Bugfix: Agent fails to resolve digest for a locally available image for images with docker.io prefix

agent/utils/reference/reference.go

@@ -42,20 +42,14 @@ func GetDigestFromImageRef(imageRef string) digest.Digest {
 // and returns the repo digest's digest.
 func GetDigestFromRepoDigests(repoDigests []string, imageRef string) (digest.Digest, error) {
 	// Parse image reference
-	ref, err := reference.Parse(imageRef)
+	namedRef, err := reference.ParseNormalizedNamed(imageRef)
 	if err != nil {
 		return "", fmt.Errorf("failed to parse image reference '%s': %w", imageRef, err)
 	}
-	namedRef, ok := ref.(reference.Named)
-	if !ok {
-		return "", fmt.Errorf(
-			"failed to parse image reference '%s' as a named reference, it was parsed as '%v'",
-			imageRef, ref)
-	}
 
 	// Find a repo digest matching imageRef and return its digest
 	for _, repoDigest := range repoDigests {
-		repoDigestRef, err := reference.Parse(repoDigest)
+		repoDigestRef, err := reference.ParseNormalizedNamed(repoDigest)
 		if err != nil {
 			logger.Error("Error in parsing repo digest. Skipping it.", logger.Fields{
 				"repoDigest": repoDigest,

agent/utils/reference/reference_test.go

@@ -74,6 +74,38 @@ func TestGetDigestFromRepoDigests(t *testing.T) {
 			imageRef:       "alpine",
 			expectedDigest: testDigest2,
 		},
+		{
+			name: "docker.io prefix",
+			repoDigests: []string{
+				"alpine@" + testDigest2,
+			},
+			imageRef:       "docker.io/alpine",
+			expectedDigest: testDigest2,
+		},
+		{
+			name: "docker.io with library prefix",
+			repoDigests: []string{
+				"alpine@" + testDigest2,
+			},
+			imageRef:       "docker.io/library/alpine",
+			expectedDigest: testDigest2,
+		},
+		{
+			name: "docker.io with non-standard image",
+			repoDigests: []string{
+				"repo/image@" + testDigest2,
+			},
+			imageRef:       "docker.io/repo/image",
+			expectedDigest: testDigest2,
+		},
+		{
+			name: "registry-1.docker.io prefix",
+			repoDigests: []string{
+				"registry-1.docker.io/library/alpine@" + testDigest2,
+			},
+			imageRef:       "registry-1.docker.io/library/alpine",
+			expectedDigest: testDigest2,
+		},
 		{
 			name: "repo digest matching imageRef is used - ecr",
 			repoDigests: []string{
@@ -109,7 +141,7 @@ func TestGetDigestFromRepoDigests(t *testing.T) {
 		{
 			name:          "image ref not named",
 			imageRef:      "",
-			expectedError: "failed to parse image reference '': repository name must have at least one component",
+			expectedError: "failed to parse image reference '': invalid reference format",
 		},
 		{
 			name:           "invalid repo digests are skipped",