add support for 'reuse' mode to allow act to be used for a fast local task runner

.github/actions/check/Dockerfile

@@ -1,10 +1,6 @@
-FROM golang:1.11.4-stretch
-
-RUN go get -u honnef.co/go/tools/cmd/staticcheck
-RUN go get -u golang.org/x/lint/golint
-RUN go get -u github.com/fzipp/gocyclo
+FROM golangci/golangci-lint:v1.12.5
 
 COPY "entrypoint.sh" "/entrypoint.sh"
 RUN chmod +x /entrypoint.sh
 
-ENTRYPOINT ["/entrypoint.sh"]
+ENTRYPOINT ["/entrypoint.sh"]

.github/actions/check/entrypoint.sh

@@ -1,10 +1,4 @@
 #!/bin/sh 
 
-#GOPATH=/go
-#PATH=${GOPATH}/bin:/usr/local/go/bin:${PATH}
-
-go vet ./...
-golint -set_exit_status ./...
-staticcheck ./...
-gocyclo -over 10 .
+golangci-lint run
 go test -cover ./...

.github/main.workflow

@@ -7,15 +7,21 @@ action "check" {
   uses = "./.github/actions/check"
 }
 
- action "branch-filter" {
+action "branch-filter" {
   needs = ["check"]
   uses = "actions/bin/filter@master"
   args = "tag v*"
- }
+}
 
- action "release" {
+action "release" {
   needs = ["branch-filter"]
   uses = "docker://goreleaser/goreleaser:v0.97"
   args = "release"
   secrets = ["GITHUB_TOKEN"]
- }
+}
+
+action "build" {
+  uses = "docker://goreleaser/goreleaser:v0.97"
+  args = "--snapshot --rm-dist"
+  secrets = ["SNAPSHOT_VERSION"]
+}

actions/api.go

@@ -36,12 +36,13 @@ type ActionRunner interface {
 
 // RunnerConfig contains the config for a new runner
 type RunnerConfig struct {
-	Ctx          context.Context // context to use for the run
-	Dryrun       bool            // don't start any of the containers
-	WorkingDir   string          // base directory to use
-	WorkflowPath string          // path to load main.workflow file, relative to WorkingDir
-	EventName    string          // name of event to run
-	EventPath    string          // path to JSON file to use for event.json in containers, relative to WorkingDir
+	Ctx             context.Context // context to use for the run
+	Dryrun          bool            // don't start any of the containers
+	WorkingDir      string          // base directory to use
+	WorkflowPath    string          // path to load main.workflow file, relative to WorkingDir
+	EventName       string          // name of event to run
+	EventPath       string          // path to JSON file to use for event.json in containers, relative to WorkingDir
+	ReuseContainers bool            // reuse containers to maintain state
 }
 
 type environmentApplier interface {

actions/runner_exec.go

@@ -5,7 +5,6 @@ import (
 	"bytes"
 	"fmt"
 	"io"
-	"math/rand"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -78,11 +77,6 @@ func (runner *runnerImpl) newActionExecutor(actionName string) common.Executor {
 	if err != nil {
 		return common.NewErrorExecutor(err)
 	}
-	randSuffix := randString(6)
-	containerName := regexp.MustCompile("[^a-zA-Z0-9]").ReplaceAllString(actionName, "-")
-	if len(containerName)+len(randSuffix)+1 > 30 {
-		containerName = containerName[:(30 - (len(randSuffix) + 1))]
-	}
 
 	envList := make([]string, 0)
 	for k, v := range env {
@@ -95,13 +89,14 @@ func (runner *runnerImpl) newActionExecutor(actionName string) common.Executor {
 		Image:               image,
 		WorkingDir:          "/github/workspace",
 		Env:                 envList,
-		Name:                fmt.Sprintf("%s-%s", containerName, randSuffix),
+		Name:                runner.createContainerName(actionName),
 		Binds: []string{
 			fmt.Sprintf("%s:%s", runner.config.WorkingDir, "/github/workspace"),
 			fmt.Sprintf("%s:%s", runner.tempDir, "/github/home"),
 			fmt.Sprintf("%s:%s", "/var/run/docker.sock", "/var/run/docker.sock"),
 		},
-		Content: map[string]io.Reader{"/github": ghReader},
+		Content:         map[string]io.Reader{"/github": ghReader},
+		ReuseContainers: runner.config.ReuseContainers,
 	}))
 
 	return common.NewPipelineExecutor(executors...)
@@ -174,12 +169,18 @@ func (runner *runnerImpl) createGithubTarball() (io.Reader, error) {
 
