb87ac3042480",
+    "serviceContainers": 
+    {
+      "redis": "60972d9aa486605e66b0dad4abb638dc3d9116f566579e418166eedb8abb9105"
+    }
+  },
+  "context"
+  {
+    "container" : 
+    {
+      "id": "82e8219701fe096a35941d869cf8d71af1d943b5d3bdd718850fb87ac3042480"
+      "network": "github_network_53269bd575974817b43f4733536b200c"
+    }
+    "services": {
+      "redis": {
+        "id": "60972d9aa486605e66b0dad4abb638dc3d9116f566579e418166eedb8abb9105",
+        "ports": {
+          "8080": "8080"
+        },
+      "network": "github_network_53269bd575974817b43f4733536b200c"
+    }
+  }
+  "alpine: true,
+}
+```
+
+</details>
+
+
+### Cleanup Job
+The `cleanup_job` hook is called at the end of a job and expects you to:
+- Stop any running service or job containers (or the equiavalent pod)
+- Stop the network (if one exists)
+- Delete any job or service containers (or the equiavalent pod)
+- Delete the network (if one exists)
+- Cleanup anything else that was created for the run
+
+Its input looks like
+
+<details>
+<summary>Example Input</summary>
+<br>
+
+```
+  "command": "cleanup_job",
+  "responseFile": null,
+  "state":
+  {
+    "network": "github_network_53269bd575974817b43f4733536b200c",
+    "jobContainer" : "82e8219701fe096a35941d869cf8d71af1d943b5d3bdd718850fb87ac3042480",
+    "serviceContainers": 
+    {
+      "redis": "60972d9aa486605e66b0dad4abb638dc3d9116f566579e418166eedb8abb9105"
+    }
+  }
+  "args": {}
+```
+  
+</details>
+
+No args are provided.
+  
+No output is expected.
+
+
+### Run Container Step
+The `run_container_step` is called once per container action in your job and expects you to:
+- Pull or build the required container (or fail if you cannot)
+- Run the container action and return the exit code of the container
+- Stream any step logs output to stdout and stderr
+- Cleanup the container after it executes
+
+<details>
+<summary>Example Input for Image</summary>
+<br>
+
+```
+  "command": "run_container_step",
+  "responseFile": null,
+  "state":
+  {
+    "network": "github_network_53269bd575974817b43f4733536b200c",
+    "jobContainer" : "82e8219701fe096a35941d869cf8d71af1d943b5d3bdd718850fb87ac3042480",
+    "serviceContainers": 
+    {
+      "redis": "60972d9aa486605e66b0dad4abb638dc3d9116f566579e418166eedb8abb9105"
+    }
+  }
+  "args":      
+  {
+      "image": "node:14.16",
+      "dockerfile": null,
+      "entryPointArgs": ["-f", "/dev/null"],
+      "entryPoint": "tail",
+      "workingDirectory": "/__w/thboop-test2/thboop-test2",
+      "createOptions": "--cpus 1",
+      "environmentVariables": {
+        "NODE_ENV": "development"
+      },
+      "prependPath":["/foo/bar", "bar/foo"]
+      "userMountVolumes:[
+        {
+          "sourceVolumePath": "my_docker_volume",
+          "targetVolumePath": "/volume_mount",
+          "readOnly": false
+        },
+      ],
+      "mountVolumes": [
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work",
+          "targetVolumePath": "/__w",
+          "readOnly": false
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/externals",
+          "targetVolumePath": "/__e",
+          "readOnly": true
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work/_temp",
+          "targetVolumePath": "/__w/_temp",
+          "readOnly": false
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work/_actions",
+          "targetVolumePath": "/__w/_actions",
+          "readOnly": false
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work/_tool",
+          "targetVolumePath": "/__w/_tool",
+          "readOnly": false
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work/_temp/_github_home",
+          "targetVolumePath": "/github/home",
+          "readOnly": false
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work/_temp/_github_workflow",
+          "targetVolumePath": "/github/workflow",
+          "readOnly": false
+        }
+      ],
+      "registry": null,
+      "portMappings": { "80": "801" }
+    },
+```
+  
+</details>
+
+
+<details>
+<summary>Example Input for dockerfile</summary>
+<br>
+
+```
+  "command": "run_container_step",
+  "responseFile": null,
+  "state":
+  {
+    "network": "github_network_53269bd575974817b43f4733536b200c",
+    "jobContainer" : "82e8219701fe096a35941d869cf8d71af1d943b5d3bdd718850fb87ac3042480",
+    "services": 
+    {
+      "redis": "60972d9aa486605e66b0dad4abb638dc3d9116f566579e418166eedb8abb9105"
+    }
+  }
+  "args":      
+  {
+      "image": null,
+      "dockerfile": /__w/_actions/foo/dockerfile,
+      "entryPointArgs": ["hello world"],
+      "entryPoint": "echo",
+      "workingDirectory": "/__w/thboop-test2/thboop-test2",
+      "createOptions": "--cpus 1",
+      "environmentVariables": {
+        "NODE_ENV": "development"
+      },
+      "prependPath":["/foo/bar", "bar/foo"]
+      "userMountVolumes:[
+        {
+          "sourceVolumePath": "my_docker_volume",
+          "targetVolumePath": "/volume_mount",
+          "readOnly": false
+        },
+      ],      
+      "mountVolumes": [
+        {
+          "sourceVolumePath": "my_docker_volume",
+          "targetVolumePath": "/volume_mount",
+          "readOnly": false
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work",
+          "targetVolumePath": "/__w",
+          "readOnly": false
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/externals",
+          "targetVolumePath": "/__e",
+          "readOnly": true
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work/_temp",
+          "targetVolumePath": "/__w/_temp",
+          "readOnly": false
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work/_actions",
+          "targetVolumePath": "/__w/_actions",
+          "readOnly": false
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work/_tool",
+          "targetVolumePath": "/__w/_tool",
+          "readOnly": false
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work/_temp/_github_home",
+          "targetVolumePath": "/github/home",
+          "readOnly": false
+        },
+        {
+          "sourceVolumePath": "/home/thomas/git/runner/_layout/_work/_temp/_github_workflow",
+          "targetVolumePath": "/github/workflow",
+          "readOnly": false
+        }
+      ],
+      "registry": null,
+      "portMappings": [ "8080:80/tcp", "8080:80/udp" ]
+    },
+  }
+```
+  
+</details>
+
+
+<details>
+<summary>Field Descriptions</summary>
+<br>
+
+```
+Arg Fields:
+
+
+"image": **Optional** A string containing the docker image. Otherwise a dockerfile must be provided
+"dockerfile": **Optional** A string containing the path to the dockerfile, otherwise an image must be provided
+"entryPointArgs": **Optional** A list containing the entry point args
+"entryPoint": **Optional** The container entry point to use if the default image entrypoint should be overwritten
+"workingDirectory": **Required** A string containing the absolute path of the working directory
+"createOptions": **Optional** The optional create options specified in the [YAML](https://docs.github.com/en/actions/using-jobs/running-jobs-in-a-container#example-running-a-job-within-a-container)
+"environmentVariables": **Optional** A map of key value env's to set
+"prependPath": **Optional** an array of additional paths to prepend to the $PATH variable
+"userMountVolumes: ** Optional** an array of user mount volumes set in the [YAML](https://docs.github.com/en/actions/using-jobs/running-jobs-in-a-container#example-running-a-job-within-a-container)
+  "sourceVolumePath": **Required** The source path to the volume to be mounted into the docker container
+  "targetVolumePath": **Required** The target path to the volume to be mounted into the docker container
+  "readOnly": false **Required** whether or not the mount should be read only
+"mountVolumes": **Required** an array of mounts to mount into the container, same fields as above
+  "sourceVolumePath": **Required** The source path to the volume to be mounted into the docker container
+  "targetVolumePath": **Required** The target path to the volume to be mounted into the docker container
+  "readOnly": false **Required** whether or not the mount should be read only
+"registry" **Optional** docker registry credentials to use when using a private container registry
+  "username": **Optional** the username
+  "password": **Optional** the password
+  "serverUrl": **Optional** the registry url
+"portMappings": **Optional** an array of source:target ports to map into the container
+```
+  
+</details>
+
+No output is expected
+
+Currently we build all container actions at the start of the job. By doing it during the hook, we move this to just in time building for hooks. We could expose a hook to build/pull a container action, and have those called at the start of a job, but doing so would require hook authors to track the build containers in the state, which could be painful.
+
+### Run Script Step
+The `run_script_step` expects you to:
+- Invoke the provided script inside the job container and return the exit code
+- Stream any step log output to stdout and stderr
+
+<details>
+<summary>Example Input</summary>
+<br>
+
+
+```
+  "command": "run_script_step",
+  "responseFile": null,
+  "state":
+  {
+    "network": "github_network_53269bd575974817b43f4733536b200c",
+    "jobContainer" : "82e8219701fe096a35941d869cf8d71af1d943b5d3bdd718850fb87ac3042480",
+    "serviceContainers": 
+    {
+      "redis": "60972d9aa486605e66b0dad4abb638dc3d9116f566579e418166eedb8abb9105"
+    }
+  }
+  "args": 
+  {
+    "entryPointArgs": ["-e", "/runner/temp/abc123.sh"],
+    "entryPoint": "bash",
+    "environmentVariables": {
+      "NODE_ENV": "development"
+    },
+    "prependPath": ["/foo/bar", "bar/foo"],
+    "workingDirectory": "/__w/thboop-test2/thboop-test2"
+  }
+```
+  
+</details>
+
+<details>
+<summary>Field Descriptions</summary>
+<br>
+
+```
+Arg Fields:
+
+  
+"entryPointArgs": **Optional** A list containing the entry point args
+"entryPoint": **Optional** The container entry point to use if the default image entrypoint should be overwritten
+"prependPath": **Optional** an array of additional paths to prepend to the $PATH variable
+"workingDirectory": **Required** A string containing the absolute path of the working directory
+"environmentVariables": **Optional** A map of key value env's to set
+```
+
+</details>
+
+No output is expected
+
+
+## Limitations
+- We will only support linux on launch
+- Hooks are set by the runner admin, and thus are only supported on self hosted runners 
+
+## Consequences
+- We support non docker scenarios for self hosted runners and allow customers to customize their docker invocations
+- We ship/maintain docs on docker hooks and an open source repo with examples
+- We support these hooks and add enough telemetry to be able to troubleshoot support issues as they come in.

releaseNote.md

@@ -1,9 +1,7 @@
 ## Features
-- Added a pre-release package for the `macOS-arm64` architecture
-  - Note that this packages is pre-release status and may not work with all existing actions
-
 ## Bugs
-- Fixed an issue where live console logs would fail to close (#1903)
+- Fixed an issue where container environment variables names or values could escape the docker command (#2108)
+- Sanitize Windows ENVs (#2280)
 
 ## Misc
 

releaseVersion

@@ -1 +1 @@
-<Update to ./src/runnerversion when creating release>
+2.293.2

src/Runner.Common/Constants.cs

@@ -151,6 +151,7 @@ namespace GitHub.Runner.Common
                 public static readonly string DiskSpaceWarning = "runner.diskspace.warning";
                 public static readonly string Node12Warning = "DistributedTask.AddWarningToNode12Action";
                 public static readonly string UseContainerPathForTemplate = "DistributedTask.UseContainerPathForTemplate";
+                public static readonly string AllowRunnerContainerHooks = "DistributedTask.AllowRunnerContainerHooks"; 
             }
 
             public static readonly string InternalTelemetryIssueDataKey = "_internal_telemetry";
@@ -196,6 +197,7 @@ namespace GitHub.Runner.Common
         {
             public static readonly string JobStartedStepName = "Set up runner";
             public static readonly string JobCompletedStepName = "Complete runner";
+            public static readonly string ContainerHooksPath = "ACTIONS_RUNNER_CONTAINER_HOOKS";
         }
 
         public static class Path
@@ -227,6 +229,7 @@ namespace GitHub.Runner.Common
                 //
                 public static readonly string AllowUnsupportedCommands = "ACTIONS_ALLOW_UNSECURE_COMMANDS";
                 public static readonly string AllowUnsupportedStopCommandTokens = "ACTIONS_ALLOW_UNSECURE_STOPCOMMAND_TOKENS";
+                public static readonly string RequireJobContainer = "ACTIONS_RUNNER_REQUIRE_JOB_CONTAINER";
                 public static readonly string RunnerDebug = "ACTIONS_RUNNER_DEBUG";
                 public static readonly string StepDebug = "ACTIONS_STEP_DEBUG";
                 public static readonly string AllowActionsUseUnsecureNodeVersion = "ACTIONS_ALLOW_USE_UNSECURE_NODE_VERSION";

src/Runner.Common/HostContext.cs

@@ -13,6 +13,7 @@ using System.Runtime.Loader;
 using System.Threading;
 using System.Threading.Tasks;
 using GitHub.DistributedTask.Logging;
+using GitHub.Runner.Common.Util;
 using GitHub.Runner.Sdk;
 
