Merge pull request #6426 from nalind/iidfile

commit: always return the config digest as the image ID

Author: openshift-merge-bot[bot]

commit.go

@@ -531,6 +531,16 @@ func (b *Builder) Commit(ctx context.Context, dest types.ImageReference, options
 	if err != nil {
 		return imgID, nil, "", fmt.Errorf("computing digest of manifest of new image %q: %w", transports.ImageName(dest), err)
 	}
+	if imgID == "" {
+		parsedManifest, err := manifest.FromBlob(manifestBytes, manifest.GuessMIMEType(manifestBytes))
+		if err != nil {
+			return imgID, nil, "", fmt.Errorf("parsing written manifest to determine the image's ID: %w", err)
+		}
+		configInfo := parsedManifest.ConfigInfo()
+		if configInfo.Size > 2 && configInfo.Digest.Validate() == nil { // don't be returning a digest of "" or "{}"
+			imgID = configInfo.Digest.Encoded()
+		}
+	}
 
 	var ref reference.Canonical
 	if name := dest.DockerReference(); name != nil {

imagebuildah/executor.go

@@ -1086,7 +1086,11 @@ func (b *Executor) Build(ctx context.Context, stages imagebuilder.Stages) (image
 	}
 	logrus.Debugf("printing final image id %q", imageID)
 	if b.iidfile != "" {
-		if err = os.WriteFile(b.iidfile, []byte("sha256:"+imageID), 0o644); err != nil {
+		iid := imageID
+		if iid != "" {
+			iid = "sha256:" + iid // only prepend a digest algorithm name if we actually got a value back
+		}
+		if err = os.WriteFile(b.iidfile, []byte(iid), 0o644); err != nil {
 			return imageID, ref, fmt.Errorf("failed to write image ID to file %q: %w", b.iidfile, err)
 		}
 	} else {

tests/bud.bats

@@ -8958,3 +8958,29 @@ EOF
   run_buildah build --layers=false "${contextdir}"
   expect_output --substring /mounted/brand-new-subdir
 }
+
+@test "bud with --iidfile" {
+  target=scratch-image
+  local contextdir=${TEST_SCRATCH_DIR}/context
+  mkdir -p "${contextdir}"
+  cat > "${contextdir}"/Dockerfile <<-EOF
+  FROM scratch
+  COPY . .
+EOF
+  for layers in "--layers=true" "--layers=false" ; do
+    for destination in "dir:${TEST_SCRATCH_DIR}/dir" "oci-archive:${TEST_SCRATCH_DIR}/oci-archive" "docker-archive:${TEST_SCRATCH_DIR}/docker-archive" "oci:${TEST_SCRATCH_DIR}/oci-layout" "local" ; do
+      rm -f "${TEST_SCRATCH_DIR}"/iidfile
+      fsname="${destination#*:}" # assume : is used in a non-containers-storage name rather than a repository name + tag combination
+      if test "${fsname}" != "${destination}" ; then
+        rm -fr "${fsname}"
+      fi
+      run_buildah build --iidfile "${TEST_SCRATCH_DIR}"/iidfile --no-cache "${layers}" -t "${destination}" "${contextdir}"
+      local iid=$(cat "${TEST_SCRATCH_DIR}"/iidfile)
+      assert "${iid}" != ""
+      assert "${iid#sha256:}" != ""
+      if test "${fsname}" != "${destination}" ; then
+        test -e "${fsname}"
+      fi
+    done
+  done
+}