mantle/ore: gcloud: add promote-image command

In our build/release workflow for GCP we build and upload/create
a GCP image in the build pipeline. We deprecate the image (because
we haven't decided to release it yet) and then add it to the
corresponding image family for the stream it was built against.

The promote-image command will be used in the release pipeline to
undeprecate the image now that we have decided to release it. Since
we only want one image visible in an image family at any given time,
the promote-image command will then deprecate all other images in
the specified image family.

mantle/cmd/ore/gcloud/promote-image.go

@@ -0,0 +1,113 @@
+// Copyright 2020 Red Hat
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package gcloud
+
+import (
+	"github.com/coreos/mantle/platform/api/gcloud"
+	"github.com/spf13/cobra"
+	"golang.org/x/net/context"
+)
+
+var (
+	cmdPromoteImage = &cobra.Command{
+		Use:   "promote-image",
+		Short: "Promote GCP image in image family",
+		Long:  "Promote GCP image in image family and deprecate all others",
+		Run:   runPromoteImage,
+	}
+
+	promoteImageName   string
+	promoteImageFamily string
+)
+
+func init() {
+	cmdPromoteImage.Flags().StringVar(&promoteImageName, "image", "", "GCP image name")
+	cmdPromoteImage.Flags().StringVar(&promoteImageFamily, "family", "", "GCP image family to promote within")
+	GCloud.AddCommand(cmdPromoteImage)
+}
+
+func deprecateImage(name string, state gcloud.DeprecationState, replacement string) {
+	plog.Infof("Changing deprecation state of image: %v -> %v", name, state)
+	pending, err := api.DeprecateImage(name, state, replacement)
+	if err == nil {
+		err = pending.Wait()
+	}
+	// New if statement to check err on api.DeprecateImage or pending.Wait()
+	if err != nil {
+		plog.Fatalf("Changing deprecation state of image failed: %v\n", err)
+	}
+}
+
+func runPromoteImage(cmd *cobra.Command, args []string) {
+	// Check that the user provided an image
+	if promoteImageName == "" {
+		plog.Fatal("Must provide an image name via --image")
+	}
+	// Check that the user provided an image family
+	if promoteImageFamily == "" {
+		plog.Fatal("Must provide an image family via --family")
+	}
+
+	plog.Infof("Attempting to promote %v in family %v",
+		promoteImageName, promoteImageFamily)
+
+	// Get all images in the image family
+	images, err := api.ListImages(context.Background(), "", promoteImageFamily)
+	if err != nil {
+		plog.Fatal(err)
+	}
+
+	// Make sure the specified image exists in the specified image family
+	found := false
+	for _, image := range images {
+		if image.Name == promoteImageName {
+			found = true
+		}
+	}
+	if !found {
+		plog.Fatalf("The image (%v) must be in the image family (%v)",
+			promoteImageName, promoteImageFamily)
+	}
+
+	// First undeprecate the image we want to promote
+	deprecateImage(promoteImageName, gcloud.DeprecationStateActive, "")
+
+	// Next deprecate all other images in the image family
+	// that need to be deprecated.
+	for _, image := range images {
+		// don't deprecate the image we just undeprecated
+		if image.Name == promoteImageName {
+			continue
+		}
+		// Some debug messages which are useful when needed.
+		if image.Deprecated != nil {
+			plog.Debugf("Deprecation state for %v is %v",
+				image.Name, image.Deprecated.State)
+		} else {
+			plog.Debugf("Deprecation state is nil for %v", image.Name)
+		}
+		// Perform the deprecation if the image is not already deprecated.
+		// We detect if it is active by checking if it either doesn't
+		// have any deprecation state or if it is explicitly ACTIVE.
+		if image.Deprecated == nil ||
+			image.Deprecated.State == string(gcloud.DeprecationStateActive) {
+			deprecateImage(
+				image.Name,
+				gcloud.DeprecationStateDeprecated,
+				promoteImageName,
+			)
+		}
+	}
+}