 namespace GitHub.Runner.Common
@@ -641,6 +642,31 @@ namespace GitHub.Runner.Common
             var handlerFactory = context.GetService<IHttpClientHandlerFactory>();
             return handlerFactory.CreateClientHandler(context.WebProxy);
         }
+
+        public static string GetDefaultShellForScript(this IHostContext hostContext, string path, string prependPath)
+        {
+            var trace = hostContext.GetTrace(nameof(GetDefaultShellForScript));
+            switch (Path.GetExtension(path))
+            {
+                case ".sh":
+                    // use 'sh' args but prefer bash
+                    if (WhichUtil.Which("bash", false, trace, prependPath) != null)
+                    {
+                        return "bash";
+                    }
+                    return "sh";
+                case ".ps1":
+                    if (WhichUtil.Which("pwsh", false, trace, prependPath) != null)
+                    {
+                        return "pwsh";
+                    }
+                    return "powershell";
+                case ".js":
+                    return Path.Combine(hostContext.GetDirectory(WellKnownDirectory.Externals), NodeUtil.GetInternalNodeVersion(), "bin", $"node{IOUtil.ExeExtension}") + " {0}";
+                default:
+                    throw new ArgumentException($"{path} is not a valid path to a script. Make sure it ends in '.sh', '.ps1' or '.js'.");
+            }
+        }
     }
 
     public enum ShutdownReason

src/Runner.Common/RunServer.cs

@@ -0,0 +1,76 @@
+using System;
+using System.Collections.Generic;
+using System.Runtime.Serialization;
+using System.Threading;
+using System.Threading.Tasks;
+using GitHub.DistributedTask.Pipelines;
+using GitHub.DistributedTask.WebApi;
+using GitHub.Runner.Common.Util;
+using GitHub.Runner.Sdk;
+using GitHub.Services.Common;
+using GitHub.Services.WebApi;
+
+namespace GitHub.Runner.Common
+{
+    [ServiceLocator(Default = typeof(RunServer))]
+    public interface IRunServer : IRunnerService
+    {
+        Task ConnectAsync(Uri serverUrl, VssCredentials credentials);
+
+        Task<AgentJobRequestMessage> GetJobMessageAsync(string id);
+    }
+
+    public sealed class RunServer : RunnerService, IRunServer
+    {
+        private bool _hasConnection;
+        private VssConnection _connection;
+        private TaskAgentHttpClient _taskAgentClient;
+
+        public async Task ConnectAsync(Uri serverUrl, VssCredentials credentials)
+        {
+            _connection = await EstablishVssConnection(serverUrl, credentials, TimeSpan.FromSeconds(100));
+            _taskAgentClient = _connection.GetClient<TaskAgentHttpClient>();
+            _hasConnection = true;
+        }
+
+        private async Task<VssConnection> EstablishVssConnection(Uri serverUrl, VssCredentials credentials, TimeSpan timeout)
+        {
+            Trace.Info($"EstablishVssConnection");
+            Trace.Info($"Establish connection with {timeout.TotalSeconds} seconds timeout.");
+            int attemptCount = 5;
+            while (attemptCount-- > 0)
+            {
+                var connection = VssUtil.CreateConnection(serverUrl, credentials, timeout: timeout);
+                try
+                {
+                    await connection.ConnectAsync();
+                    return connection;
+                }
+                catch (Exception ex) when (attemptCount > 0)
+                {
+                    Trace.Info($"Catch exception during connect. {attemptCount} attempt left.");
+                    Trace.Error(ex);
+
+                    await HostContext.Delay(TimeSpan.FromMilliseconds(100), CancellationToken.None);
+                }
+            }
+
+            // should never reach here.
+            throw new InvalidOperationException(nameof(EstablishVssConnection));
+        }
+
+        private void CheckConnection()
+        {
+            if (!_hasConnection)
+            {
+                throw new InvalidOperationException($"SetConnection");
+            }
+        }
+
+        public Task<AgentJobRequestMessage> GetJobMessageAsync(string id)
+        {
+            CheckConnection();
+            return _taskAgentClient.GetJobMessageAsync(id);
+        }
+    }
+}

src/Runner.Listener/Runner.cs

@@ -1,18 +1,18 @@
-using GitHub.DistributedTask.WebApi;
-using GitHub.Runner.Listener.Configuration;
 using System;
-using System.Threading;
-using System.Threading.Tasks;
-using GitHub.Services.WebApi;
-using Pipelines = GitHub.DistributedTask.Pipelines;
+using System.Collections.Generic;
 using System.IO;
+using System.Linq;
 using System.Reflection;
 using System.Runtime.CompilerServices;
+using System.Threading;
+using System.Threading.Tasks;
+using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Common;
-using GitHub.Runner.Sdk;
-using System.Linq;
 using GitHub.Runner.Listener.Check;
-using System.Collections.Generic;
+using GitHub.Runner.Listener.Configuration;
+using GitHub.Runner.Sdk;
+using GitHub.Services.WebApi;
+using Pipelines = GitHub.DistributedTask.Pipelines;
 
 namespace GitHub.Runner.Listener
 {
@@ -322,6 +322,7 @@ namespace GitHub.Runner.Listener
 
                 // Should we try to cleanup ephemeral runners
                 bool runOnceJobCompleted = false;
+                bool skipSessionDeletion = false;
                 try
                 {
                     var notification = HostContext.GetService<IJobNotification>();
@@ -457,6 +458,35 @@ namespace GitHub.Runner.Listener
                                     }
                                 }
                             }
+                            // Broker flow
+                            else if (string.Equals(message.MessageType, JobRequestMessageTypes.RunnerJobRequest, StringComparison.OrdinalIgnoreCase))
+                            {
+                                if (autoUpdateInProgress || runOnceJobReceived)
+                                {
+                                    skipMessageDeletion = true;
+                                    Trace.Info($"Skip message deletion for job request message '{message.MessageId}'.");
+                                }
+                                else
+                                {
+                                    var messageRef = StringUtil.ConvertFromJson<RunnerJobRequestRef>(message.Body);
+
+                                    // Create connection
+                                    var credMgr = HostContext.GetService<ICredentialManager>();
+                                    var creds = credMgr.LoadCredentials();
+
+                                    // todo: add retries https://github.com/github/actions-broker/issues/49
+                                    var runServer = HostContext.CreateService<IRunServer>();
+                                    await runServer.ConnectAsync(new Uri(settings.ServerUrl), creds);
+                                    var jobMessage = await runServer.GetJobMessageAsync(messageRef.RunnerRequestId);
+
+                                    jobDispatcher.Run(jobMessage, runOnce);
+                                    if (runOnce)
+                                    {
+                                        Trace.Info("One time used runner received job message.");
+                                        runOnceJobReceived = true;
+                                    }
+                                }
+                            }
                             else if (string.Equals(message.MessageType, JobCancelMessage.MessageType, StringComparison.OrdinalIgnoreCase))
                             {
                                 var cancelJobMessage = JsonUtility.FromString<JobCancelMessage>(message.Body);
@@ -468,6 +498,14 @@ namespace GitHub.Runner.Listener
                                     Trace.Info($"Skip message deletion for cancellation message '{message.MessageId}'.");
                                 }
                             }
+                            else if (string.Equals(message.MessageType, Pipelines.HostedRunnerShutdownMessage.MessageType, StringComparison.OrdinalIgnoreCase))
+                            {
+                                var HostedRunnerShutdownMessage = JsonUtility.FromString<Pipelines.HostedRunnerShutdownMessage>(message.Body);
+                                skipMessageDeletion = true;
+                                skipSessionDeletion = true;
+                                Trace.Info($"Service requests the hosted runner to shutdown. Reason: '{HostedRunnerShutdownMessage.Reason}'.");
+                                return Constants.Runner.ReturnCode.Success;
+                            }
                             else
                             {
                                 Trace.Error($"Received message {message.MessageId} with unsupported message type {message.MessageType}.");
@@ -501,6 +539,8 @@ namespace GitHub.Runner.Listener
                         await jobDispatcher.ShutdownAsync();
                     }
 
+                    if (!skipSessionDeletion)
+                    {
                         try
                         {
                             await _listener.DeleteSessionAsync();
@@ -511,6 +551,7 @@ namespace GitHub.Runner.Listener
                             // and the delete session call will ends up with 401.
                             Trace.Info($"Ignore any exception during DeleteSession for an ephemeral runner. {ex}");
                         }
+                    }
 
                     messageQueueLoopTokenSource.Dispose();
 

src/Runner.Listener/RunnerJobRequestRef.cs

@@ -0,0 +1,13 @@
+using System.Runtime.Serialization;
+
+namespace GitHub.Runner.Listener
+{
+    [DataContract]
+    public sealed class RunnerJobRequestRef
+    {
+        [DataMember(Name = "id")]
+        public string Id { get; set; }
+        [DataMember(Name = "runner_request_id")]
+        public string RunnerRequestId { get; set; }
+    }
+}

src/Runner.Sdk/ProcessInvoker.cs

@@ -264,7 +264,17 @@ namespace GitHub.Runner.Sdk
             {
                 foreach (KeyValuePair<string, string> kvp in environment)
                 {
+#if OS_WINDOWS
+                    string tempKey = String.IsNullOrWhiteSpace(kvp.Key) ? kvp.Key : kvp.Key.Split('\0')[0];
+                    string tempValue = String.IsNullOrWhiteSpace(kvp.Value) ? kvp.Value : kvp.Value.Split('\0')[0];
+                    if(!String.IsNullOrWhiteSpace(tempKey))
+                    {
+                         _proc.StartInfo.Environment[tempKey] = tempValue;
+                    }
+#else
                     _proc.StartInfo.Environment[kvp.Key] = kvp.Value;
+
+#endif
                 }
             }
 

src/Runner.Sdk/Util/IOUtil.cs

@@ -424,6 +424,12 @@ namespace GitHub.Runner.Sdk
             throw new NotSupportedException($"Unable to validate execute permissions for directory '{directory}'. Exceeded maximum iterations.");
         }
 
+        public static void CreateEmptyFile(string path)
+        {
+            Directory.CreateDirectory(Path.GetDirectoryName(path));
+            File.WriteAllText(path, null);
+        }
+
         /// <summary>
         /// Recursively enumerates a directory without following directory reparse points.
         /// </summary>

src/Runner.Sdk/Util/VssUtil.cs

@@ -57,6 +57,10 @@ namespace GitHub.Runner.Sdk
                 settings.SendTimeout = TimeSpan.FromSeconds(Math.Min(Math.Max(httpRequestTimeoutSeconds, 100), 1200));
             }
 
+            if (StringUtil.ConvertToBoolean(Environment.GetEnvironmentVariable("GITHUB_ACTIONS_RUNNER_ALLOW_REDIRECT")))
+            {
+                settings.AllowAutoRedirect = true;
+            }
 
             // Remove Invariant from the list of accepted languages.
             //

src/Runner.Sdk/Util/WhichUtil.cs

@@ -1,7 +1,6 @@
 using System;
 using System.IO;
 using System.Linq;
-using GitHub.Runner.Sdk;
 
 namespace GitHub.Runner.Sdk
 {

src/Runner.Worker/ActionManager.cs

@@ -101,6 +101,8 @@ namespace GitHub.Runner.Worker
             IEnumerable<Pipelines.ActionStep> actions = steps.OfType<Pipelines.ActionStep>();
             executionContext.Output("Prepare all required actions");
             var result = await PrepareActionsRecursiveAsync(executionContext, state, actions, depth, rootStepId);
+            if (!FeatureManager.IsContainerHooksEnabled(executionContext.Global.Variables))
+            {
                 if (state.ImagesToPull.Count > 0)
                 {
                     foreach (var imageToPull in result.ImagesToPull)
@@ -133,6 +135,7 @@ namespace GitHub.Runner.Worker
                     containerSetupSteps.Clear();
                 }
 #endif
+            }
             return new PrepareResult(containerSetupSteps, result.PreStepTracker);
         }
 

src/Runner.Worker/ActionRunner.cs

@@ -158,8 +158,12 @@ namespace GitHub.Runner.Worker
             // Setup container stephost for running inside the container.
             if (ExecutionContext.Global.Container != null)
             {
-                // Make sure required container is already created.
+                // Make sure the required container is already created
+                // Container hooks do not necessarily set 'ContainerId'
+                if (!FeatureManager.IsContainerHooksEnabled(ExecutionContext.Global.Variables))
+                {
                     ArgUtil.NotNullOrEmpty(ExecutionContext.Global.Container.ContainerId, nameof(ExecutionContext.Global.Container.ContainerId));
+                }
                 var containerStepHost = HostContext.CreateService<IContainerStepHost>();
                 containerStepHost.Container = ExecutionContext.Global.Container;
                 stepHost = containerStepHost;

