Add upload to Google Cloud Storage and Google Compute Image creation

- the image upload uses the cloud API
- currently auth and image creation need the `gcloud` CLI tool.

Signed-off-by: Justin Cormack <justin.cormack@docker.com>

config.go

@@ -27,6 +27,9 @@ type Moby struct {
 	}
 	Outputs []struct {
 		Format  string
+		Project string
+		Bucket  string
+		Public  bool
 	}
 }
 

gcp.go

@@ -0,0 +1,82 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"os/exec"
+
+	"cloud.google.com/go/storage"
+	"golang.org/x/net/context"
+)
+
+func uploadGS(filename, project, bucket string, public bool) error {
+	if project != "" {
+		err := os.Setenv("GOOGLE_CLOUD_PROJECT", project)
+		if err != nil {
+			return err
+		}
+	}
+	if os.Getenv("GOOGLE_CLOUD_PROJECT") == "" {
+		return errors.New("GOOGLE_CLOUD_PROJECT environment variable must be set or project specified in config")
+	}
+
+	ctx := context.Background()
+	client, err := storage.NewClient(ctx)
+	if err != nil {
+		return err
+	}
+
+	f, err := os.Open(filename)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	wc := client.Bucket(bucket).Object(filename).NewWriter(ctx)
+	_, err = io.Copy(wc, f)
+	if err != nil {
+		return err
+	}
+	err = wc.Close()
+	if err != nil {
+		return err
+	}
+
+	// TODO make public if requested
+
+	fmt.Println("gs://" + bucket + "/" + filename)
+
+	return nil
+}
+
+func imageGS(filename, project, storage string) error {
+	if project != "" {
+		err := os.Setenv("GOOGLE_CLOUD_PROJECT", project)
+		if err != nil {
+			return err
+		}
+	}
+	if os.Getenv("GOOGLE_CLOUD_PROJECT") == "" {
+		return errors.New("GOOGLE_CLOUD_PROJECT environment variable must be set or project specified in config")
+	}
+
+	// TODO do not shell out to gcloud tool, use the API
+
+	gcloud, err := exec.LookPath("gcloud")
+	if err != nil {
+		return errors.New("Please install the gcloud binary")
+	}
+	args := []string{"compute", "images", "create", "--source-uri", storage, filename}
+	cmd := exec.Command(gcloud, args...)
+
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		return fmt.Errorf("Image creation failed: %v - %s", err, string(out))
+	}
+
+	fmt.Println(filename)
+
+	return nil
+}

output.go

@@ -39,6 +39,34 @@ func outputs(m *Moby, base string, bzimage []byte, initrd []byte) error {
 			if err != nil {
 				return fmt.Errorf("Error writing %s output: %v", o.Format, err)
 			}
+		case "gce-storage":
+			err := outputImg(gce, base+".img.tar.gz", bzimage, initrd, m.Kernel.Cmdline)
+			if err != nil {
+				return fmt.Errorf("Error writing %s output: %v", o.Format, err)
+			}
+			if o.Bucket == "" {
+				return fmt.Errorf("No bucket specified for GCE output")
+			}
+			err = uploadGS(base+".img.tar.gz", o.Project, o.Bucket, o.Public)
+			if err != nil {
+				return fmt.Errorf("Error copying to Google Storage: %v", err)
+			}
+		case "gce":
+			err := outputImg(gce, base+".img.tar.gz", bzimage, initrd, m.Kernel.Cmdline)
+			if err != nil {
+				return fmt.Errorf("Error writing %s output: %v", o.Format, err)
+			}
+			if o.Bucket == "" {
+				return fmt.Errorf("No bucket specified for GCE output")
+			}
+			err = uploadGS(base+".img.tar.gz", o.Project, o.Bucket, o.Public)
+			if err != nil {
+				return fmt.Errorf("Error copying to Google Storage: %v", err)
+			}
+			err = imageGS(base, o.Project, "https://storage.googleapis.com/"+o.Bucket+"/"+base+".img.tar.gz")
+			if err != nil {
+				return fmt.Errorf("Error creating Google Compute Image: %v", err)
+			}
 		case "qcow", "qcow2":
 			err := outputImg(qcow, base+".qcow2", bzimage, initrd, m.Kernel.Cmdline)
 			if err != nil {