 }
 
-const letterBytes = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+func (runner *runnerImpl) createContainerName(actionName string) string {
+	containerName := regexp.MustCompile("[^a-zA-Z0-9]").ReplaceAllString(actionName, "-")
 
-func randString(slen int) string {
-	b := make([]byte, slen)
-	for i := range b {
-		b[i] = letterBytes[rand.Int63()%int64(len(letterBytes))]
-	}
-	return string(b)
+	prefix := fmt.Sprintf("%s-", trimToLen(filepath.Base(runner.config.WorkingDir), 10))
+	suffix := ""
+	containerName = trimToLen(containerName, 30-(len(prefix)+len(suffix)))
+	return fmt.Sprintf("%s%s%s", prefix, containerName, suffix)
+}
+
+func trimToLen(s string, l int) string {
+	if len(s) > l {
+		return s[:l]
+	}
+	return s
 }

cmd/root.go

@@ -25,6 +25,7 @@ func Execute(ctx context.Context, version string) {
 	}
 	rootCmd.Flags().BoolP("list", "l", false, "list actions")
 	rootCmd.Flags().StringP("action", "a", "", "run action")
+	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.PersistentFlags().BoolP("verbose", "v", false, "verbose output")
 	rootCmd.PersistentFlags().BoolVarP(&runnerConfig.Dryrun, "dryrun", "n", false, "dryrun mode")

container/docker_run.go

@@ -16,15 +16,16 @@ import (
 // NewDockerRunExecutorInput the input for the NewDockerRunExecutor function
 type NewDockerRunExecutorInput struct {
 	DockerExecutorInput
-	Image      string
-	Entrypoint []string
-	Cmd        []string
-	WorkingDir string
-	Env        []string
-	Binds      []string
-	Content    map[string]io.Reader
-	Volumes    []string
-	Name       string
+	Image           string
+	Entrypoint      []string
+	Cmd             []string
+	WorkingDir      string
+	Env             []string
+	Binds           []string
+	Content         map[string]io.Reader
+	Volumes         []string
+	Name            string
+	ReuseContainers bool
 }
 
 // NewDockerRunExecutor function to create a run executor for the container
@@ -41,29 +42,44 @@ func NewDockerRunExecutor(input NewDockerRunExecutorInput) common.Executor {
 			return err
 		}
 
-		containerID, err := createContainer(input, cli)
-		if err != nil {
-			return err
-		}
-		defer removeContainer(input, cli, containerID)
-
-		err = copyContentToContainer(input, cli, containerID)
+		// check if container exists
+		containerID, err := findContainer(input, cli, input.Name)
 		if err != nil {
 			return err
 		}
 
-		err = attachContainer(input, cli, containerID)
-		if err != nil {
-			return err
+		// if we have an old container and we aren't reusing, remove it!
+		if !input.ReuseContainers && containerID != "" {
+			input.Logger.Debugf("Found existing container for %s...removing", input.Name)
+			removeContainer(input, cli, containerID)
+			containerID = ""
 		}
 
-		err = startContainer(input, cli, containerID)
-		if err != nil {
-			return err
+		// create a new container if we don't have one to reuse
+		if containerID == "" {
+			containerID, err = createContainer(input, cli)
+			if err != nil {
+				return err
+			}
 		}
 
-		return waitContainer(input, cli, containerID)
+		// be sure to cleanup container if we aren't reusing
+		if !input.ReuseContainers {
+			defer removeContainer(input, cli, containerID)
+		}
 
+		executor := common.NewPipelineExecutor(
+			func() error {
+				return copyContentToContainer(input, cli, containerID)
+			}, func() error {
+				return attachContainer(input, cli, containerID)
+			}, func() error {
+				return startContainer(input, cli, containerID)
+			}, func() error {
+				return waitContainer(input, cli, containerID)
+			},
+		)
+		return executor()
 	}
 
 }
@@ -99,6 +115,25 @@ func createContainer(input NewDockerRunExecutorInput, cli *client.Client) (strin
 	return resp.ID, nil
 }
 
+func findContainer(input NewDockerRunExecutorInput, cli *client.Client, containerName string) (string, error) {
+	containers, err := cli.ContainerList(input.Ctx, types.ContainerListOptions{
+		All: true,
+	})
+	if err != nil {
+		return "", err
+	}
+
+	for _, container := range containers {
+		for _, name := range container.Names {
+			if name[1:] == containerName {
+				return container.ID, nil
+			}
+		}
+	}
+
+	return "", nil
+}
+
 func removeContainer(input NewDockerRunExecutorInput, cli *client.Client, containerID string) {
 	err := cli.ContainerRemove(context.Background(), containerID, types.ContainerRemoveOptions{
 		RemoveVolumes: true,