src/Runner.Worker/Container/ContainerHooks/ContainerHookManager.cs

@@ -0,0 +1,280 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Threading.Tasks;
+using GitHub.DistributedTask.Pipelines.ContextData;
+using GitHub.DistributedTask.WebApi;
+using GitHub.Runner.Common;
+using GitHub.Runner.Common.Util;
+using GitHub.Runner.Sdk;
+using GitHub.Runner.Worker.Handlers;
+using GitHub.Services.WebApi;
+using Newtonsoft.Json.Linq;
+
+namespace GitHub.Runner.Worker.Container.ContainerHooks
+{
+    [ServiceLocator(Default = typeof(ContainerHookManager))]
+    public interface IContainerHookManager : IRunnerService
+    {
+        Task PrepareJobAsync(IExecutionContext context, List<ContainerInfo> containers);
+        Task RunContainerStepAsync(IExecutionContext context, ContainerInfo container, string dockerFile);
+        Task RunScriptStepAsync(IExecutionContext context, ContainerInfo container, string workingDirectory, string fileName, string arguments, IDictionary<string, string> environment, string prependPath);
+        Task CleanupJobAsync(IExecutionContext context, List<ContainerInfo> containers);
+        string GetContainerHookData();
+    }
+
+    public class ContainerHookManager : RunnerService, IContainerHookManager
+    {
+        private const string ResponseFolderName = "_runner_hook_responses";
+        private string HookScriptPath;
+
+        public override void Initialize(IHostContext hostContext)
+        {
+            base.Initialize(hostContext);
+            HookScriptPath = $"{Environment.GetEnvironmentVariable(Constants.Hooks.ContainerHooksPath)}";
+        }
+
+        public async Task PrepareJobAsync(IExecutionContext context, List<ContainerInfo> containers)
+        {
+            Trace.Entering();
+            var jobContainer = containers.Where(c => c.IsJobContainer).SingleOrDefault();
+            var serviceContainers = containers.Where(c => !c.IsJobContainer).ToList();
+
+            var input = new HookInput
+            {
+                Command = HookCommand.PrepareJob,
+                ResponseFile = GenerateResponsePath(),
+                Args = new PrepareJobArgs
+                {
+                    Container = jobContainer?.GetHookContainer(),
+                    Services = serviceContainers.Select(c => c.GetHookContainer()).ToList(),
+                }
+            };
+
+            var prependPath = GetPrependPath(context);
+            var response = await ExecuteHookScript<PrepareJobResponse>(context, input, ActionRunStage.Pre, prependPath);
+            if (jobContainer != null)
+            {
+                jobContainer.IsAlpine = response.IsAlpine.Value;
+            }
+            SaveHookState(context, response.State, input);
+            UpdateJobContext(context, jobContainer, serviceContainers, response);
+        }
+
+        public async Task RunContainerStepAsync(IExecutionContext context, ContainerInfo container, string dockerFile)
+        {
+            Trace.Entering();
+            var hookState = context.Global.ContainerHookState;
+            var containerStepArgs = new ContainerStepArgs(container);
+            if (!string.IsNullOrEmpty(dockerFile))
+            {
+                containerStepArgs.Dockerfile = dockerFile;
+                containerStepArgs.Image = null;
+            }
+            var input = new HookInput
+            {
+                Args = containerStepArgs,
+                Command = HookCommand.RunContainerStep,
+                ResponseFile = GenerateResponsePath(),
+                State = hookState
+            };
+
+            var prependPath = GetPrependPath(context);
+            var response = await ExecuteHookScript<HookResponse>(context, input, ActionRunStage.Pre, prependPath);
+            if (response == null)
+            {
+                return;
+            }
+            SaveHookState(context, response.State, input);
+        }
+
+        public async Task RunScriptStepAsync(IExecutionContext context, ContainerInfo container, string workingDirectory, string entryPoint, string entryPointArgs, IDictionary<string, string> environmentVariables, string prependPath)
+        {
+            Trace.Entering();
+            var input = new HookInput
+            {
+                Command = HookCommand.RunScriptStep,
+                ResponseFile = GenerateResponsePath(),
+                Args = new ScriptStepArgs
+                {
+                    EntryPointArgs = entryPointArgs.Split(' ').Select(arg => arg.Trim()),
+                    EntryPoint = entryPoint,
+                    EnvironmentVariables = environmentVariables,
+                    PrependPath = prependPath,
+                    WorkingDirectory = workingDirectory,
+                },
+                State = context.Global.ContainerHookState
+            };
+
+            var response = await ExecuteHookScript<HookResponse>(context, input, ActionRunStage.Pre, prependPath);
+
+            if (response == null)
+            {
+                return;
+            }
+            SaveHookState(context, response.State, input);
+        }
+
+        public async Task CleanupJobAsync(IExecutionContext context, List<ContainerInfo> containers)
+        {
+            Trace.Entering();
+            var input = new HookInput
+            {
+                Command = HookCommand.CleanupJob,
+                ResponseFile = GenerateResponsePath(),
+                Args = new CleanupJobArgs(),
+                State = context.Global.ContainerHookState
+            };
+            var prependPath = GetPrependPath(context);
+            await ExecuteHookScript<HookResponse>(context, input, ActionRunStage.Pre, prependPath);
+        }
+
+        public string GetContainerHookData()
+        {
+            return JsonUtility.ToString(new { HookScriptPath });
+        }
+
+        private async Task<T> ExecuteHookScript<T>(IExecutionContext context, HookInput input, ActionRunStage stage, string prependPath) where T : HookResponse
+        {
+            try
+            {
+                ValidateHookExecutable();
+                context.StepTelemetry.ContainerHookData = GetContainerHookData();
+                var scriptDirectory = Path.GetDirectoryName(HookScriptPath);
+                var stepHost = HostContext.CreateService<IDefaultStepHost>();
+
+                Dictionary<string, string> inputs = new()
+                {
+                    ["standardInInput"] = JsonUtility.ToString(input),
+                    ["path"] = HookScriptPath,
+                    ["shell"] = HostContext.GetDefaultShellForScript(HookScriptPath, prependPath)
+                };
+                var handlerFactory = HostContext.GetService<IHandlerFactory>();
+                var handler = handlerFactory.Create(
+                                context,
+                                null,
+                                stepHost,
+                                new ScriptActionExecutionData(),
+                                inputs,
+                                environment: new Dictionary<string, string>(VarUtil.EnvironmentVariableKeyComparer),
+                                context.Global.Variables,
+                                actionDirectory: scriptDirectory,
+                                localActionContainerSetupSteps: null) as ScriptHandler;
+                handler.PrepareExecution(stage);
+
+                IOUtil.CreateEmptyFile(input.ResponseFile);
+                await handler.RunAsync(stage);
+                if (handler.ExecutionContext.Result == TaskResult.Failed)
+                {
+                    throw new Exception($"The hook script at '{HookScriptPath}' running command '{input.Command}' did not execute successfully");
+                }
+                var response = GetResponse<T>(input);
+                return response;
+            }
+            catch (Exception ex)
+            {
+                Trace.Error(ex);
+                throw new Exception($"Custom container implementation failed with error: {ex.Message} Please contact your self hosted runner administrator.", ex);
+            }
+        }
+
+        private string GenerateResponsePath() => Path.Combine(HostContext.GetDirectory(WellKnownDirectory.Temp), ResponseFolderName, $"{Guid.NewGuid()}.json");
+
+        private static string GetPrependPath(IExecutionContext context) => string.Join(Path.PathSeparator.ToString(), context.Global.PrependPath.Reverse<string>());
+
+        private void ValidateHookExecutable()
+        {
+            if (!string.IsNullOrEmpty(HookScriptPath) && !File.Exists(HookScriptPath))
+            {
+                throw new FileNotFoundException($"File not found at '{HookScriptPath}'. Set {Constants.Hooks.ContainerHooksPath} to the path of an existing file.");
+            }
+
+            var supportedHookExtensions = new string[] { ".js", ".sh", ".ps1" };
+            if (!supportedHookExtensions.Any(extension => HookScriptPath.EndsWith(extension)))
+            {
+                throw new ArgumentOutOfRangeException($"Invalid file extension at '{HookScriptPath}'. {Constants.Hooks.ContainerHooksPath} must be a path to a file with one of the following extensions: {string.Join(", ", supportedHookExtensions)}");
+            }
+        }
+
+        private T GetResponse<T>(HookInput input) where T : HookResponse
+        {
+            if (!File.Exists(input.ResponseFile))
+            {
+                Trace.Info($"Response file for the hook script at '{HookScriptPath}' running command '{input.Command}' not found.");
+                if (input.Args.IsRequireAlpineInResponse())
+                {
+                    throw new Exception($"Response file is required but not found for the hook script at '{HookScriptPath}' running command '{input.Command}'");
+                }
+                return null;
+            }
+
+            T response = IOUtil.LoadObject<T>(input.ResponseFile);
+            Trace.Info($"Response file for the hook script at '{HookScriptPath}' running command '{input.Command}' was processed successfully");
+            IOUtil.DeleteFile(input.ResponseFile);
+            Trace.Info($"Response file for the hook script at '{HookScriptPath}' running command '{input.Command}' was deleted successfully");
+            if (response == null && input.Args.IsRequireAlpineInResponse())
+            {
+                throw new Exception($"Response file could not be read at '{HookScriptPath}' running command '{input.Command}'");
+            }
+            response?.Validate(input);
+            return response;
+        }
+
+        private void SaveHookState(IExecutionContext context, JObject hookState, HookInput input)
+        {
+            if (hookState == null)
+            {
+                Trace.Info($"No 'state' property found in response file for '{input.Command}'. Global variable for 'ContainerHookState' will not be updated.");
+                return;
+            }
+            context.Global.ContainerHookState = hookState;
+            Trace.Info($"Global variable 'ContainerHookState' updated successfully for '{input.Command}' with data found in 'state' property of the response file.");
+        }
+
+        private void UpdateJobContext(IExecutionContext context, ContainerInfo jobContainer, List<ContainerInfo> serviceContainers, PrepareJobResponse response)
+        {
+            if (response.Context == null)
+            {
+                Trace.Info($"The response file does not contain a context. The fields 'jobContext.Container' and 'jobContext.Services' will not be set.");
+                return;
+            }
+
+            var containerId = response.Context.Container?.Id;
+            if (containerId != null)
+            {
+                context.JobContext.Container["id"] = new StringContextData(containerId);
+                jobContainer.ContainerId = containerId;
+            }
+
+            var containerNetwork = response.Context.Container?.Network;
+            if (containerNetwork != null)
+            {
+                context.JobContext.Container["network"] = new StringContextData(containerNetwork);
+                jobContainer.ContainerNetwork = containerNetwork;
+            }
+
+            for (var i = 0; i < response.Context.Services.Count; i++)
+            {
+                var responseContainerInfo = response.Context.Services[i];
+                var globalContainerInfo = serviceContainers[i];
+                globalContainerInfo.ContainerId = responseContainerInfo.Id;
+                globalContainerInfo.ContainerNetwork = responseContainerInfo.Network;
+
+                var service = new DictionaryContextData()
+                {
+                    ["id"] = new StringContextData(responseContainerInfo.Id),
+                    ["ports"] = new DictionaryContextData(),
+                    ["network"] = new StringContextData(responseContainerInfo.Network)
+                };
+
+                globalContainerInfo.AddPortMappings(responseContainerInfo.Ports);
+                foreach (var portMapping in responseContainerInfo.Ports)
+                {
+                    (service["ports"] as DictionaryContextData)[portMapping.Key] = new StringContextData(portMapping.Value);
+                }
+                context.JobContext.Services[globalContainerInfo.ContainerNetworkAlias] = service;
+            }
+        }
+    }
+}

