Return digest property from image name parser

image.Split now returns 3 fields: name, tag, and digest. The tag and digest
fields no longer include their respective delimiters (`:` and `@`).

api/filters/imagetag/imagetag_test.go

@@ -687,6 +687,37 @@ spec:
 				},
 			},
 		},
+		"new tag and digest": {
+			input: `
+apiVersion: example.com/v1
+kind: Foo
+metadata:
+  name: instance
+spec:
+  image: nginx:1.2.1@sha256:46d5b90a7f4e9996351ad893a26bcbd27216676ad4d5316088ce351fb2c2c3dd
+`,
+			expectedOutput: `
+apiVersion: example.com/v1
+kind: Foo
+metadata:
+  name: instance
+spec:
+  image: apache:1.3.0@sha256:xyz
+`,
+			filter: Filter{
+				ImageTag: types.Image{
+					Name:    "nginx",
+					NewName: "apache",
+					NewTag:  "1.3.0",
+					Digest:  "sha256:xyz",
+				},
+			},
+			fsSlice: []types.FieldSpec{
+				{
+					Path: "spec/image",
+				},
+			},
+		},
 	}
 
 	for tn, tc := range testCases {

api/filters/imagetag/updater.go

@@ -28,14 +28,25 @@ func (u imageTagUpdater) Filter(rn *yaml.RNode) (*yaml.RNode, error) {
 		return rn, nil
 	}
 
-	name, tag := image.Split(value)
+	name, tag, digest := image.Split(value)
 	if u.ImageTag.NewName != "" {
 		name = u.ImageTag.NewName
 	}
-	if u.ImageTag.NewTag != "" {
-		tag = ":" + u.ImageTag.NewTag
+	// not overriding tag/digest component, keep original
+	if u.ImageTag.NewTag == "" && u.ImageTag.Digest == "" {
+		if tag != "" {
+			tag = ":" + tag
+		}
+		if digest != "" {
+			tag += "@" + digest
+		}
 	}
-	if u.ImageTag.Digest != "" {
+	// overriding tag or digest will replace both original tag and digest values
+	if u.ImageTag.NewTag != "" && u.ImageTag.Digest != "" {
+		tag = ":" + u.ImageTag.NewTag + "@" + u.ImageTag.Digest
+	} else if u.ImageTag.NewTag != "" {
+		tag = ":" + u.ImageTag.NewTag
+	} else if u.ImageTag.Digest != "" {
 		tag = "@" + u.ImageTag.Digest
 	}
 

api/image/image.go

@@ -20,38 +20,47 @@ func IsImageMatched(s, t string) bool {
 
 // Split separates and returns the name and tag parts
 // from the image string using either colon `:` or at `@` separators.
-// Note that the returned tag keeps its separator.
-func Split(imageName string) (name string, tag string) {
+// image reference pattern: [[host[:port]/]component/]component[:tag][@digest]
+func Split(imageName string) (name string, tag string, digest string) {
 	// check if image name contains a domain
 	// if domain is present, ignore domain and check for `:`
 	searchName := imageName
 	slashIndex := strings.Index(imageName, "/")
 	if slashIndex > 0 {
 		searchName = imageName[slashIndex:]
+	} else {
+		slashIndex = 0
 	}
 
-	i := strings.LastIndex(imageName, "@")
-	if i > 0 {
-		ic := strings.Index(searchName[:i], ":")
-		if ic > 0 {
-			if slashIndex > 0 {
-				i = slashIndex + ic
-			} else {
-				i = ic
-			}
-		}
-	} else {
-		i = strings.LastIndex(searchName, ":")
-		if i > 0 && slashIndex > 0 {
-			i = slashIndex + i
-		}
+	id := strings.Index(searchName, "@")
+	ic := strings.Index(searchName, ":")
+
+	// no tag or digest
+	if ic < 0 && id < 0 {
+		return imageName, "", ""
+	}
+
+	// digest only
+	if id >= 0 && (id < ic || ic < 0) {
+		id += slashIndex
+		name = imageName[:id]
+		digest = strings.TrimPrefix(imageName[id:], "@")
+		return name, "", digest
 	}
 
-	if i < 0 {
-		return imageName, ""
+	// tag and digest
+	if id >= 0 && ic >= 0 {
+		id += slashIndex
+		ic += slashIndex
+		name = imageName[:ic]
+		tag = strings.TrimPrefix(imageName[ic:id], ":")
+		digest = strings.TrimPrefix(imageName[id:], "@")
+		return name, tag, digest
 	}
 
-	name = imageName[:i]
-	tag = imageName[i:]
-	return
+	// tag only
+	ic += slashIndex
+	name = imageName[:ic]
+	tag = strings.TrimPrefix(imageName[ic:], ":")
+	return name, tag, ""
 }

api/image/image_test.go

@@ -61,50 +61,65 @@ func TestSplit(t *testing.T) {
 		value    string
 		name     string
 		tag      string
+		digest   string
 	}{
 		{
 			testName: "no tag",
 			value:    "nginx",
 			name:     "nginx",
 			tag:      "",
+			digest:   "",
 		},
 		{
 			testName: "with tag",
 			value:    "nginx:1.2.3",
 			name:     "nginx",
-			tag:      ":1.2.3",
+			tag:      "1.2.3",
+			digest:   "",
 		},
 		{
 			testName: "with digest",
 			value:    "nginx@sha256:12345",
 			name:     "nginx",
-			tag:      "@sha256:12345",
+			tag:      "",
+			digest:   "sha256:12345",
 		},
 		{
 			testName: "with tag and digest",
 			value:    "nginx:1.2.3@sha256:12345",
 			name:     "nginx",
-			tag:      ":1.2.3@sha256:12345",
+			tag:      "1.2.3",
+			digest:   "sha256:12345",
 		},
 		{
 			testName: "with domain",
 			value:    "docker.io/nginx:1.2.3",
 			name:     "docker.io/nginx",
-			tag:      ":1.2.3",
+			tag:      "1.2.3",
+			digest:   "",
 		},
 		{
 			testName: "with domain and port",
 			value:    "foo.com:443/nginx:1.2.3",
 			name:     "foo.com:443/nginx",
-			tag:      ":1.2.3",
+			tag:      "1.2.3",
+			digest:   "",
+		},
+		{
+			testName: "with domain, port, and digest",
+			value:    "foo.com:443/nginx:1.2.3@sha256:12345",
+			name:     "foo.com:443/nginx",
+			tag:      "1.2.3",
+			digest:   "sha256:12345",
 		},
 	}
 
 	for _, tc := range testCases {
 		t.Run(tc.testName, func(t *testing.T) {
-			name, tag := Split(tc.value)
+			name, tag, digest := Split(tc.value)
 			assert.Equal(t, tc.name, name)
 			assert.Equal(t, tc.tag, tag)
+			assert.Equal(t, tc.digest, digest)
 		})
 	}
 }