Merge pull request docker#105 from nathanleclaire/cache_b2d_iso

Only download boot2docker.iso one time

drivers/virtualbox/virtualbox.go

@@ -97,6 +97,17 @@ func (d *Driver) SetConfigFromFlags(flags drivers.DriverOptions) error {
 	return nil
 }
 
+func cpIso(src, dest string) error {
+	buf, err := ioutil.ReadFile(src)
+	if err != nil {
+		return err
+	}
+	if err := ioutil.WriteFile(dest, buf, 0600); err != nil {
+		return err
+	}
+	return nil
+}
+
 func (d *Driver) Create() error {
 	var (
 		err    error
@@ -116,17 +127,45 @@ func (d *Driver) Create() error {
 
 	if d.Boot2DockerURL != "" {
 		isoURL = d.Boot2DockerURL
+		log.Infof("Downloading boot2docker.iso from %s...", isoURL)
+		if err := downloadISO(d.storePath, "boot2docker.iso", isoURL); err != nil {
+			return err
+		}
 	} else {
 		// HACK: Docker 1.3 boot2docker image with client/daemon auth
 		isoURL = "https://bfirsh.s3.amazonaws.com/boot2docker/boot2docker-1.3.1-identity-auth.iso"
+
+		// todo: check latest release URL, download if it's new
+		// until then always use "latest"
+
 		// isoURL, err = getLatestReleaseURL()
 		// if err != nil {
 		// 	return err
 		// }
-	}
-	log.Infof("Downloading boot2docker...")
-	if err := downloadISO(d.storePath, "boot2docker.iso", isoURL); err != nil {
-		return err
+
+		// todo: use real constant for .docker
+		rootPath := filepath.Join(drivers.GetHomeDir(), ".docker")
+		imgPath := filepath.Join(rootPath, "images")
+		commonIsoPath := filepath.Join(imgPath, "boot2docker.iso")
+		if _, err := os.Stat(commonIsoPath); os.IsNotExist(err) {
+			log.Infof("Downloading boot2docker.iso to %s...", commonIsoPath)
+
+			// just in case boot2docker.iso has been manually deleted
+			if _, err := os.Stat(imgPath); os.IsNotExist(err) {
+				if err := os.Mkdir(imgPath, 0700); err != nil {
+					return err
+				}
+			}
+
+			if err := downloadISO(imgPath, "boot2docker.iso", isoURL); err != nil {
+				return err
+			}
+		}
+
+		isoDest := filepath.Join(d.storePath, "boot2docker.iso")
+		if err := cpIso(commonIsoPath, isoDest); err != nil {
+			return err
+		}
 	}
 
 	log.Infof("Creating SSH key...")