Support container removal at exit. Fixes #694 (#714)

This patch adds a new command-line flag (`--rm`) to automatically
stop workflow container(s), just prior to exit. The default
behavior is kept, e.g.: the containers continue running at exit.

Fixes: #694
Signed-off-by: Joseph Benden <joe@benden.us>

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

cmd/input.go

@@ -34,6 +34,7 @@ type Input struct {
 	githubInstance        string
 	containerCapAdd       []string
 	containerCapDrop      []string
+	autoRemove            bool
 }
 
 func (i *Input) resolve(path string) string {

cmd/root.go

@@ -52,6 +52,7 @@ func Execute(ctx context.Context, version string) {
 	rootCmd.Flags().BoolVar(&input.useGitIgnore, "use-gitignore", true, "Controls whether paths specified in .gitignore should be copied into container")
 	rootCmd.Flags().StringArrayVarP(&input.containerCapAdd, "container-cap-add", "", []string{}, "kernel capabilities to add to the workflow containers (e.g. --container-cap-add SYS_PTRACE)")
 	rootCmd.Flags().StringArrayVarP(&input.containerCapDrop, "container-cap-drop", "", []string{}, "kernel capabilities to remove from the workflow containers (e.g. --container-cap-drop SYS_PTRACE)")
+	rootCmd.Flags().BoolVar(&input.autoRemove, "rm", false, "automatically remove containers just before exit")
 	rootCmd.PersistentFlags().StringVarP(&input.actor, "actor", "a", "nektos/act", "user that triggered the event")
 	rootCmd.PersistentFlags().StringVarP(&input.workflowsPath, "workflows", "W", "./.github/workflows/", "path to workflow file(s)")
 	rootCmd.PersistentFlags().BoolVarP(&input.noWorkflowRecurse, "no-recurse", "", false, "Flag to disable running workflows from subdirectories of specified path in '--workflows'/'-W' flag")
@@ -263,6 +264,7 @@ func newRunCommand(ctx context.Context, input *Input) func(*cobra.Command, []str
 			GitHubInstance:        input.githubInstance,
 			ContainerCapAdd:       input.containerCapAdd,
 			ContainerCapDrop:      input.containerCapDrop,
+			AutoRemove:            input.autoRemove,
 		}
 		r, err := runner.New(config)
 		if err != nil {

pkg/runner/runner.go

@@ -42,6 +42,7 @@ type Config struct {
 	GitHubInstance        string            // GitHub instance to use, default "github.com"
 	ContainerCapAdd       []string          // list of kernel capabilities to add to the containers
 	ContainerCapDrop      []string          // list of kernel capabilities to remove from the containers
+	AutoRemove            bool              // controls if the container is automatically removed upon workflow completion
 }
 
 // Resolves the equivalent host path inside the container
@@ -111,9 +112,9 @@ func (runner *runnerImpl) NewPlanExecutor(plan *model.Plan) common.Executor {
 	maxJobNameLen := 0
 
 	pipeline := make([]common.Executor, 0)
-	for _, stage := range plan.Stages {
+	for s, stage := range plan.Stages {
 		stageExecutor := make([]common.Executor, 0)
-		for _, run := range stage.Runs {
+		for r, run := range stage.Runs {
 			job := run.Job()
 			matrixes := job.GetMatrixes()
 
@@ -128,7 +129,20 @@ func (runner *runnerImpl) NewPlanExecutor(plan *model.Plan) common.Executor {
 				}
 				stageExecutor = append(stageExecutor, func(ctx context.Context) error {
 					jobName := fmt.Sprintf("%-*s", maxJobNameLen, rc.String())
-					return rc.Executor()(WithJobLogger(ctx, jobName, rc.Config.Secrets, rc.Config.InsecureSecrets))
+					return rc.Executor().Finally(func(ctx context.Context) error {
+						isLastRunningContainer := func(currentStage int, currentRun int) bool {
+							return currentStage == len(plan.Stages)-1 && currentRun == len(stage.Runs)-1
+						}
+
+						if runner.config.AutoRemove && isLastRunningContainer(s, r) {
+							log.Infof("Cleaning up container for job %s", rc.JobName)
+							if err := rc.stopJobContainer()(ctx); err != nil {
+								log.Errorf("Error while cleaning container: %v", err)
+							}
+						}
+
+						return nil
+					})(WithJobLogger(ctx, jobName, rc.Config.Secrets, rc.Config.InsecureSecrets))
 				})
 			}
 		}