src/Runner.Worker/Container/ContainerHooks/HookInput.cs

@@ -0,0 +1,113 @@
+using System.Collections.Generic;
+using System.Runtime.Serialization;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Converters;
+using Newtonsoft.Json.Linq;
+using System.Linq;
+
+namespace GitHub.Runner.Worker.Container.ContainerHooks
+{
+    public class HookInput
+    {
+        public HookCommand Command { get; set; }
+        public string ResponseFile { get; set; }
+        public IHookArgs Args { get; set; }
+        public JObject State { get; set; }
+    }
+
+    [JsonConverter(typeof(StringEnumConverter))]
+    public enum HookCommand
+    {
+        [EnumMember(Value = "prepare_job")]
+        PrepareJob,
+        [EnumMember(Value = "cleanup_job")]
+        CleanupJob,
+        [EnumMember(Value = "run_script_step")]
+        RunScriptStep,
+        [EnumMember(Value = "run_container_step")]
+        RunContainerStep,
+    }
+    public interface IHookArgs
+    {
+        bool IsRequireAlpineInResponse();
+    }
+
+    public class PrepareJobArgs : IHookArgs
+    {
+        public HookContainer Container { get; set; }
+        public IList<HookContainer> Services { get; set; }
+        public bool IsRequireAlpineInResponse() => Container != null;
+    }
+
+    public class ScriptStepArgs : IHookArgs
+    {
+        public IEnumerable<string> EntryPointArgs { get; set; }
+        public string EntryPoint { get; set; }
+        public IDictionary<string, string> EnvironmentVariables { get; set; }
+        public string PrependPath { get; set; }
+        public string WorkingDirectory { get; set; }
+        public bool IsRequireAlpineInResponse() => false;
+    }
+
+    public class ContainerStepArgs : HookContainer, IHookArgs
+    {
+        public bool IsRequireAlpineInResponse() => false;
+        public ContainerStepArgs(ContainerInfo container) : base(container) { }
+    }
+    public class CleanupJobArgs : IHookArgs
+    {
+        public bool IsRequireAlpineInResponse() => false;
+    }
+
+    public class ContainerRegistry
+    {
+        public string Username { get; set; }
+        public string Password { get; set; }
+        public string ServerUrl { get; set; }
+    }
+
+    public class HookContainer
+    {
+        public string Image { get; set; }
+        public string Dockerfile { get; set; }
+        public IEnumerable<string> EntryPointArgs { get; set; } = new List<string>();
+        public string EntryPoint { get; set; }
+        public string WorkingDirectory { get; set; }
+        public string CreateOptions { get; private set; }
+        public ContainerRegistry Registry { get; set; }
+        public IDictionary<string, string> EnvironmentVariables { get; set; } = new Dictionary<string, string>();
+        public IEnumerable<string> PortMappings { get; set; } = new List<string>();
+        public IEnumerable<MountVolume> SystemMountVolumes { get; set; } = new List<MountVolume>();
+        public IEnumerable<MountVolume> UserMountVolumes { get; set; } = new List<MountVolume>();
+        public HookContainer() { } // For Json deserializer
+        public HookContainer(ContainerInfo container)
+        {
+            Image = container.ContainerImage;
+            EntryPointArgs = container.ContainerEntryPointArgs?.Split(' ').Select(arg => arg.Trim()) ?? new List<string>();
+            EntryPoint = container.ContainerEntryPoint;
+            WorkingDirectory = container.ContainerWorkDirectory;
+            CreateOptions = container.ContainerCreateOptions;
+            if (!string.IsNullOrEmpty(container.RegistryAuthUsername))
+            {
+                Registry = new ContainerRegistry
+                {
+                    Username = container.RegistryAuthUsername,
+                    Password = container.RegistryAuthPassword,
+                    ServerUrl = container.RegistryServer,
+                };
+            }
+            EnvironmentVariables = container.ContainerEnvironmentVariables;
+            PortMappings = container.UserPortMappings.Select(p => p.Value).ToList();
+            SystemMountVolumes = container.SystemMountVolumes;
+            UserMountVolumes = container.UserMountVolumes;
+        }
+    }
+
+    public static class ContainerInfoExtensions
+    {
+        public static HookContainer GetHookContainer(this ContainerInfo containerInfo)
+        {
+            return new HookContainer(containerInfo);
+        }
+    }
+}

src/Runner.Worker/Container/ContainerHooks/HookResponse.cs

@@ -0,0 +1,37 @@
+using System;
+using System.Collections.Generic;
+using Newtonsoft.Json.Linq;
+
+namespace GitHub.Runner.Worker.Container.ContainerHooks
+{
+    public class HookResponse
+    {
+        public JObject State { get; set; }
+        public virtual void Validate(HookInput input) { }
+    }
+    public class PrepareJobResponse : HookResponse
+    {
+        public ResponseContext Context { get; set; }
+        public bool? IsAlpine { get; set; }
+
+        public override void Validate(HookInput input)
+        {
+            bool hasJobContainer = ((PrepareJobArgs)input.Args).Container != null;
+            if (hasJobContainer && IsAlpine == null)
+            {
+                throw new Exception("The property 'isAlpine' is required but was not found in the response file.");
+            }
+        }
+    }
+    public class ResponseContext
+    {
+        public ResponseContainer Container { get; set; }
+        public IList<ResponseContainer> Services { get; set; } = new List<ResponseContainer>();
+    }
+    public class ResponseContainer
+    {
+        public string Id { get; set; }
+        public string Network { get; set; }
+        public IDictionary<string, string> Ports { get; set; }
+    }
+}

src/Runner.Worker/Container/ContainerInfo.cs

@@ -90,6 +90,7 @@ namespace GitHub.Runner.Worker.Container
         public string RegistryAuthUsername { get; set; }
         public string RegistryAuthPassword { get; set; }
         public bool IsJobContainer { get; set; }
+        public bool IsAlpine { get; set; }
 
         public IDictionary<string, string> ContainerEnvironmentVariables
         {
@@ -232,6 +233,14 @@ namespace GitHub.Runner.Worker.Container
             }
         }
 
+        public void AddPortMappings(IDictionary<string, string> portMappings)
+        {
+            foreach (var pair in portMappings)
+            {
+                PortMappings.Add(new PortMapping(pair.Key, pair.Value));
+            }
+        }
+
         public void AddPathTranslateMapping(string hostCommonPath, string containerCommonPath)
         {
             _pathMappings.Insert(0, new PathMapping(hostCommonPath, containerCommonPath));
@@ -322,6 +331,12 @@ namespace GitHub.Runner.Worker.Container
 
     public class PortMapping
     {
+        public PortMapping(string hostPort, string containerPort)
+        {
+            this.HostPort = hostPort;
+            this.ContainerPort = containerPort;
+        }
+
         public PortMapping(string hostPort, string containerPort, string protocol)
         {
             this.HostPort = hostPort;

src/Runner.Worker/Container/DockerCommandManager.cs

@@ -131,11 +131,11 @@ namespace GitHub.Runner.Worker.Container
             {
                 if (String.IsNullOrEmpty(env.Value))
                 {
-                    dockerOptions.Add($"-e \"{env.Key}\"");
+                    dockerOptions.Add(DockerUtil.CreateEscapedOption("-e", env.Key));
                 }
                 else
                 {
-                    dockerOptions.Add($"-e \"{env.Key}={env.Value.Replace("\"", "\\\"")}\"");
+                    dockerOptions.Add(DockerUtil.CreateEscapedOption("-e", env.Key, env.Value));
                 }
             }
 
@@ -202,7 +202,7 @@ namespace GitHub.Runner.Worker.Container
             {
                 // e.g. -e MY_SECRET maps the value into the exec'ed process without exposing
                 // the value directly in the command
-                dockerOptions.Add($"-e {env.Key}");
+                dockerOptions.Add(DockerUtil.CreateEscapedOption("-e", env.Key));
             }
 
             // Watermark for GitHub Action environment

src/Runner.Worker/Container/DockerUtil.cs

@@ -6,6 +6,9 @@ namespace GitHub.Runner.Worker.Container
 {
     public class DockerUtil
     {
+        private static readonly Regex QuoteEscape = new Regex(@"(\\*)" + "\"", RegexOptions.Compiled);
+        private static readonly Regex EndOfStringEscape = new Regex(@"(\\+)$", RegexOptions.Compiled);
+
         public static List<PortMapping> ParseDockerPort(IList<string> portMappingLines)
         {
             const string targetPort = "targetPort";
@@ -61,5 +64,44 @@ namespace GitHub.Runner.Worker.Container
             }
             return "";
         }
+
+        public static string CreateEscapedOption(string flag, string key)
+        {
+            if (String.IsNullOrEmpty(key))
+            {
+                return "";
+            }
+            return $"{flag} {EscapeString(key)}";
+        }
+
+        public static string CreateEscapedOption(string flag, string key, string value)
+        {
+            if (String.IsNullOrEmpty(key))
+            {
+                return "";
+            }
+            var escapedString = EscapeString($"{key}={value}");
+            return $"{flag} {escapedString}";
+        }
+
+        private static string EscapeString(string value)
+        {
+            if (String.IsNullOrEmpty(value))
+            {
+                return "";
+            }
+            // Dotnet escaping rules are weird here, we can only escape \ if it precedes a "
+            // If a double quotation mark follows two or an even number of backslashes, each proceeding backslash pair is replaced with one backslash and the double quotation mark is removed.
+            // If a double quotation mark follows an odd number of backslashes, including just one, each preceding pair is replaced with one backslash and the remaining backslash is removed; however, in this case the double quotation mark is not removed.
+            // https://docs.microsoft.com/en-us/dotnet/api/system.environment.getcommandlineargs?redirectedfrom=MSDN&view=net-6.0#remarks
+
+            // First, find any \ followed by a " and double the number of \ + 1.
+             value = QuoteEscape.Replace(value, @"$1$1\" + "\"");
+            // Next, what if it ends in `\`, it would escape the end quote. So, we need to detect that at the end of the string and perform the same escape
+            // Luckily, we can just use the $ character with detects the end of string in regex
+            value = EndOfStringEscape.Replace(value, @"$1$1");
+            // Finally, wrap it in quotes
+            return $"\"{value}\"";
+        }
     }
 }

src/Runner.Worker/ContainerOperationProvider.cs

@@ -1,7 +1,6 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
-using System.ServiceProcess;
 using System.Threading.Tasks;
 using System.Linq;
 using System.Threading;
@@ -10,8 +9,12 @@ using GitHub.Services.Common;
 using GitHub.Runner.Common;
 using GitHub.Runner.Sdk;
 using GitHub.DistributedTask.Pipelines.ContextData;
-using Microsoft.Win32;
 using GitHub.DistributedTask.Pipelines.ObjectTemplating;
+using GitHub.Runner.Worker.Container.ContainerHooks;
+#if OS_WINDOWS // keep win specific imports around even through we don't support containers on win at the moment
+using System.ServiceProcess;
+using Microsoft.Win32;
+#endif
 
 namespace GitHub.Runner.Worker
 {
@@ -25,11 +28,13 @@ namespace GitHub.Runner.Worker
     public class ContainerOperationProvider : RunnerService, IContainerOperationProvider
     {
         private IDockerCommandManager _dockerManager;
+        private IContainerHookManager _containerHookManager;
 
         public override void Initialize(IHostContext hostContext)
         {
             base.Initialize(hostContext);
             _dockerManager = HostContext.GetService<IDockerCommandManager>();
+            _containerHookManager = HostContext.GetService<IContainerHookManager>();
         }
 
         public async Task StartContainersAsync(IExecutionContext executionContext, object data)
@@ -50,72 +55,15 @@ namespace GitHub.Runner.Worker
 
             executionContext.Debug($"Register post job cleanup for stopping/deleting containers.");
             executionContext.RegisterPostJobStep(postJobStep);
-
-            // Check whether we are inside a container.
-            // Our container feature requires to map working directory from host to the container.
-            // If we are already inside a container, we will not able to find out the real working direcotry path on the host.
-#if OS_WINDOWS
-#pragma warning disable CA1416
-            // service CExecSvc is Container Execution Agent.
-            ServiceController[] scServices = ServiceController.GetServices();
-            if (scServices.Any(x => String.Equals(x.ServiceName, "cexecsvc", StringComparison.OrdinalIgnoreCase) && x.Status == ServiceControllerStatus.Running))
+            if (FeatureManager.IsContainerHooksEnabled(executionContext.Global.Variables))
             {
-                throw new NotSupportedException("Container feature is not supported when runner is already running inside container.");
-            }
-#pragma warning restore CA1416
-#else
-            var initProcessCgroup = File.ReadLines("/proc/1/cgroup");
-            if (initProcessCgroup.Any(x => x.IndexOf(":/docker/", StringComparison.OrdinalIgnoreCase) >= 0))
-            {
-                throw new NotSupportedException("Container feature is not supported when runner is already running inside container.");
-            }
-#endif
-
-#if OS_WINDOWS
-#pragma warning disable CA1416
-            // Check OS version (Windows server 1803 is required)
-            object windowsInstallationType = Registry.GetValue(@"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion", "InstallationType", defaultValue: null);
-            ArgUtil.NotNull(windowsInstallationType, nameof(windowsInstallationType));
-            object windowsReleaseId = Registry.GetValue(@"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion", "ReleaseId", defaultValue: null);
-            ArgUtil.NotNull(windowsReleaseId, nameof(windowsReleaseId));
-            executionContext.Debug($"Current Windows version: '{windowsReleaseId} ({windowsInstallationType})'");
-
-            if (int.TryParse(windowsReleaseId.ToString(), out int releaseId))
-            {
-                if (!windowsInstallationType.ToString().StartsWith("Server", StringComparison.OrdinalIgnoreCase) || releaseId < 1803)
-                {
-                    throw new NotSupportedException("Container feature requires Windows Server 1803 or higher.");
-                }
-            }
-            else
-            {
-                throw new ArgumentOutOfRangeException(@"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ReleaseId");
-            }
-#pragma warning restore CA1416
-#endif
-
-            // Check docker client/server version
-            executionContext.Output("##[group]Checking docker version");
-            DockerVersion dockerVersion = await _dockerManager.DockerVersion(executionContext);
-            executionContext.Output("##[endgroup]");
-
-            ArgUtil.NotNull(dockerVersion.ServerVersion, nameof(dockerVersion.ServerVersion));
-            ArgUtil.NotNull(dockerVersion.ClientVersion, nameof(dockerVersion.ClientVersion));
-
-#if OS_WINDOWS
-            Version requiredDockerEngineAPIVersion = new Version(1, 30);  // Docker-EE version 17.6
-#else
-            Version requiredDockerEngineAPIVersion = new Version(1, 35); // Docker-CE version 17.12
-#endif
-
-            if (dockerVersion.ServerVersion < requiredDockerEngineAPIVersion)
-            {
-                throw new NotSupportedException($"Min required docker engine API server version is '{requiredDockerEngineAPIVersion}', your docker ('{_dockerManager.DockerPath}') server version is '{dockerVersion.ServerVersion}'");
-            }
-            if (dockerVersion.ClientVersion < requiredDockerEngineAPIVersion)
-            {
-                throw new NotSupportedException($"Min required docker engine API client version is '{requiredDockerEngineAPIVersion}', your docker ('{_dockerManager.DockerPath}') client version is '{dockerVersion.ClientVersion}'");
+                // Initialize the containers
+                containers.ForEach(container => UpdateRegistryAuthForGitHubToken(executionContext, container));
+                containers.Where(container => container.IsJobContainer).ForEach(container => MountWellKnownDirectories(executionContext, container));
+                await _containerHookManager.PrepareJobAsync(executionContext, containers);
+                return;
             }
+            await AssertCompatibleOS(executionContext);
 
