fix: missing digests on manifests (#3602)

it was missing the digest parsing for the manifest, and there were no
tests covering it.

now the tests are there, and so is the fix.

refs #3599

internal/pipe/docker/api.go

@@ -40,7 +40,7 @@ type imager interface {
 // manifester is something that can create and push docker manifests.
 type manifester interface {
 	Create(ctx *context.Context, manifest string, images, flags []string) error
-	Push(ctx *context.Context, manifest string, flags []string) error
+	Push(ctx *context.Context, manifest string, flags []string) (digest string, err error)
 }
 
 // nolint: unparam

internal/pipe/docker/api_docker.go

@@ -31,13 +31,18 @@ func (m dockerManifester) Create(ctx *context.Context, manifest string, images,
 	return nil
 }
 
-func (m dockerManifester) Push(ctx *context.Context, manifest string, flags []string) error {
+func (m dockerManifester) Push(ctx *context.Context, manifest string, flags []string) (string, error) {
 	args := []string{"manifest", "push", manifest}
 	args = append(args, flags...)
-	if err := runCommand(ctx, ".", "docker", args...); err != nil {
-		return fmt.Errorf("failed to push %s: %w", manifest, err)
+	bts, err := runCommandWithOutput(ctx, ".", "docker", args...)
+	if err != nil {
+		return "", fmt.Errorf("failed to push %s: %w", manifest, err)
 	}
-	return nil
+	digest := dockerDigestPattern.FindString(string(bts))
+	if digest == "" {
+		return "", fmt.Errorf("failed to find docker digest in docker push output: %s", string(bts))
+	}
+	return digest, nil
 }
 
 type dockerImager struct {
@@ -46,18 +51,15 @@ type dockerImager struct {
 
 var dockerDigestPattern = regexp.MustCompile("sha256:[a-z0-9]{64}")
 
-func (i dockerImager) Push(ctx *context.Context, image string, flags []string) (digest string, err error) {
-	outBytes, err := runCommandWithOutput(ctx, ".", "docker", "push", image)
+func (i dockerImager) Push(ctx *context.Context, image string, flags []string) (string, error) {
+	bts, err := runCommandWithOutput(ctx, ".", "docker", "push", image)
 	if err != nil {
 		return "", fmt.Errorf("failed to push %s: %w", image, err)
 	}
-
-	out := string(outBytes)
-	digest = dockerDigestPattern.FindString(out)
+	digest := dockerDigestPattern.FindString(string(bts))
 	if digest == "" {
-		return "", fmt.Errorf("failed to find docker digest in docker push output: %v", out)
+		return "", fmt.Errorf("failed to find docker digest in docker push output: %s", string(bts))
 	}
-
 	return digest, nil
 }
 

internal/pipe/docker/docker_test.go

@@ -1093,10 +1093,15 @@ func TestRunPipe(t *testing.T) {
 					require.NoError(t, rmi(img), "could not delete image %s", img)
 				}
 
-				_ = ctx.Artifacts.Filter(artifact.ByType(artifact.DockerImage)).Visit(func(a *artifact.Artifact) error {
+				_ = ctx.Artifacts.Filter(
+					artifact.Or(
+						artifact.ByType(artifact.DockerImage),
+						artifact.ByType(artifact.DockerManifest),
+					),
+				).Visit(func(a *artifact.Artifact) error {
 					digest, err := artifact.Extra[string](*a, artifact.ExtraDigest)
 					require.NoError(t, err)
-					require.NotEmpty(t, digest)
+					require.NotEmpty(t, digest, "missing digest for "+a.Name)
 					return nil
 				})
 			})

internal/pipe/docker/manifest.go

@@ -81,10 +81,15 @@ func (ManifestPipe) Publish(ctx *context.Context) error {
 			if manifest.ID != "" {
 				art.Extra[artifact.ExtraID] = manifest.ID
 			}
-			ctx.Artifacts.Add(art)
 
 			log.WithField("manifest", name).Info("pushing")
-			return manifester.Push(ctx, name, manifest.PushFlags)
+			digest, err := manifester.Push(ctx, name, manifest.PushFlags)
+			if err != nil {
+				return err
+			}
+			art.Extra[artifact.ExtraDigest] = digest
+			ctx.Artifacts.Add(art)
+			return nil
 		})
 	}
 	return g.Wait()