Force JS Actions Node version to 16 if FF is on unless user opted out (#1716)

* Set GH actions Node version to 16 if FF is on unless user opted out

* Add L0s (WIP)

* Wrap tests into theory

* Only check for node12 actions

* Refactor node version picking

src/Runner.Common/Constants.cs

@@ -220,6 +220,7 @@ namespace GitHub.Runner.Common
                 public static readonly string AllowUnsupportedStopCommandTokens = "ACTIONS_ALLOW_UNSECURE_STOPCOMMAND_TOKENS";
                 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";
             }
 
             public static class Agent

src/Runner.Worker/Handlers/HandlerFactory.cs

@@ -55,7 +55,23 @@ namespace GitHub.Runner.Worker.Handlers
             else if (data.ExecutionType == ActionExecutionType.NodeJS)
             {
                 handler = HostContext.CreateService<INodeScriptActionHandler>();
-                (handler as INodeScriptActionHandler).Data = data as NodeJSActionExecutionData;
+                var nodeData = data as NodeJSActionExecutionData;
+
+                // With node12 EoL in 04/2022, we want to be able to uniformly upgrade all JS actions to node16 from the server
+                if (string.Equals(nodeData.NodeVersion, "node12", StringComparison.InvariantCultureIgnoreCase) &&
+                    (executionContext.Global.Variables.GetBoolean("DistributedTask.ForceGithubJavascriptActionsToNode16") ?? false))
+                {
+                    // The user can opt out of this behaviour by setting this variable to true, either setting 'env' in their workflow or as an environment variable on their machine
+                    executionContext.Global.EnvironmentVariables.TryGetValue(Constants.Variables.Actions.AllowActionsUseUnsecureNodeVersion, out var workflowOptOut);
+                    var isWorkflowOptOutSet = !string.IsNullOrEmpty(workflowOptOut);
+                    var isLocalOptOut = StringUtil.ConvertToBoolean(Environment.GetEnvironmentVariable(Constants.Variables.Actions.AllowActionsUseUnsecureNodeVersion));
+                    bool isOptOut = isWorkflowOptOutSet ? StringUtil.ConvertToBoolean(workflowOptOut) : isLocalOptOut;
+                    if (!isOptOut)
+                    {
+                        nodeData.NodeVersion = "node16";
+                    }
+                }
+                (handler as INodeScriptActionHandler).Data = nodeData;
             }
             else if (data.ExecutionType == ActionExecutionType.Script)
             {

src/Test/L0/Worker/HandlerFactoryL0.cs

@@ -0,0 +1,100 @@
+using System;
+using System.Collections.Generic;
+using System.Runtime.CompilerServices;
+using Moq;
+using Xunit;
+using GitHub.Runner.Worker;
+using GitHub.Runner.Worker.Handlers;
+using GitHub.DistributedTask.Pipelines;
+using GitHub.DistributedTask.WebApi;
+
+namespace GitHub.Runner.Common.Tests.Worker
+{
+    public sealed class HandlerFactoryL0
+    {
+        private Mock<IExecutionContext> _ec;
+        private TestHostContext CreateTestContext([CallerMemberName] string testName = "")
+        {
+            var hostContext = new TestHostContext(this, testName);
+            _ec = new Mock<IExecutionContext>();
+            _ec.SetupAllProperties();
+            _ec.Object.Initialize(hostContext);
+            var handler = new Mock<INodeScriptActionHandler>();
+            handler.SetupAllProperties();
+            hostContext.EnqueueInstance(handler.Object);
+            //hostContext.EnqueueInstance(new ActionCommandManager() as IActionCommandManager);
+
+            return hostContext;
+        }
+
+        [Theory]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        [InlineData("node12", "", "", "", "node12")]
+        [InlineData("node12", "true", "", "", "node16")]
+        [InlineData("node12", "true", "", "true", "node12")]
+        [InlineData("node12", "true", "true", "", "node12")]
+        [InlineData("node12", "true", "true", "true", "node12")]
+        [InlineData("node12", "true", "false", "true", "node16")] // workflow overrides env
+        [InlineData("node16", "", "", "", "node16")]
+        [InlineData("node16", "true", "", "", "node16")]
+        [InlineData("node16", "true", "", "true", "node16")]
+        [InlineData("node16", "true", "true", "", "node16")]
+        [InlineData("node16", "true", "true", "true", "node16")]
+        [InlineData("node16", "true", "false", "true", "node16")]
+        public void IsNodeVersionUpgraded(string inputVersion, string serverFeatureFlag, string workflowOptOut, string machineOptOut, string expectedVersion)
+        {
+            using (TestHostContext hc = CreateTestContext())
+            {
+                // Arrange.
+                var hf = new HandlerFactory();
+                hf.Initialize(hc);
+
+                // Server Feature Flag
+                var variables = new Dictionary<string, VariableValue>();
+                if (!string.IsNullOrEmpty(serverFeatureFlag))
+                {
+                    variables["DistributedTask.ForceGithubJavascriptActionsToNode16"] = serverFeatureFlag;
+                }
+                Variables serverVariables = new Variables(hc, variables);
+
+                // Workflow opt-out
+                var workflowVariables = new Dictionary<string, string>();
+                if (!string.IsNullOrEmpty(workflowOptOut))
+                {
+                    workflowVariables[Constants.Variables.Actions.AllowActionsUseUnsecureNodeVersion] = workflowOptOut;
+                }
+
+                // Machine opt-out
+                if (!string.IsNullOrEmpty(machineOptOut))
+                {
+                    Environment.SetEnvironmentVariable(Constants.Variables.Actions.AllowActionsUseUnsecureNodeVersion, machineOptOut);
+                }
+
+                _ec.Setup(x => x.Global).Returns(new GlobalContext()
+                {
+                    Variables = serverVariables,
+                    EnvironmentVariables = workflowVariables
+                });
+
+
+                // Act.
+                var data = new NodeJSActionExecutionData();
+                data.NodeVersion = inputVersion;
+                var handler = hf.Create(
+                    _ec.Object,
+                    new ScriptReference(),
+                    new Mock<IStepHost>().Object,
+                    data,
+                    new Dictionary<string, string>(),
+                    new Dictionary<string, string>(),
+                    new Variables(hc, new Dictionary<string, VariableValue>()), "", new List<JobExtensionRunner>()
+                ) as INodeScriptActionHandler;
+
+                // Assert.
+                Assert.Equal(expectedVersion, handler.Data.NodeVersion);
+                Environment.SetEnvironmentVariable(Constants.Variables.Actions.AllowActionsUseUnsecureNodeVersion, null);
+            }
+        }
+    }
+}