             // Clean up containers left by previous runs
             executionContext.Output("##[group]Clean up resources from previous jobs");
@@ -166,6 +114,12 @@ namespace GitHub.Runner.Worker
             List<ContainerInfo> containers = data as List<ContainerInfo>;
             ArgUtil.NotNull(containers, nameof(containers));
 
+            if (FeatureManager.IsContainerHooksEnabled(executionContext.Global.Variables))
+            {
+                await _containerHookManager.CleanupJobAsync(executionContext, containers);
+                return;
+            }
+
             foreach (var container in containers)
             {
                 await StopContainerAsync(executionContext, container);
@@ -238,35 +192,7 @@ namespace GitHub.Runner.Worker
 
             if (container.IsJobContainer)
             {
-                // Configure job container - Mount workspace and tools, set up environment, and start long running process
-                var githubContext = executionContext.ExpressionValues["github"] as GitHubContext;
-                ArgUtil.NotNull(githubContext, nameof(githubContext));
-                var workingDirectory = githubContext["workspace"] as StringContextData;
-                ArgUtil.NotNullOrEmpty(workingDirectory, nameof(workingDirectory));
-                container.MountVolumes.Add(new MountVolume(HostContext.GetDirectory(WellKnownDirectory.Work), container.TranslateToContainerPath(HostContext.GetDirectory(WellKnownDirectory.Work))));
-#if OS_WINDOWS
-                container.MountVolumes.Add(new MountVolume(HostContext.GetDirectory(WellKnownDirectory.Externals), container.TranslateToContainerPath(HostContext.GetDirectory(WellKnownDirectory.Externals))));
-#else
-                container.MountVolumes.Add(new MountVolume(HostContext.GetDirectory(WellKnownDirectory.Externals), container.TranslateToContainerPath(HostContext.GetDirectory(WellKnownDirectory.Externals)), true));
-#endif
-                container.MountVolumes.Add(new MountVolume(HostContext.GetDirectory(WellKnownDirectory.Temp), container.TranslateToContainerPath(HostContext.GetDirectory(WellKnownDirectory.Temp))));
-                container.MountVolumes.Add(new MountVolume(HostContext.GetDirectory(WellKnownDirectory.Actions), container.TranslateToContainerPath(HostContext.GetDirectory(WellKnownDirectory.Actions))));
-                container.MountVolumes.Add(new MountVolume(HostContext.GetDirectory(WellKnownDirectory.Tools), container.TranslateToContainerPath(HostContext.GetDirectory(WellKnownDirectory.Tools))));
-
-                var tempHomeDirectory = Path.Combine(HostContext.GetDirectory(WellKnownDirectory.Temp), "_github_home");
-                Directory.CreateDirectory(tempHomeDirectory);
-                container.MountVolumes.Add(new MountVolume(tempHomeDirectory, "/github/home"));
-                container.AddPathTranslateMapping(tempHomeDirectory, "/github/home");
-                container.ContainerEnvironmentVariables["HOME"] = container.TranslateToContainerPath(tempHomeDirectory);
-
-                var tempWorkflowDirectory = Path.Combine(HostContext.GetDirectory(WellKnownDirectory.Temp), "_github_workflow");
-                Directory.CreateDirectory(tempWorkflowDirectory);
-                container.MountVolumes.Add(new MountVolume(tempWorkflowDirectory, "/github/workflow"));
-                container.AddPathTranslateMapping(tempWorkflowDirectory, "/github/workflow");
-
-                container.ContainerWorkDirectory = container.TranslateToContainerPath(workingDirectory);
-                container.ContainerEntryPoint = "tail";
-                container.ContainerEntryPointArgs = "\"-f\" \"/dev/null\"";
+                MountWellKnownDirectories(executionContext, container);
             }
 
             container.ContainerId = await _dockerManager.DockerCreate(executionContext, container);
@@ -329,6 +255,42 @@ namespace GitHub.Runner.Worker
             executionContext.Output("##[endgroup]");
         }
 
+        private void MountWellKnownDirectories(IExecutionContext executionContext, ContainerInfo container)
+        {
+            // Configure job container - Mount workspace and tools, set up environment, and start long running process
+            var githubContext = executionContext.ExpressionValues["github"] as GitHubContext;
+            ArgUtil.NotNull(githubContext, nameof(githubContext));
+            var workingDirectory = githubContext["workspace"] as StringContextData;
+            ArgUtil.NotNullOrEmpty(workingDirectory, nameof(workingDirectory));
+            container.MountVolumes.Add(new MountVolume(HostContext.GetDirectory(WellKnownDirectory.Work), container.TranslateToContainerPath(HostContext.GetDirectory(WellKnownDirectory.Work))));
+#if OS_WINDOWS
+                container.MountVolumes.Add(new MountVolume(HostContext.GetDirectory(WellKnownDirectory.Externals), container.TranslateToContainerPath(HostContext.GetDirectory(WellKnownDirectory.Externals))));
+#else
+            container.MountVolumes.Add(new MountVolume(HostContext.GetDirectory(WellKnownDirectory.Externals), container.TranslateToContainerPath(HostContext.GetDirectory(WellKnownDirectory.Externals)), true));
+#endif
+            container.MountVolumes.Add(new MountVolume(HostContext.GetDirectory(WellKnownDirectory.Temp), container.TranslateToContainerPath(HostContext.GetDirectory(WellKnownDirectory.Temp))));
+            container.MountVolumes.Add(new MountVolume(HostContext.GetDirectory(WellKnownDirectory.Actions), container.TranslateToContainerPath(HostContext.GetDirectory(WellKnownDirectory.Actions))));
+            container.MountVolumes.Add(new MountVolume(HostContext.GetDirectory(WellKnownDirectory.Tools), container.TranslateToContainerPath(HostContext.GetDirectory(WellKnownDirectory.Tools))));
+
+            var tempHomeDirectory = Path.Combine(HostContext.GetDirectory(WellKnownDirectory.Temp), "_github_home");
+            Directory.CreateDirectory(tempHomeDirectory);
+            container.MountVolumes.Add(new MountVolume(tempHomeDirectory, "/github/home"));
+            container.AddPathTranslateMapping(tempHomeDirectory, "/github/home");
+            container.ContainerEnvironmentVariables["HOME"] = container.TranslateToContainerPath(tempHomeDirectory);
+
+            var tempWorkflowDirectory = Path.Combine(HostContext.GetDirectory(WellKnownDirectory.Temp), "_github_workflow");
+            Directory.CreateDirectory(tempWorkflowDirectory);
+            container.MountVolumes.Add(new MountVolume(tempWorkflowDirectory, "/github/workflow"));
+            container.AddPathTranslateMapping(tempWorkflowDirectory, "/github/workflow");
+
+            container.ContainerWorkDirectory = container.TranslateToContainerPath(workingDirectory);
+            if (!FeatureManager.IsContainerHooksEnabled(executionContext.Global.Variables))
+            {
+                container.ContainerEntryPoint = "tail";
+                container.ContainerEntryPointArgs = "\"-f\" \"/dev/null\"";
+            }
+        }
+
         private async Task StopContainerAsync(IExecutionContext executionContext, ContainerInfo container)
         {
             Trace.Entering();
@@ -522,5 +484,74 @@ namespace GitHub.Runner.Worker
                 container.RegistryAuthPassword = executionContext.GetGitHubContext("token");
             }
         }
+
+        private async Task AssertCompatibleOS(IExecutionContext executionContext)
+        {
+            // Check whether we are inside a container.
+            // Our container feature requires to map working directory from host to the container.
+            // If we are already inside a container, we will not able to find out the real working direcotry path on the host.
+#if OS_WINDOWS
+#pragma warning disable CA1416
+            // service CExecSvc is Container Execution Agent.
+            ServiceController[] scServices = ServiceController.GetServices();
+            if (scServices.Any(x => String.Equals(x.ServiceName, "cexecsvc", StringComparison.OrdinalIgnoreCase) && x.Status == ServiceControllerStatus.Running))
+            {
+                throw new NotSupportedException("Container feature is not supported when runner is already running inside container.");
+            }
+#pragma warning restore CA1416
+#else
+            var initProcessCgroup = File.ReadLines("/proc/1/cgroup");
+            if (initProcessCgroup.Any(x => x.IndexOf(":/docker/", StringComparison.OrdinalIgnoreCase) >= 0))
+            {
+                throw new NotSupportedException("Container feature is not supported when runner is already running inside container.");
+            }
+#endif
+
+#if OS_WINDOWS
+#pragma warning disable CA1416
+            // Check OS version (Windows server 1803 is required)
+            object windowsInstallationType = Registry.GetValue(@"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion", "InstallationType", defaultValue: null);
+            ArgUtil.NotNull(windowsInstallationType, nameof(windowsInstallationType));
+            object windowsReleaseId = Registry.GetValue(@"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion", "ReleaseId", defaultValue: null);
+            ArgUtil.NotNull(windowsReleaseId, nameof(windowsReleaseId));
+            executionContext.Debug($"Current Windows version: '{windowsReleaseId} ({windowsInstallationType})'");
+
+            if (int.TryParse(windowsReleaseId.ToString(), out int releaseId))
+            {
+                if (!windowsInstallationType.ToString().StartsWith("Server", StringComparison.OrdinalIgnoreCase) || releaseId < 1803)
+                {
+                    throw new NotSupportedException("Container feature requires Windows Server 1803 or higher.");
+                }
+            }
+            else
+            {
+                throw new ArgumentOutOfRangeException(@"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ReleaseId");
+            }
+#pragma warning restore CA1416
+#endif
+
+            // Check docker client/server version
+            executionContext.Output("##[group]Checking docker version");
+            DockerVersion dockerVersion = await _dockerManager.DockerVersion(executionContext);
+            executionContext.Output("##[endgroup]");
+
+            ArgUtil.NotNull(dockerVersion.ServerVersion, nameof(dockerVersion.ServerVersion));
+            ArgUtil.NotNull(dockerVersion.ClientVersion, nameof(dockerVersion.ClientVersion));
+
+#if OS_WINDOWS
+            Version requiredDockerEngineAPIVersion = new Version(1, 30);  // Docker-EE version 17.6
+#else
+            Version requiredDockerEngineAPIVersion = new Version(1, 35); // Docker-CE version 17.12
+#endif
+
+            if (dockerVersion.ServerVersion < requiredDockerEngineAPIVersion)
+            {
+                throw new NotSupportedException($"Min required docker engine API server version is '{requiredDockerEngineAPIVersion}', your docker ('{_dockerManager.DockerPath}') server version is '{dockerVersion.ServerVersion}'");
+            }
+            if (dockerVersion.ClientVersion < requiredDockerEngineAPIVersion)
+            {
+                throw new NotSupportedException($"Min required docker engine API client version is '{requiredDockerEngineAPIVersion}', your docker ('{_dockerManager.DockerPath}') client version is '{dockerVersion.ClientVersion}'");
+            }
+        }
     }
 }

src/Runner.Worker/ExecutionContext.cs

@@ -1226,7 +1226,7 @@ namespace GitHub.Runner.Worker
                     var value = dict[key].ToString();
                     if (!string.IsNullOrEmpty(value))
                     {
-                        dict[key] = new StringContextData(stepHost.ResolvePathForStepHost(value));
+                        dict[key] = new StringContextData(stepHost.ResolvePathForStepHost(context, value));
                     }
                 }
                 else if (dict[key] is DictionaryContextData)

