add ability to just update manifest

Signed-off-by: Avi Deitcher <avi@deitcher.net>

src/cmd/linuxkit/pkg.go

@@ -32,6 +32,10 @@ func pkg(args []string) {
 		pkgPush(args[1:])
 	case "show-tag":
 		pkgShowTag(args[1:])
+	case "manifest":
+		pkgManifest(args[1:])
+	case "index":
+		pkgIndex(args[1:])
 	default:
 		fmt.Printf("Unknown subcommand %q\n\n", args[0])
 		pkgUsage()

src/cmd/linuxkit/pkg_manifest.go

@@ -0,0 +1,50 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/linuxkit/linuxkit/src/cmd/linuxkit/pkglib"
+)
+
+func pkgManifest(args []string) {
+	pkgIndex(args)
+}
+func pkgIndex(args []string) {
+	flags := flag.NewFlagSet("pkg manifest", flag.ExitOnError)
+	flags.Usage = func() {
+		invoked := filepath.Base(os.Args[0])
+		name := "manifest"
+		fmt.Fprintf(os.Stderr, "USAGE: %s pkg %s [options] path\n\n", name, invoked)
+		fmt.Fprintf(os.Stderr, "'path' specifies the path to the package source directory.\n")
+		fmt.Fprintf(os.Stderr, "\n")
+		fmt.Fprintf(os.Stderr, "Updates the manifest in the registry for the given path based on all known platforms. If none found, no manifest created.\n")
+		flags.PrintDefaults()
+	}
+	release := flags.String("release", "", "Release the given version")
+
+	pkgs, err := pkglib.NewFromCLI(flags, args...)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "%v\n", err)
+		os.Exit(1)
+	}
+
+	var opts []pkglib.BuildOpt
+	if *release != "" {
+		opts = append(opts, pkglib.WithRelease(*release))
+	}
+
+	for _, p := range pkgs {
+		msg := fmt.Sprintf("Updating index for %q", p.Tag())
+		action := "building and pushing"
+
+		fmt.Println(msg)
+
+		if err := p.Index(opts...); err != nil {
+			fmt.Fprintf(os.Stderr, "Error %s %q: %v\n", action, p.Tag(), err)
+			os.Exit(1)
+		}
+	}
+}

src/cmd/linuxkit/pkglib/index.go

@@ -0,0 +1,50 @@
+package pkglib
+
+import (
+	"fmt"
+
+	"github.com/linuxkit/linuxkit/src/cmd/linuxkit/registry"
+	"github.com/linuxkit/linuxkit/src/cmd/linuxkit/util"
+)
+
+// Index create an index for the package tag based on all arch-specific tags in the registry.
+func (p Pkg) Index(bos ...BuildOpt) error {
+	var bo buildOpts
+	for _, fn := range bos {
+		if err := fn(&bo); err != nil {
+			return err
+		}
+	}
+	name := p.FullTag()
+
+	// Even though we may have pushed the index, we want to be sure that we have an index that includes every architecture on the registry,
+	// not just those that were in our local cache. So we use manifest-tool library to build a broad index
+	auth, err := registry.GetDockerAuth()
+	if err != nil {
+		return fmt.Errorf("failed to get auth: %v", err)
+	}
+
+	// push based on tag
+	fmt.Printf("Pushing index based on all arch-specific images in registry %s\n", name)
+	_, _, err = registry.PushManifest(name, auth)
+	if err != nil {
+		return err
+	}
+
+	// push based on release
+	if bo.release != "" {
+		relTag, err := p.ReleaseTag(bo.release)
+		if err != nil {
+			return err
+		}
+		fullRelTag := util.ReferenceExpand(relTag)
+
+		fmt.Printf("Pushing index based on all arch-specific images in registry %s\n", fullRelTag)
+		_, _, err = registry.PushManifest(fullRelTag, auth)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}