Scaffold a new action with --init (-i) flag

actions/api.go

@@ -44,6 +44,8 @@ type RunnerConfig struct {
 	EventPath       string          // path to JSON file to use for event.json in containers, relative to WorkingDir
 	ReuseContainers bool            // reuse containers to maintain state
 	ForcePull       bool            // force pulling of the image, if already present
+	Init            bool            // init a new action
+	InitRepo        string          // git repo to pull template from
 }
 
 type environmentApplier interface {

cmd/root.go

@@ -3,6 +3,7 @@ package cmd
 import (
 	"context"
 	"fmt"
+	"io/ioutil"
 	"os"
 	"path/filepath"
 
@@ -12,6 +13,7 @@ import (
 	gitignore "github.com/sabhiram/go-gitignore"
 	log "github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
+	git "gopkg.in/src-d/go-git.v4"
 )
 
 // Execute is the entry point to running the CLI
@@ -26,20 +28,23 @@ func Execute(ctx context.Context, version string) {
 		Version:          version,
 		SilenceUsage:     true,
 	}
+
 	rootCmd.Flags().BoolP("watch", "w", false, "watch the contents of the local repo and run when files change")
 	rootCmd.Flags().BoolP("list", "l", false, "list actions")
 	rootCmd.Flags().StringP("action", "a", "", "run action")
+	rootCmd.Flags().BoolVarP(&runnerConfig.Init, "init", "i", false, "init the local action")
+	rootCmd.Flags().StringVarP(&runnerConfig.InitRepo, "init-repo", "", "https://github.com/nektos/act", "init template repository")
 	rootCmd.Flags().BoolVarP(&runnerConfig.ReuseContainers, "reuse", "r", false, "reuse action containers to maintain state")
 	rootCmd.Flags().StringVarP(&runnerConfig.EventPath, "event", "e", "", "path to event JSON file")
 	rootCmd.Flags().BoolVarP(&runnerConfig.ForcePull, "pull", "p", false, "pull docker image(s) if already present")
 	rootCmd.PersistentFlags().BoolP("verbose", "v", false, "verbose output")
 	rootCmd.PersistentFlags().BoolVarP(&runnerConfig.Dryrun, "dryrun", "n", false, "dryrun mode")
 	rootCmd.PersistentFlags().StringVarP(&runnerConfig.WorkflowPath, "file", "f", "./.github/main.workflow", "path to workflow file")
 	rootCmd.PersistentFlags().StringVarP(&runnerConfig.WorkingDir, "directory", "C", ".", "working directory")
+
 	if err := rootCmd.Execute(); err != nil {
 		os.Exit(1)
 	}
-
 }
 
 func setupLogging(cmd *cobra.Command, args []string) {
@@ -69,6 +74,15 @@ func newRunCommand(runnerConfig *actions.RunnerConfig) func(*cobra.Command, []st
 }
 
 func parseAndRun(cmd *cobra.Command, runnerConfig *actions.RunnerConfig) error {
+	// check if we should scaffold a new action
+	init, err := cmd.Flags().GetBool("init")
+	if err != nil {
+		return err
+	}
+	if init {
+		return initAction(runnerConfig)
+	}
+
 	// create the runner
 	runner, err := actions.NewRunner(runnerConfig)
 	if err != nil {
@@ -156,6 +170,50 @@ func watchAndRun(ctx context.Context, fn func() error) error {
 	return err
 }
 
+func initAction(config *actions.RunnerConfig) error {
+	// use the default event name if we don't have one
+	if config.EventName == "" {
+		config.EventName = "push"
+	}
+
+	log.Printf("Setting up a new action for %s event\n", config.EventName)
+	baseDir := filepath.Dir(config.WorkflowPath)
+
+	// check if workflow directory exists, skip setup if it's already configured
+	if _, err := os.Stat(baseDir); err == nil {
+		log.Println("Workspace directory already exists, skipping")
+		return nil
+	}
+
+	// prepare clone repository
+	repoCloneDir, err := ioutil.TempDir("", "act")
+	if err != nil {
+		log.Println("Can't get temp directory for clone:", err)
+		return err
+	}
+	defer os.RemoveAll(repoCloneDir)
+
+	// clone repository
+	_, err = git.PlainClone(repoCloneDir, false, &git.CloneOptions{
+		URL: config.InitRepo,
+	})
+	if err != nil {
+		log.Println("Can't clone repository:", err)
+		return err
+	}
+
+	// copy template
+	templateDir := filepath.Join(repoCloneDir, "templates/"+config.EventName)
+	if err := common.CopyDir(templateDir, baseDir); err != nil {
+		log.Println("Can't copy template:", err)
+		return err
+	}
+
+	log.Printf("Done. You can now run `act %s` to test things out!", config.EventName)
+
+	return nil
+}
+
 func drawGraph(runner actions.Runner) error {
 	eventNames := runner.ListEvents()
 	for _, eventName := range eventNames {

common/file.go

@@ -7,31 +7,29 @@ import (
 )
 
 // CopyFile copy file
-func CopyFile(source string, dest string) (err error) {
+func CopyFile(source string, dest string) error {
 	sourcefile, err := os.Open(source)
 	if err != nil {
 		return err
 	}
-
 	defer sourcefile.Close()
 
 	destfile, err := os.Create(dest)
 	if err != nil {
 		return err
 	}
-
 	defer destfile.Close()
 
-	_, err = io.Copy(destfile, sourcefile)
-	if err == nil {
-		sourceinfo, err := os.Stat(source)
-		if err != nil {
-			_ = os.Chmod(dest, sourceinfo.Mode())
-		}
+	if _, err = io.Copy(destfile, sourcefile); err != nil {
+		return err
+	}
 
+	sourceinfo, err := os.Stat(source)
+	if err != nil {
+		return err
 	}
 
-	return
+	return os.Chmod(dest, sourceinfo.Mode())
 }
 
 // CopyDir recursive copy of directory

templates/push/action/Dockerfile

@@ -0,0 +1,3 @@
+FROM alpine:latest
+COPY entrypoint.sh /entrypoint.sh
+ENTRYPOINT ["/entrypoint.sh"]

templates/push/action/entrypoint.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+
+echo "Hello World"

templates/push/main.workflow

@@ -0,0 +1,8 @@
+workflow "basic workflow" {
+	on = "push"
+	resolves = ["example"]
+}
+
+action "example" {
+  uses = "./.github/action"
+}