src/Runner.Worker/FeatureManager.cs

@@ -0,0 +1,15 @@
+using System;
+using GitHub.Runner.Common;
+
+namespace GitHub.Runner.Worker
+{
+    public class FeatureManager
+    {
+        public static bool IsContainerHooksEnabled(Variables variables)
+        {
+            var isContainerHookFeatureFlagSet = variables?.GetBoolean(Constants.Runner.Features.AllowRunnerContainerHooks) ?? false;
+            var isContainerHooksPathSet = !string.IsNullOrEmpty(Environment.GetEnvironmentVariable(Constants.Hooks.ContainerHooksPath));
+            return isContainerHookFeatureFlagSet && isContainerHooksPathSet;
+        }
+    }
+}

src/Runner.Worker/FileCommandManager.cs

@@ -275,12 +275,6 @@ namespace GitHub.Runner.Worker
 
         public void ProcessCommand(IExecutionContext context, string filePath, ContainerInfo container)
         {
-            if (!context.Global.Variables.GetBoolean("DistributedTask.UploadStepSummary") ?? true)
-            {
-                Trace.Info("Step Summary is disabled; skipping attachment upload");
-                return;
-            }
-
             if (String.IsNullOrEmpty(filePath) || !File.Exists(filePath))
             {
                 Trace.Info($"Step Summary file ({filePath}) does not exist; skipping attachment upload");

src/Runner.Worker/GlobalContext.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Common.Util;
 using GitHub.Runner.Worker.Container;
+using Newtonsoft.Json.Linq;
 
 namespace GitHub.Runner.Worker
 {
@@ -22,5 +23,6 @@ namespace GitHub.Runner.Worker
         public StepsContext StepsContext { get; set; }
         public Variables Variables { get; set; }
         public bool WriteDebug { get; set; }
+        public JObject ContainerHookState { get; set; }
     }
 }

src/Runner.Worker/Handlers/CompositeActionHandler.cs

@@ -11,6 +11,8 @@ using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Common;
 using GitHub.Runner.Common.Util;
 using GitHub.Runner.Sdk;
+using GitHub.Runner.Worker.Container;
+using GitHub.Runner.Worker.Container.ContainerHooks;
 using GitHub.Runner.Worker.Expressions;
 using Pipelines = GitHub.DistributedTask.Pipelines;
 

src/Runner.Worker/Handlers/ContainerActionHandler.cs

@@ -8,6 +8,7 @@ using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Common;
 using GitHub.Runner.Sdk;
 using GitHub.Runner.Worker.Container;
+using GitHub.Runner.Worker.Container.ContainerHooks;
 using Pipelines = GitHub.DistributedTask.Pipelines;
 
 namespace GitHub.Runner.Worker.Handlers
@@ -38,6 +39,8 @@ namespace GitHub.Runner.Worker.Handlers
             AddInputsToEnvironment();
 
             var dockerManager = HostContext.GetService<IDockerCommandManager>();
+            var containerHookManager = HostContext.GetService<IContainerHookManager>();
+            string dockerFile = null;
 
             // container image haven't built/pull
             if (Data.Image.StartsWith("docker://", StringComparison.OrdinalIgnoreCase))
@@ -47,9 +50,10 @@ namespace GitHub.Runner.Worker.Handlers
             else if (Data.Image.EndsWith("Dockerfile") || Data.Image.EndsWith("dockerfile"))
             {
                 // ensure docker file exist
-                var dockerFile = Path.Combine(ActionDirectory, Data.Image);
+                dockerFile = Path.Combine(ActionDirectory, Data.Image);
                 ArgUtil.File(dockerFile, nameof(Data.Image));
-
+                if (!FeatureManager.IsContainerHooksEnabled(ExecutionContext.Global.Variables))
+                {
                     ExecutionContext.Output($"##[group]Building docker image");
                     ExecutionContext.Output($"Dockerfile for action: '{dockerFile}'.");
                     var imageName = $"{dockerManager.DockerInstanceLabel}:{ExecutionContext.Id.ToString("N")}";
@@ -68,6 +72,7 @@ namespace GitHub.Runner.Worker.Handlers
 
                     Data.Image = imageName;
                 }
+            }
 
             string type = Action.Type == Pipelines.ActionSourceType.Repository ? "Dockerfile" : "DockerHub";
             // Set extra telemetry base on the current context.
@@ -220,6 +225,12 @@ namespace GitHub.Runner.Worker.Handlers
                 container.ContainerEnvironmentVariables[variable.Key] = container.TranslateToContainerPath(variable.Value);
             }
 
+            if (FeatureManager.IsContainerHooksEnabled(ExecutionContext.Global.Variables))
+            {
+                await containerHookManager.RunContainerStepAsync(ExecutionContext, container, dockerFile);
+            }
+            else
+            {
                 using (var stdoutManager = new OutputManager(ExecutionContext, ActionCommandManager, container))
                 using (var stderrManager = new OutputManager(ExecutionContext, ActionCommandManager, container))
                 {
@@ -230,6 +241,7 @@ namespace GitHub.Runner.Worker.Handlers
                         ExecutionContext.Result = TaskResult.Failed;
                     }
                 }
+            }
 #endif
         }
     }

src/Runner.Worker/Handlers/NodeScriptActionHandler.cs

@@ -8,6 +8,8 @@ using GitHub.DistributedTask.Pipelines.ContextData;
 using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Common;
 using GitHub.Runner.Sdk;
+using GitHub.Runner.Worker.Container;
+using GitHub.Runner.Worker.Container.ContainerHooks;
 
 namespace GitHub.Runner.Worker.Handlers
 {
@@ -109,7 +111,7 @@ namespace GitHub.Runner.Worker.Handlers
             // 1) Wrap the script file path in double quotes.
             // 2) Escape double quotes within the script file path. Double-quote is a valid
             // file name character on Linux.
-            string arguments = StepHost.ResolvePathForStepHost(StringUtil.Format(@"""{0}""", target.Replace(@"""", @"\""")));
+            string arguments = StepHost.ResolvePathForStepHost(ExecutionContext, StringUtil.Format(@"""{0}""", target.Replace(@"""", @"\""")));
 
 #if OS_WINDOWS
             // It appears that node.exe outputs UTF8 when not in TTY mode.
@@ -142,14 +144,16 @@ namespace GitHub.Runner.Worker.Handlers
                 // Execute the process. Exit code 0 should always be returned.
                 // A non-zero exit code indicates infrastructural failure.
                 // Task failure should be communicated over STDOUT using ## commands.
-                Task<int> step = StepHost.ExecuteAsync(workingDirectory: StepHost.ResolvePathForStepHost(workingDirectory),
-                                                fileName: StepHost.ResolvePathForStepHost(file),
+                Task<int> step = StepHost.ExecuteAsync(ExecutionContext,
+                                                workingDirectory: StepHost.ResolvePathForStepHost(ExecutionContext, workingDirectory),
+                                                fileName: StepHost.ResolvePathForStepHost(ExecutionContext, file),
                                                 arguments: arguments,
                                                 environment: Environment,
                                                 requireExitCodeZero: false,
                                                 outputEncoding: outputEncoding,
                                                 killProcessOnCancel: false,
                                                 inheritConsoleHandler: !ExecutionContext.Global.Variables.Retain_Default_Encoding,
+                                                standardInInput: null,
                                                 cancellationToken: ExecutionContext.CancellationToken);
 
                 // Wait for either the node exit or force finish through ##vso command

src/Runner.Worker/Handlers/ScriptHandler.cs

@@ -8,6 +8,8 @@ using GitHub.DistributedTask.WebApi;
 using GitHub.Runner.Common;
 using GitHub.Runner.Common.Util;
 using GitHub.Runner.Sdk;
+using GitHub.Runner.Worker.Container;
+using GitHub.Runner.Worker.Container.ContainerHooks;
 using Pipelines = GitHub.DistributedTask.Pipelines;
 
 namespace GitHub.Runner.Worker.Handlers
@@ -201,6 +203,23 @@ namespace GitHub.Runner.Worker.Handlers
                 argFormat = ScriptHandlerHelpers.GetScriptArgumentsFormat(shellCommand);
             }
             else
+            {
+                // For these shells, we want to use system binaries
+                var systemShells = new string[] { "bash", "sh", "powershell", "pwsh" };
+                if (!IsActionStep && systemShells.Contains(shell))
+                {
+                    shellCommand = shell;
+                    commandPath = WhichUtil.Which(shell, !isContainerStepHost, Trace, prependPath);
+                    if (shell == "bash")
+                    {
+                        argFormat = ScriptHandlerHelpers.GetScriptArgumentsFormat("sh");
+                    }
+                    else
+                    {
+                        argFormat = ScriptHandlerHelpers.GetScriptArgumentsFormat(shell);
+                    }
+                }
+                else
                 {
                     var parsed = ScriptHandlerHelpers.ParseShellOptionString(shell);
                     shellCommand = parsed.shellCommand;
@@ -212,6 +231,7 @@ namespace GitHub.Runner.Worker.Handlers
                         argFormat = ScriptHandlerHelpers.GetScriptArgumentsFormat(shellCommand);
                     }
                 }
+            }
 
             // Don't override runner telemetry here
             if (!string.IsNullOrEmpty(shellCommand) && IsActionStep)
@@ -229,7 +249,7 @@ namespace GitHub.Runner.Worker.Handlers
             {
                 // We do not not the full path until we know what shell is being used, so that we can determine the file extension
                 scriptFilePath = Path.Combine(tempDirectory, $"{Guid.NewGuid()}{ScriptHandlerHelpers.GetScriptFileExtension(shellCommand)}");
-                resolvedScriptPath = $"{StepHost.ResolvePathForStepHost(scriptFilePath).Replace("\"", "\\\"")}";
+                resolvedScriptPath = StepHost.ResolvePathForStepHost(ExecutionContext, scriptFilePath).Replace("\"", "\\\"");
             }
             else
             {
@@ -300,6 +320,7 @@ namespace GitHub.Runner.Worker.Handlers
 
             ExecutionContext.Debug($"{fileName} {arguments}");
 
+            Inputs.TryGetValue("standardInInput", out var standardInInput);
             using (var stdoutManager = new OutputManager(ExecutionContext, ActionCommandManager))
             using (var stderrManager = new OutputManager(ExecutionContext, ActionCommandManager))
             {
@@ -307,7 +328,8 @@ namespace GitHub.Runner.Worker.Handlers
                 StepHost.ErrorDataReceived += stderrManager.OnDataReceived;
 
                 // Execute
-                int exitCode = await StepHost.ExecuteAsync(workingDirectory: StepHost.ResolvePathForStepHost(workingDirectory),
+                int exitCode = await StepHost.ExecuteAsync(ExecutionContext,
+                                            workingDirectory: StepHost.ResolvePathForStepHost(ExecutionContext, workingDirectory),
                                             fileName: fileName,
                                             arguments: arguments,
                                             environment: Environment,
@@ -315,6 +337,7 @@ namespace GitHub.Runner.Worker.Handlers
                                             outputEncoding: null,
                                             killProcessOnCancel: false,
                                             inheritConsoleHandler: !ExecutionContext.Global.Variables.Retain_Default_Encoding,
+                                            standardInInput: standardInInput,
                                             cancellationToken: ExecutionContext.CancellationToken);
 
                 // Error

src/Runner.Worker/Handlers/ScriptHandlerHelpers.cs

@@ -3,10 +3,12 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using GitHub.Runner.Sdk;
+using GitHub.Runner.Common;
+using GitHub.Runner.Common.Util;
 
 namespace GitHub.Runner.Worker.Handlers
 {
-    internal class ScriptHandlerHelpers
+    internal static class ScriptHandlerHelpers
     {
         private static readonly Dictionary<string, string> _defaultArguments = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
         {
@@ -81,22 +83,5 @@ namespace GitHub.Runner.Worker.Handlers
                 throw new ArgumentException($"Failed to parse COMMAND [..ARGS] from {shellOption}");
             }
         }
-
-        internal static string GetDefaultShellForScript(string path, Common.Tracing trace, string prependPath)
-        {
-            var format = "{0} {1}";
-            switch (Path.GetExtension(path))
-            {
-                case ".sh":
-                    // use 'sh' args but prefer bash
-                    var pathToShell = WhichUtil.Which("bash", false, trace, prependPath) ?? WhichUtil.Which("sh", true, trace, prependPath);
-                    return string.Format(format, pathToShell, _defaultArguments["sh"]);
-                case ".ps1":
-                    var pathToPowershell = WhichUtil.Which("pwsh", false, trace, prependPath) ?? WhichUtil.Which("powershell", true, trace, prependPath);
-                    return string.Format(format, pathToPowershell, _defaultArguments["powershell"]);
-                default:
-                    throw new ArgumentException($"{path} is not a valid path to a script. Make sure it ends in '.sh' or '.ps1'.");
-            }
-        }
     }
 }

src/Runner.Worker/Handlers/StepHost.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using GitHub.DistributedTask.Pipelines.ContextData;
 using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
@@ -7,7 +8,9 @@ using GitHub.Runner.Worker.Container;
 using GitHub.Runner.Common;
 using GitHub.Runner.Sdk;
 using System.Linq;
-using GitHub.DistributedTask.Pipelines.ContextData;
+using GitHub.Runner.Worker.Container.ContainerHooks;
+using System.IO;
+using System.Threading.Channels;
 
 namespace GitHub.Runner.Worker.Handlers
 {
@@ -16,11 +19,12 @@ namespace GitHub.Runner.Worker.Handlers
         event EventHandler<ProcessDataReceivedEventArgs> OutputDataReceived;
         event EventHandler<ProcessDataReceivedEventArgs> ErrorDataReceived;
 
