Start adding cli options

Author: clareliguori

README.md

@@ -8,8 +8,10 @@ docker build -t lambda-php .
 docker run lambda-php hello '{"name": "World"}'
 
 docker run lambda-php goodbye '{"name": "World"}'
+
+../../bin/img2lambda -i docker-daemon:lambda-php:latest
 ```
 
 ## License Summary
 
-This sample code is made available under a modified MIT license. See the LICENSE file.
+This sample code is made available under a modified MIT license. See the LICENSE file.

main.go

@@ -1,14 +1,72 @@
 package main
 
 import (
-	"fmt"
+	"log"
 	"os"
+
+	"github.com/urfave/cli"
 )
 
+type cmdOptions struct {
+	image          string // Name of the container image
+	region         string // AWS region
+	outputDir      string // Output directory for the Lambda layers
+	dryRun         bool   // Dry-run (will not register with Lambda)
+	layerNamespace string // Prefix for published Lambda layers
+}
+
+func createApp() (*cli.App, *cmdOptions) {
+	opts := cmdOptions{}
+
+	app := cli.NewApp()
+	app.EnableBashCompletion = true
+	app.Name = "img2lambda"
+	app.Usage = "Repackages a container image into Lambda layers and publishes them to Lambda"
+	app.Action = func(c *cli.Context) error {
+		return repackImageAction(&opts)
+	}
+	app.Flags = []cli.Flag{
+		cli.StringFlag{
+			Name:        "image, i",
+			Usage:       "Name of the source container image. Format is 'transport:details', such as 'docker-daemon:my-docker-image:latest",
+			Destination: &opts.image,
+		},
+		cli.StringFlag{
+			Name:        "region, r",
+			Usage:       "AWS region",
+			Value:       "us-east-1",
+			Destination: &opts.region,
+		},
+		cli.StringFlag{
+			Name:        "output-directory, o",
+			Usage:       "Destination directory for command output",
+			Value:       "./output",
+			Destination: &opts.outputDir,
+		},
+		cli.StringFlag{
+			Name:        "layer-namespace, n",
+			Usage:       "Prefix for the layers published to Lambda",
+			Value:       "img2lambda",
+			Destination: &opts.layerNamespace,
+		},
+		cli.BoolFlag{
+			Name:        "dry-run, d",
+			Usage:       "Conduct a dry-run: Repackage the image, but write the Lambda layers to local disk (do not publish to Lambda)",
+			Destination: &opts.dryRun,
+		},
+	}
+	return app, &opts
+}
+
+func repackImageAction(opts *cmdOptions) error {
+	return RepackImage(opts.image)
+}
+
 func main() {
-	err := RepackImage("docker-daemon:lambda-php:latest")
+	app, _ := createApp()
+	err := app.Run(os.Args)
 	if err != nil {
-		fmt.Printf("Error: %+v", err)
+		log.Fatal(err)
 		os.Exit(1)
 	}
 }