Add option to mount the docker socket

docker.go

@@ -27,9 +27,10 @@ import (
 const (
 	minimumDockerVersion = "1.25"
 	tgfImageVersion      = "TGF_IMAGE_VERSION"
+	dockerSocketFile     = "/var/run/docker.sock"
 )
 
-func callDocker(args ...string) int {
+func callDocker(withDockerMount bool, args ...string) int {
 	command := append([]string{config.EntryPoint}, args...)
 
 	// Change the default log level for terragrunt
@@ -71,6 +72,12 @@ func callDocker(args ...string) int {
 		"-v", fmt.Sprintf("%s%s:%s", convertDrive(currentDrive), rootFolder, filepath.ToSlash(filepath.Join("/", mountPoint, rootFolder))),
 		"-w", sourceFolder,
 	}
+
+	if withDockerMount {
+		withDockerMountArgs := []string{"-v", fmt.Sprintf(dockerSocketMountPattern, dockerSocketFile), "--group-add", getDockerGroup()}
+		dockerArgs = append(dockerArgs, withDockerMountArgs...)
+	}
+
 	if !noHome {
 		currentUser := must(user.Current()).(*user.User)
 		home := filepath.ToSlash(currentUser.HomeDir)

docker_unix.go

@@ -0,0 +1,20 @@
+package main
+
+import (
+	"github.com/coveo/gotemplate/utils"
+	"os"
+	"strings"
+)
+
+const dockerSocketMountPattern = "%[1]s:%[1]s"
+
+func getDockerGroup() string {
+	cmd, tempFile, err := utils.GetCommandFromString("stat -c '%g' " + dockerSocketFile)
+	if err != nil {
+		panic(err)
+	}
+	if tempFile != "" {
+		defer func() { os.Remove(tempFile) }()
+	}
+	return strings.TrimSpace(string(must(cmd.Output()).([]byte)))
+}

docker_windows.go

@@ -0,0 +1,7 @@
+package main
+
+const dockerSocketMountPattern = "/%[1]s:%[1]s"
+
+func getDockerGroup() string {
+	return "root"
+}

main.go

@@ -141,6 +141,7 @@ func main() {
 		getAllVersions    = app.Switch("all-versions", "Get versions of TGF & all others underlying utilities (alias --av)").Bool()
 		pruneImages       = app.Switch("prune", "Remove all previous versions of the targeted image").Bool()
 		getCurrentVersion = app.Switch("current-version", "Get current version information (alias --cv)").Bool()
+		withDockerMount   = app.Switch("with-docker-mount", "Mounts the docker socket to the image so the host's docker api is usable (alias --wd)").Bool()
 		entrypoint        = app.Argument("entrypoint", "Override the entry point for docker", 'E').PlaceHolder("terragrunt").String()
 		image             = app.Argument("image", "Use the specified image instead of the default one").PlaceHolder("coveo/tgf").String()
 		imageVersion      = app.Argument("image-version", "Use a different version of docker image instead of the default one (alias --iv)").PlaceHolder("version").Default("-").String()
@@ -155,6 +156,7 @@ func main() {
 	app.Switch("nt", "alias for no-temp").Hidden().BoolVar(&noTemp)
 	app.Switch("cv", "alias for current-version").Hidden().BoolVar(getCurrentVersion)
 	app.Switch("av", "alias for all-versions").Hidden().BoolVar(getAllVersions)
+	app.Switch("wd", "alias for with-docker").Hidden().BoolVar(withDockerMount)
 	app.Argument("da", "alias for docker-arg").Hidden().StringsVar(&dockerOptions)
 	app.Argument("iv", "alias for image-version").Default("-").Hidden().StringVar(imageVersion)
 	app.Argument("mp", "alias for mount-point").Hidden().StringVar(&mountPoint)
@@ -234,7 +236,7 @@ func main() {
 		}
 	}
 
-	os.Exit(callDocker(unmanaged...))
+	os.Exit(callDocker(*withDockerMount, unmanaged...))
 }
 
 func validateVersion(version string) bool {