Feature/allow no exists helmvalues file (#1212)

Signed-off-by: William Wang <williamw0825@gmail.com>

Author: will4j

pkg/argocd/update.go

@@ -485,10 +485,27 @@ func marshalParamsOverride(app *v1alpha1.Application, originalData []byte) ([]by
 		if strings.HasPrefix(app.Annotations[common.WriteBackTargetAnnotation], common.HelmPrefix) {
 			images := GetImagesAndAliasesFromApplication(app)
 
-			helmNewValues := yaml.Node{}
-			err = yaml.Unmarshal(originalData, &helmNewValues)
-			if err != nil {
-				return nil, err
+			var helmNewValues yaml.Node
+			if len(originalData) == 0 {
+				// allow non-exists target file
+				helmNewValues = yaml.Node{
+					Kind:        yaml.DocumentNode,
+					HeadComment: "auto generated by argocd image updater",
+					Content: []*yaml.Node{
+						{
+							Kind:    yaml.MappingNode,
+							Tag:     "!!map",
+							Content: []*yaml.Node{},
+							Style:   yaml.LiteralStyle,
+						},
+					},
+				}
+			} else {
+				helmNewValues = yaml.Node{}
+				err = yaml.Unmarshal(originalData, &helmNewValues)
+				if err != nil {
+					return nil, err
+				}
 			}
 
 			for _, c := range images {

pkg/argocd/update_test.go

@@ -2166,6 +2166,52 @@ replicas: 1
 		assert.Error(t, err)
 	})
 
+	t.Run("Nil source merge for Helm source with Helm values file", func(t *testing.T) {
+		app := v1alpha1.Application{
+			ObjectMeta: v1.ObjectMeta{
+				Name: "testapp",
+				Annotations: map[string]string{
+					"argocd-image-updater.argoproj.io/image-list":            "nginx",
+					"argocd-image-updater.argoproj.io/write-back-method":     "git",
+					"argocd-image-updater.argoproj.io/write-back-target":     "helmvalues:./test-values.yaml",
+					"argocd-image-updater.argoproj.io/nginx.helm.image-name": "image.name",
+					"argocd-image-updater.argoproj.io/nginx.helm.image-tag":  "image.tag",
+				},
+			},
+			Spec: v1alpha1.ApplicationSpec{
+				Source: &v1alpha1.ApplicationSource{
+					RepoURL:        "https://example.com/example",
+					TargetRevision: "main",
+					Helm: &v1alpha1.ApplicationSourceHelm{
+						Parameters: []v1alpha1.HelmParameter{
+							{
+								Name:        "image.name",
+								Value:       "nginx",
+								ForceString: true,
+							},
+							{
+								Name:        "image.tag",
+								Value:       "v1.0.0",
+								ForceString: true,
+							},
+						},
+					},
+				},
+			},
+			Status: v1alpha1.ApplicationStatus{
+				SourceType: v1alpha1.ApplicationSourceTypeHelm,
+				Summary: v1alpha1.ApplicationSummary{
+					Images: []string{
+						"nginx:v0.0.0",
+					},
+				},
+			},
+		}
+
+		_, err := marshalParamsOverride(&app, nil)
+		assert.NoError(t, err)
+	})
+
 	t.Run("Unknown source", func(t *testing.T) {
 		app := v1alpha1.Application{
 			ObjectMeta: v1.ObjectMeta{