-        string ResolvePathForStepHost(string path);
+        string ResolvePathForStepHost(IExecutionContext executionContext, string path);
 
         Task<string> DetermineNodeRuntimeVersion(IExecutionContext executionContext, string preferredVersion);
 
-        Task<int> ExecuteAsync(string workingDirectory,
+        Task<int> ExecuteAsync(IExecutionContext context,
+                               string workingDirectory,
                                string fileName,
                                string arguments,
                                IDictionary<string, string> environment,
@@ -28,6 +32,7 @@ namespace GitHub.Runner.Worker.Handlers
                                Encoding outputEncoding,
                                bool killProcessOnCancel,
                                bool inheritConsoleHandler,
+                               string standardInInput,
                                CancellationToken cancellationToken);
     }
 
@@ -48,7 +53,7 @@ namespace GitHub.Runner.Worker.Handlers
         public event EventHandler<ProcessDataReceivedEventArgs> OutputDataReceived;
         public event EventHandler<ProcessDataReceivedEventArgs> ErrorDataReceived;
 
-        public string ResolvePathForStepHost(string path)
+        public string ResolvePathForStepHost(IExecutionContext executionContext, string path)
         {
             return path;
         }
@@ -58,7 +63,8 @@ namespace GitHub.Runner.Worker.Handlers
             return Task.FromResult<string>(preferredVersion);
         }
 
-        public async Task<int> ExecuteAsync(string workingDirectory,
+        public async Task<int> ExecuteAsync(IExecutionContext context,
+                                            string workingDirectory,
                                             string fileName,
                                             string arguments,
                                             IDictionary<string, string> environment,
@@ -66,10 +72,17 @@ namespace GitHub.Runner.Worker.Handlers
                                             Encoding outputEncoding,
                                             bool killProcessOnCancel,
                                             bool inheritConsoleHandler,
+                                            string standardInInput,
                                             CancellationToken cancellationToken)
         {
             using (var processInvoker = HostContext.CreateService<IProcessInvoker>())
             {
+                Channel<string> redirectStandardIn = null;
+                if (standardInInput != null)
+                {
+                    redirectStandardIn = Channel.CreateUnbounded<string>(new UnboundedChannelOptions() { SingleReader = true, SingleWriter = true });
+                    redirectStandardIn.Writer.TryWrite(standardInInput);
+                }
                 processInvoker.OutputDataReceived += OutputDataReceived;
                 processInvoker.ErrorDataReceived += ErrorDataReceived;
 
@@ -80,7 +93,7 @@ namespace GitHub.Runner.Worker.Handlers
                                                          requireExitCodeZero: requireExitCodeZero,
                                                          outputEncoding: outputEncoding,
                                                          killProcessOnCancel: killProcessOnCancel,
-                                                         redirectStandardIn: null,
+                                                         redirectStandardIn: redirectStandardIn,
                                                          inheritConsoleHandler: inheritConsoleHandler,
                                                          cancellationToken: cancellationToken);
             }
@@ -94,11 +107,15 @@ namespace GitHub.Runner.Worker.Handlers
         public event EventHandler<ProcessDataReceivedEventArgs> OutputDataReceived;
         public event EventHandler<ProcessDataReceivedEventArgs> ErrorDataReceived;
 
-        public string ResolvePathForStepHost(string path)
+        public string ResolvePathForStepHost(IExecutionContext executionContext, string path)
         {
             // make sure container exist.
             ArgUtil.NotNull(Container, nameof(Container));
+            if (!FeatureManager.IsContainerHooksEnabled(executionContext.Global?.Variables))
+            {
+                // TODO: Remove nullcheck with executionContext.Global? by setting up ExecutionContext.Global at GitHub.Runner.Common.Tests.Worker.ExecutionContextL0.GetExpressionValues_ContainerStepHost
                 ArgUtil.NotNullOrEmpty(Container.ContainerId, nameof(Container.ContainerId));
+            }
 
             // remove double quotes around the path
             path = path.Trim('\"');
@@ -120,6 +137,19 @@ namespace GitHub.Runner.Worker.Handlers
 
         public async Task<string> DetermineNodeRuntimeVersion(IExecutionContext executionContext, string preferredVersion)
         {
+            // Optimistically use the default
+            string nodeExternal = preferredVersion;
+
+            if (FeatureManager.IsContainerHooksEnabled(executionContext.Global.Variables))
+            {
+                if (Container.IsAlpine)
+                {
+                    nodeExternal = CheckPlatformForAlpineContainer(executionContext, preferredVersion);
+                }
+                executionContext.Debug($"Running JavaScript Action with default external tool: {nodeExternal}");
+                return nodeExternal;
+            }
+
             // Best effort to determine a compatible node runtime
             // There may be more variation in which libraries are linked than just musl/glibc,
             // so determine based on known distribtutions instead
@@ -128,7 +158,6 @@ namespace GitHub.Runner.Worker.Handlers
 
             var output = new List<string>();
             var execExitCode = await dockerManager.DockerExec(executionContext, Container.ContainerId, string.Empty, osReleaseIdCmd, output);
-            string nodeExternal;
             if (execExitCode == 0)
             {
                 foreach (var line in output)
@@ -136,26 +165,17 @@ namespace GitHub.Runner.Worker.Handlers
                     executionContext.Debug(line);
                     if (line.ToLower().Contains("alpine"))
                     {
-                        if (!Constants.Runner.PlatformArchitecture.Equals(Constants.Architecture.X64))
-                        {
-                            var os = Constants.Runner.Platform.ToString();
-                            var arch = Constants.Runner.PlatformArchitecture.ToString();
-                            var msg = $"JavaScript Actions in Alpine containers are only supported on x64 Linux runners. Detected {os} {arch}";
-                            throw new NotSupportedException(msg);
-                        }
-                        nodeExternal = $"{preferredVersion}_alpine";
-                        executionContext.Debug($"Container distribution is alpine. Running JavaScript Action with external tool: {nodeExternal}");
+                        nodeExternal = CheckPlatformForAlpineContainer(executionContext, preferredVersion);
                         return nodeExternal;
                     }
                 }
             }
-            // Optimistically use the default
-            nodeExternal = preferredVersion;
             executionContext.Debug($"Running JavaScript Action with default external tool: {nodeExternal}");
             return nodeExternal;
         }
 
-        public async Task<int> ExecuteAsync(string workingDirectory,
+        public async Task<int> ExecuteAsync(IExecutionContext context,
+                                            string workingDirectory,
                                             string fileName,
                                             string arguments,
                                             IDictionary<string, string> environment,
@@ -163,12 +183,25 @@ namespace GitHub.Runner.Worker.Handlers
                                             Encoding outputEncoding,
                                             bool killProcessOnCancel,
                                             bool inheritConsoleHandler,
+                                            string standardInInput,
                                             CancellationToken cancellationToken)
         {
-            // make sure container exist.
             ArgUtil.NotNull(Container, nameof(Container));
-            ArgUtil.NotNullOrEmpty(Container.ContainerId, nameof(Container.ContainerId));
+            var containerHookManager = HostContext.GetService<IContainerHookManager>();
+            if (FeatureManager.IsContainerHooksEnabled(context.Global.Variables))
+            {
+                TranslateToContainerPath(environment);
+                await containerHookManager.RunScriptStepAsync(context,
+                                                                                   Container,
+                                                                                   workingDirectory,
+                                                                                   fileName,
+                                                                                   arguments,
+                                                                                   environment,
+                                                                                   PrependPath);
+                return (int)(context.Result ?? 0);
+            }
 
+            ArgUtil.NotNullOrEmpty(Container.ContainerId, nameof(Container.ContainerId));
             var dockerManager = HostContext.GetService<IDockerCommandManager>();
             string dockerClientPath = dockerManager.DockerPath;
 
@@ -183,7 +216,7 @@ namespace GitHub.Runner.Worker.Handlers
             {
                 // e.g. -e MY_SECRET maps the value into the exec'ed process without exposing
                 // the value directly in the command
-                dockerCommandArgs.Add($"-e {env.Key}");
+                dockerCommandArgs.Add(DockerUtil.CreateEscapedOption("-e", env.Key));
             }
             if (!string.IsNullOrEmpty(PrependPath))
             {
@@ -202,12 +235,7 @@ namespace GitHub.Runner.Worker.Handlers
             dockerCommandArgs.Add(arguments);
 
             string dockerCommandArgstring = string.Join(" ", dockerCommandArgs);
-
-            // make sure all env are using container path
-            foreach (var envKey in environment.Keys.ToList())
-            {
-                environment[envKey] = this.Container.TranslateToContainerPath(environment[envKey]);
-            }
+            TranslateToContainerPath(environment);
 
             using (var processInvoker = HostContext.CreateService<IProcessInvoker>())
             {
@@ -221,7 +249,6 @@ namespace GitHub.Runner.Worker.Handlers
                 // Let .NET choose the default.
                 outputEncoding = null;
 #endif
-
                 return await processInvoker.ExecuteAsync(workingDirectory: HostContext.GetDirectory(WellKnownDirectory.Work),
                                                          fileName: dockerClientPath,
                                                          arguments: dockerCommandArgstring,
@@ -234,5 +261,28 @@ namespace GitHub.Runner.Worker.Handlers
                                                          cancellationToken: cancellationToken);
             }
         }
+
+        private string CheckPlatformForAlpineContainer(IExecutionContext executionContext, string preferredVersion)
+        {
+            string nodeExternal = preferredVersion;
+            if (!Constants.Runner.PlatformArchitecture.Equals(Constants.Architecture.X64))
+            {
+                var os = Constants.Runner.Platform.ToString();
+                var arch = Constants.Runner.PlatformArchitecture.ToString();
+                var msg = $"JavaScript Actions in Alpine containers are only supported on x64 Linux runners. Detected {os} {arch}";
+                throw new NotSupportedException(msg);
+            }
+            nodeExternal = $"{preferredVersion}_alpine";
+            executionContext.Debug($"Container distribution is alpine. Running JavaScript Action with external tool: {nodeExternal}");
+            return nodeExternal;
+        }
+
+        private void TranslateToContainerPath(IDictionary<string, string> environment)
+        {
+            foreach (var envKey in environment.Keys.ToList())
+            {
+                environment[envKey] = this.Container.TranslateToContainerPath(environment[envKey]);
+            }
+        }
     }
 }

src/Runner.Worker/JobExtension.cs

@@ -9,6 +9,7 @@ using System.Threading;
 using System.Threading.Tasks;
 using GitHub.DistributedTask.Expressions2;
 using GitHub.DistributedTask.ObjectTemplating.Tokens;
+using GitHub.DistributedTask.Pipelines;
 using GitHub.DistributedTask.Pipelines.ContextData;
 using GitHub.DistributedTask.Pipelines.ObjectTemplating;
 using GitHub.DistributedTask.WebApi;
@@ -206,6 +207,7 @@ namespace GitHub.Runner.Worker
                     // Evaluate the job container
                     context.Debug("Evaluating job container");
                     var container = templateEvaluator.EvaluateJobContainer(message.JobContainer, jobContext.ExpressionValues, jobContext.ExpressionFunctions);
+                    ValidateJobContainer(container);
                     if (container != null)
                     {
                         jobContext.Global.Container = new Container.ContainerInfo(HostContext, container);
@@ -672,5 +674,13 @@ namespace GitHub.Runner.Worker
             Trace.Info($"Total accessible running process: {snapshot.Count}.");
             return snapshot;
         }
+
+        private static void ValidateJobContainer(JobContainer container)
+        {
+            if (StringUtil.ConvertToBoolean(Environment.GetEnvironmentVariable(Constants.Variables.Actions.RequireJobContainer)) && container == null)
+            {
+                throw new ArgumentException("Jobs without a job container are forbidden on this runner, please add a 'container:' to your job or contact your self-hosted runner administrator.");
+            }
+        }
     }
 }

src/Runner.Worker/JobHookProvider.cs

@@ -60,7 +60,7 @@ namespace GitHub.Runner.Worker
             Dictionary<string, string> inputs = new()
             {
                 ["path"] = hookData.Path,
-                ["shell"] = ScriptHandlerHelpers.GetDefaultShellForScript(hookData.Path, Trace, prependPath)
+                ["shell"] = HostContext.GetDefaultShellForScript(hookData.Path, prependPath)
             };
 
