From 84e552823741fbc6ebb441c538b70ee1bb504845 Mon Sep 17 00:00:00 2001
From: Mathieu Frenette <silphid@users.noreply.github.com>
Date: Tue, 22 Jun 2021 19:25:08 -0400
Subject: [PATCH] Add --dry-run and --verbose flags

---
 src/cmd/run/run.go         | 43 ++++++++++++++++++++++++++++++++------
 src/internal/docker/cli.go | 34 +++++++++++++++++++++++++++---
 2 files changed, 68 insertions(+), 9 deletions(-)

diff --git a/src/cmd/run/run.go b/src/cmd/run/run.go
index 8e9b451..6d2056f 100644
--- a/src/cmd/run/run.go
+++ b/src/cmd/run/run.go
@@ -33,13 +33,17 @@ func New() *cobra.Command {
 
 	cmd.Flags().BoolVar(options.Remove, "rm", false, "remove container upon exit")
 	cmd.Flags().BoolVar(&options.Reset, "reset", false, "remove previous container before starting a fresh one")
+	cmd.Flags().BoolVarP(&options.Verbose, "verbose", "v", false, "output detailed execution information to stderr")
+	cmd.Flags().BoolVar(&options.DryRun, "dry-run", false, "output docker command to stdout instead of executing it")
 
 	return cmd
 }
 
 type Options struct {
-	Remove *bool
-	Reset  bool
+	Remove  *bool
+	Reset   bool
+	Verbose bool
+	DryRun  bool
 }
 
 func run(ctx context.Context, names []string, options Options) error {
@@ -70,26 +74,53 @@ func run(ctx context.Context, names []string, options Options) error {
 		logging.Log("using image: %s", yeyContext.Image)
 	}
 
+	if options.Verbose {
+		fmt.Fprintf(os.Stderr, "context:\n--\n%v--\n", yeyContext)
+	}
+
+	// Container name
 	containerName := yey.ContainerName(contexts.Path, yeyContext)
+	if options.Verbose {
+		fmt.Fprintf(os.Stderr, "container: %s\n", containerName)
+	}
 
+	// Reset
 	if options.Reset {
+		if options.Verbose {
+			fmt.Fprintf(os.Stderr, "removing container first")
+		}
 		if err := docker.Remove(ctx, containerName); err != nil {
 			return fmt.Errorf("failed to remove container %q: %w", containerName, err)
 		}
 	}
 
+	var runOptions []docker.RunOption
+
+	// Working directory
 	workDir, err := getContainerWorkDir(yeyContext)
 	if err != nil {
 		return err
 	}
-
-	var runOptions []docker.RunOption
 	if workDir != "" {
 		runOptions = append(runOptions, docker.WithWorkDir(workDir))
 	}
+	if options.Verbose {
+		fmt.Fprintf(os.Stderr, "working directory: %s", workDir)
+	}
 
-	if err := ShowBanner(yeyContext.Name); err != nil {
-		return err
+	// Dry-run/verbose
+	runOptions = append(runOptions,
+		docker.WithDryRun(options.DryRun),
+		docker.WithVerbose(options.Verbose))
+
+	// Banner
+	if options.Verbose {
+		fmt.Fprintln(os.Stderr)
+	}
+	if !options.DryRun {
+		if err := ShowBanner(yeyContext.Name); err != nil {
+			return err
+		}
 	}
 
 	return docker.Start(ctx, yeyContext, containerName, runOptions...)
diff --git a/src/internal/docker/cli.go b/src/internal/docker/cli.go
index fd9fb7c..a0a37ce 100644
--- a/src/internal/docker/cli.go
+++ b/src/internal/docker/cli.go
@@ -16,6 +16,8 @@ import (
 
 type runOptions struct {
 	workDir string
+	verbose bool
+	dryRun  bool
 }
 
 type RunOption func(*runOptions)
@@ -26,6 +28,18 @@ func WithWorkDir(wd string) RunOption {
 	}
 }
 
+func WithVerbose(value bool) RunOption {
+	return func(ro *runOptions) {
+		ro.verbose = value
+	}
+}
+
+func WithDryRun(value bool) RunOption {
+	return func(ro *runOptions) {
+		ro.dryRun = value
+	}
+}
+
 func Start(ctx context.Context, yeyCtx yey.Context, containerName string, opts ...RunOption) error {
 	var options runOptions
 	for _, opt := range opts {
@@ -42,7 +56,7 @@ func Start(ctx context.Context, yeyCtx yey.Context, containerName string, opts .
 	case "":
 		return runContainer(ctx, yeyCtx, containerName, options)
 	case "exited":
-		return startContainer(ctx, containerName)
+		return startContainer(ctx, containerName, options)
 	case "running":
 		return execContainer(ctx, containerName, yeyCtx.Cmd, options)
 	default:
@@ -205,11 +219,21 @@ func runContainer(ctx context.Context, yeyCtx yey.Context, containerName string,
 	args = append(args, yeyCtx.Image)
 	args = append(args, yeyCtx.Cmd...)
 
+	if options.dryRun {
+		fmt.Printf("docker %s\n", strings.Join(args, " "))
+		return nil
+	}
+
 	return attachStdPipes(exec.CommandContext(ctx, "docker", args...)).Run()
 }
 
-func startContainer(ctx context.Context, containerName string) error {
-	return attachStdPipes(exec.CommandContext(ctx, "docker", "start", "-i", containerName)).Run()
+func startContainer(ctx context.Context, containerName string, options runOptions) error {
+	args := []string{"start", "-i", containerName}
+	if options.dryRun {
+		fmt.Printf("docker %s\n", strings.Join(args, " "))
+		return nil
+	}
+	return attachStdPipes(exec.CommandContext(ctx, "docker", args...)).Run()
 }
 
 func execContainer(ctx context.Context, containerName string, cmd []string, options runOptions) error {
@@ -219,6 +243,10 @@ func execContainer(ctx context.Context, containerName string, cmd []string, opti
 	}
 	args = append(args, containerName)
 	args = append(args, cmd...)
+	if options.dryRun {
+		fmt.Printf("docker %s\n", strings.Join(args, " "))
+		return nil
+	}
 	return attachStdPipes(exec.CommandContext(ctx, "docker", args...)).Run()
 }