             // Create the handler

src/Sdk/DTPipelines/Pipelines/RunnerShutdownMessage.cs

@@ -0,0 +1,39 @@
+using System;
+using System.Runtime.Serialization;
+using GitHub.Services.WebApi;
+using Newtonsoft.Json;
+
+namespace GitHub.DistributedTask.Pipelines
+{
+    [DataContract]
+    public sealed class HostedRunnerShutdownMessage
+    {
+        public static readonly String MessageType = "RunnerShutdown";
+
+        [JsonConstructor]
+        internal HostedRunnerShutdownMessage()
+        {
+        }
+
+        public HostedRunnerShutdownMessage(String reason)
+        {
+            this.Reason = reason;
+        }
+
+        [DataMember]
+        public String Reason
+        {
+            get;
+            private set;
+        }
+
+        public WebApi.TaskAgentMessage GetAgentMessage()
+        {
+            return new WebApi.TaskAgentMessage
+            {
+                Body = JsonUtility.ToString(this),
+                MessageType = HostedRunnerShutdownMessage.MessageType,
+            };
+        }
+    }
+}

src/Sdk/DTWebApi/WebApi/ActionsStepTelemetry.cs

@@ -56,5 +56,8 @@ namespace GitHub.DistributedTask.WebApi
 
         [DataMember(EmitDefaultValue = false)]
         public int? ExecutionTimeInSeconds { get; set; }
+
+        [DataMember(EmitDefaultValue = false)]
+        public string ContainerHookData { get; set; }
     }
 }

src/Sdk/DTWebApi/WebApi/JobRequestMessageTypes.cs

@@ -5,5 +5,6 @@ namespace GitHub.DistributedTask.WebApi
     public static class JobRequestMessageTypes
     {
         public const String PipelineAgentJobRequest = "PipelineAgentJobRequest";
+        public const String RunnerJobRequest = "RunnerJobRequest";
     }
 }

src/Sdk/DTWebApi/WebApi/TaskAgentHttpClient.cs

@@ -141,6 +141,24 @@ namespace GitHub.DistributedTask.WebApi
             return ReplaceAgentAsync(poolId, agent.Id, agent, userState, cancellationToken);
         }
 
+        public Task<Pipelines.AgentJobRequestMessage> GetJobMessageAsync(
+            string messageId,
+            object userState = null,
+            CancellationToken cancellationToken = default)
+        {
+            HttpMethod httpMethod = new HttpMethod("GET");
+            Guid locationId = new Guid("25adab70-1379-4186-be8e-b643061ebe3a");
+            object routeValues = new { messageId = messageId };
+
+            return SendAsync<Pipelines.AgentJobRequestMessage>(
+                httpMethod,
+                locationId,
+                routeValues: routeValues,
+                version: new ApiResourceVersion(6.0, 1),
+                userState: userState,
+                cancellationToken: cancellationToken);
+        }
+
         protected Task<T> SendAsync<T>(
             HttpMethod method,
             Guid locationId,

src/Test/L0/Container/DockerUtilL0.cs

@@ -144,5 +144,54 @@ namespace GitHub.Runner.Common.Tests.Worker.Container
             var actual = DockerUtil.ParseRegistryHostnameFromImageName(input);
             Assert.Equal(expected, actual);
         }
+
+        [Theory]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        [InlineData("", "")]
+        [InlineData("foo", "foo")]
+        [InlineData("foo \\ bar", "foo \\ bar")]
+        [InlineData("foo \\", "foo \\\\")]
+        [InlineData("foo \\\\", "foo \\\\\\\\")]
+        [InlineData("foo \\\" bar", "foo \\\\\\\" bar")]
+        [InlineData("foo \\\\\" bar", "foo \\\\\\\\\\\" bar")]
+        public void CreateEscapedOption_keyOnly(string input, string escaped)
+        {
+            var flag = "--example";
+            var actual = DockerUtil.CreateEscapedOption(flag, input);
+            string expected;
+            if (String.IsNullOrEmpty(input))
+            {
+                expected = "";
+            }
+            else
+            {
+                expected = $"{flag} \"{escaped}\"";
+            }
+            Assert.Equal(expected, actual);
+        }
+
+        [Theory]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        [InlineData("foo", "bar", "foo=bar")]
+        [InlineData("foo\\", "bar", "foo\\=bar")]
+        [InlineData("foo\\", "bar\\", "foo\\=bar\\\\")]
+        [InlineData("foo \\","bar \\", "foo \\=bar \\\\")]
+        public void CreateEscapedOption_keyValue(string keyInput, string valueInput, string escapedString)
+        {
+            var flag = "--example";
+            var actual = DockerUtil.CreateEscapedOption(flag, keyInput, valueInput);
+            string expected;
+            if (String.IsNullOrEmpty(keyInput))
+            {
+                expected = "";
+            }
+            else
+            {
+                expected = $"{flag} \"{escapedString}\"";
+            }
+            Assert.Equal(expected, actual);
+        }
     }
 }

src/Test/L0/ProcessInvokerL0.cs

@@ -129,7 +129,76 @@ namespace GitHub.Runner.Common.Tests
                 }
             }
         }
+#if OS_WINDOWS
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Common")]
+        public async Task SetTestEnvWithNullInKey()
+        {
+            using (TestHostContext hc = new(this))
+            {
+                Tracing trace = hc.GetTrace();
 
+                Int32 exitCode = -1;
+                var processInvoker = new ProcessInvokerWrapper();
+                processInvoker.Initialize(hc);
+                var stdout = new List<string>();
+                var stderr = new List<string>();
+                processInvoker.OutputDataReceived += (object sender, ProcessDataReceivedEventArgs e) =>
+                {
+                    trace.Info(e.Data);
+                    stdout.Add(e.Data);
+                };
+                processInvoker.ErrorDataReceived += (object sender, ProcessDataReceivedEventArgs e) =>
+                {
+                    trace.Info(e.Data);
+                    stderr.Add(e.Data);
+                };
+
+                exitCode = await processInvoker.ExecuteAsync("", "cmd.exe", "/c \"echo %TEST%\"",  new Dictionary<string, string>() { { "TEST\0second", "first" } }, CancellationToken.None);
+
+
+                trace.Info("Exit Code: {0}", exitCode);
+                Assert.Equal(0, exitCode);
+                Assert.Equal("first", stdout.First(x => !string.IsNullOrWhiteSpace(x)));
+
+            }
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Common")]
+        public async Task SetTestEnvWithNullInValue()
+        {
+            using (TestHostContext hc = new(this))
+            {
+                Tracing trace = hc.GetTrace();
+
+                Int32 exitCode = -1;
+                var processInvoker = new ProcessInvokerWrapper();
+                processInvoker.Initialize(hc);
+                var stdout = new List<string>();
+                var stderr = new List<string>();
+                processInvoker.OutputDataReceived += (object sender, ProcessDataReceivedEventArgs e) =>
+                {
+                    trace.Info(e.Data);
+                    stdout.Add(e.Data);
+                };
+                processInvoker.ErrorDataReceived += (object sender, ProcessDataReceivedEventArgs e) =>
+                {
+                    trace.Info(e.Data);
+                    stderr.Add(e.Data);
+                };
+
+                exitCode = await processInvoker.ExecuteAsync("", "cmd.exe", "/c \"echo %TEST%\"",  new Dictionary<string, string>() { { "TEST", "first\0second" } }, CancellationToken.None);
+
+                trace.Info("Exit Code: {0}", exitCode);
+                Assert.Equal(0, exitCode);
+                Assert.Equal("first", stdout.First(x => !string.IsNullOrWhiteSpace(x)));
+
+            }
+        }
+#endif
         [Fact]
         [Trait("Level", "L0")]
         [Trait("Category", "Common")]

src/Test/L0/ServiceInterfacesL0.cs

@@ -2,6 +2,7 @@
 using GitHub.Runner.Listener.Check;
 using GitHub.Runner.Listener.Configuration;
 using GitHub.Runner.Worker;
+using GitHub.Runner.Worker.Container.ContainerHooks;
 using GitHub.Runner.Worker.Handlers;
 using System;
 using System.Collections.Generic;
@@ -68,7 +69,8 @@ namespace GitHub.Runner.Common.Tests
                 typeof(IStep),
                 typeof(IStepHost),
                 typeof(IDiagnosticLogManager),
-                typeof(IEnvironmentContextData)
+                typeof(IEnvironmentContextData),
+                typeof(IHookArgs),                
             };
             Validate(
                 assembly: typeof(IStepsRunner).GetTypeInfo().Assembly,

src/Test/L0/Worker/CreateStepSummaryCommandL0.cs

@@ -25,23 +25,6 @@ namespace GitHub.Runner.Common.Tests.Worker
         private CreateStepSummaryCommand _createStepCommand;
         private ITraceWriter _trace;
 
-        [Fact]
-        [Trait("Level", "L0")]
-        [Trait("Category", "Worker")]
-        public void CreateStepSummaryCommand_FeatureDisabled()
-        {
-            using (var hostContext = Setup(featureFlagState: "false"))
-            {
-                var stepSummaryFile = Path.Combine(_rootDirectory, "feature-off");
-
-                _createStepCommand.ProcessCommand(_executionContext.Object, stepSummaryFile, null);
-                _jobExecutionContext.Complete();
-
-                _jobServerQueue.Verify(x => x.QueueFileUpload(It.IsAny<Guid>(), It.IsAny<Guid>(), It.IsAny<string>(), It.IsAny<string>(), It.IsAny<string>(), It.IsAny<bool>()), Times.Never());
-                Assert.Equal(0, _issues.Count);
-            }
-        }
-
         [Fact]
         [Trait("Level", "L0")]
         [Trait("Category", "Worker")]
@@ -199,7 +182,7 @@ namespace GitHub.Runner.Common.Tests.Worker
             File.WriteAllText(path, contentStr, encoding);
         }
 
-        private TestHostContext Setup([CallerMemberName] string name = "", string featureFlagState = "true")
+        private TestHostContext Setup([CallerMemberName] string name = "")
         {
             var hostContext = new TestHostContext(this, name);
 
@@ -241,7 +224,6 @@ namespace GitHub.Runner.Common.Tests.Worker
             _variables = new Variables(hostContext, new Dictionary<string, VariableValue>
                 {
                     { "MySecretName", new VariableValue("My secret value", true) },
-                    { "DistributedTask.UploadStepSummary", featureFlagState },
                 });
 
             // Directory for test data

src/Test/L0/Worker/ExecutionContextL0.cs

@@ -100,7 +100,6 @@ namespace GitHub.Runner.Common.Tests.Worker
         {
             using (TestHostContext hc = CreateTestContext())
             {
-
                 // Arrange: Create a job request message.
                 TaskOrchestrationPlanReference plan = new TaskOrchestrationPlanReference();
                 TimelineReference timeline = new TimelineReference();

src/Test/L0/Worker/JobExtensionL0.cs

@@ -211,6 +211,24 @@ namespace GitHub.Runner.Common.Tests.Worker
             }
         }
 
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        public async Task JobExtensionBuildFailsWithoutContainerIfRequired()
+        {
+            Environment.SetEnvironmentVariable(Constants.Variables.Actions.RequireJobContainer, "true");
+            using (TestHostContext hc = CreateTestContext())
+            {
+                var jobExtension = new JobExtension();
+                jobExtension.Initialize(hc);
+
+                _actionManager.Setup(x => x.PrepareActionsAsync(It.IsAny<IExecutionContext>(), It.IsAny<IEnumerable<Pipelines.JobStep>>(), It.IsAny<Guid>()))
+                              .Returns(Task.FromResult(new PrepareResult(new List<JobExtensionRunner>() { new JobExtensionRunner(null, "", "prepare1", null), new JobExtensionRunner(null, "", "prepare2", null) }, new Dictionary<Guid, IActionRunner>())));
+
+                await Assert.ThrowsAsync<ArgumentException>(() => jobExtension.InitializeJob(_jobEc, _message));
+            }
+        }
+
         [Fact]
         [Trait("Level", "L0")]
         [Trait("Category", "Worker")]

src/Test/L0/Worker/StepHostL0.cs

@@ -10,6 +10,7 @@ using GitHub.Runner.Worker.Container;
 using GitHub.DistributedTask.Pipelines.ContextData;
 using System.Linq;
 using GitHub.DistributedTask.Pipelines;
+using GitHub.DistributedTask.WebApi;
 
 namespace GitHub.Runner.Common.Tests.Worker
 {
@@ -24,6 +25,7 @@ namespace GitHub.Runner.Common.Tests.Worker
             _ec = new Mock<IExecutionContext>();
             _ec.SetupAllProperties();
             _ec.Setup(x => x.Global).Returns(new GlobalContext { WriteDebug = true });
+            _ec.Object.Global.Variables = new Variables(hc, new Dictionary<string, VariableValue>());
             var trace = hc.GetTrace();
             _ec.Setup(x => x.Write(It.IsAny<string>(), It.IsAny<string>())).Callback((string tag, string message) => { trace.Info($"[{tag}]{message}"); });
 

src/runnerversion

@@ -1 +1 @@
-2.292.0
+2.293.2