refactor: move git write-back source logic to git.go && remove e2e tests && enhance unit tests

Signed-off-by: Atif Ali <atali@redhat.com>

Author: aali309

pkg/argocd/argocd.go

@@ -675,34 +675,17 @@ func getApplicationSourceType(app *v1alpha1.Application) v1alpha1.ApplicationSou
 	return app.Status.SourceType
 }
 
-// getApplicationSource returns the source matching git-repository annotation
-// or the Helm/Kustomize source, or the primary source if no match is found
+// getApplicationSource returns the main source of a Helm or Kustomize type of the application
 func getApplicationSource(app *v1alpha1.Application) *v1alpha1.ApplicationSource {
-	// Get the git repository from annotations for write-back
-	gitRepo := app.Annotations["argocd-image-updater.argoproj.io/git-repository"]
-	logCtx := log.WithContext().AddField("application", app.GetName())
 
 	if app.Spec.HasMultipleSources() {
-		// If we have a specific git repo configured for write-back
-		if gitRepo != "" {
-			// Try to find the source matching the write-back git repository
-			for _, s := range app.Spec.Sources {
-				if s.RepoURL == gitRepo {
-					logCtx.Debugf("Found matching source for git repository %s", gitRepo)
-					return &s
-				}
-			}
-			logCtx.Debugf("No matching source found for git repository %s", gitRepo)
-		}
-
-		// If no git repo match, check for Helm/Kustomize sources
 		for _, s := range app.Spec.Sources {
 			if s.Helm != nil || s.Kustomize != nil {
 				return &s
 			}
 		}
 
-		logCtx.Tracef("Could not get Source of type Helm or Kustomize from multisource configuration. Returning first source from the list")
+		log.WithContext().AddField("application", app.GetName()).Tracef("Could not get Source of type Helm or Kustomize from multisource configuration. Returning first source from the list")
 		return &app.Spec.Sources[0]
 	}
 

pkg/argocd/git.go

@@ -17,6 +17,7 @@ import (
 	"sigs.k8s.io/kustomize/kyaml/order"
 	kyaml "sigs.k8s.io/kustomize/kyaml/yaml"
 
+	"github.com/argoproj-labs/argocd-image-updater/pkg/common"
 	"github.com/argoproj-labs/argocd-image-updater/registry-scanner/pkg/image"
 
 	"github.com/argoproj-labs/argocd-image-updater/ext/git"
@@ -128,6 +129,36 @@ func TemplateBranchName(branchName string, changeList []ChangeEntry) string {
 
 type changeWriter func(app *v1alpha1.Application, wbc *WriteBackConfig, gitC git.Client) (err error, skip bool)
 
+// getWriteBackBranch returns the branch to use for write-back operations.
+// It first checks for a branch specified in annotations, then uses the
+// targetRevision from the matching git source, falling back to getApplicationSource.
+func getWriteBackBranch(app *v1alpha1.Application) string {
+	// First check if branch is explicitly set in annotations
+	annotations := app.GetAnnotations()
+	if branch, ok := annotations[common.GitBranchAnnotation]; ok {
+		return branch
+	}
+
+	logCtx := log.WithContext().AddField("application", app.GetName())
+
+	// If git repository is specified, find matching source
+	if gitRepo, ok := annotations[common.GitRepositoryAnnotation]; ok {
+		if app.Spec.HasMultipleSources() {
+			for _, s := range app.Spec.Sources {
+				if s.RepoURL == gitRepo {
+					logCtx.Debugf("Found matching source for git repository %s", gitRepo)
+					return s.TargetRevision
+				}
+			}
+			logCtx.Debugf("No matching source found for git repository %s, falling back to getApplicationSource", gitRepo)
+		}
+	}
+
+	// Fall back to getApplicationSource's targetRevision
+	// This maintains consistency with how other parts of the code select the source
+	return getApplicationSource(app).TargetRevision
+}
+
 // commitChanges commits any changes required for updating one or more images
 // after the UpdateApplication cycle has finished.
 func commitChangesGit(app *v1alpha1.Application, wbc *WriteBackConfig, changeList []ChangeEntry, write changeWriter) error {
@@ -164,7 +195,7 @@ func commitChangesGit(app *v1alpha1.Application, wbc *WriteBackConfig, changeLis
 	// config, or taken from the application spec's targetRevision. If the
 	// target revision is set to the special value HEAD, or is the empty
 	// string, we'll try to resolve it to a branch name.
-	checkOutBranch := getApplicationSource(app).TargetRevision
+	checkOutBranch := getWriteBackBranch(app)
 	if wbc.GitBranch != "" {
 		checkOutBranch = wbc.GitBranch
 	}

pkg/argocd/git_test.go

@@ -333,7 +333,67 @@ func Test_updateKustomizeFile(t *testing.T) {
 }
 
 func Test_getApplicationSource(t *testing.T) {
-	t.Run("multi-source with matching git repo", func(t *testing.T) {
+	t.Run("multi-source without git repo annotation", func(t *testing.T) {
+		app := &v1alpha1.Application{
+			ObjectMeta: v1.ObjectMeta{
+				Name: "test-app",
+			},
+			Spec: v1alpha1.ApplicationSpec{
+				Sources: v1alpha1.ApplicationSources{
+					{
+						RepoURL:        "https://charts.bitnami.com/bitnami",
+						TargetRevision: "18.2.3",
+						Chart:          "nginx",
+						Helm:           &v1alpha1.ApplicationSourceHelm{},
+					},
+					{
+						RepoURL:        "https://github.com/chengfang/image-updater-examples.git",
+						TargetRevision: "main",
+					},
+				},
+			},
+		}
+
+		source := getApplicationSource(app)
+		assert.Equal(t, "18.2.3", source.TargetRevision)
+		assert.Equal(t, "https://charts.bitnami.com/bitnami", source.RepoURL)
+	})
+
+	t.Run("single source application", func(t *testing.T) {
+		app := &v1alpha1.Application{
+			ObjectMeta: v1.ObjectMeta{
+				Name: "test-app",
+			},
+			Spec: v1alpha1.ApplicationSpec{
+				Source: &v1alpha1.ApplicationSource{
+					RepoURL:        "https://github.com/example/repo.git",
+					TargetRevision: "main",
+				},
+			},
+		}
+
+		source := getApplicationSource(app)
+		assert.Equal(t, "main", source.TargetRevision)
+		assert.Equal(t, "https://github.com/example/repo.git", source.RepoURL)
+	})
+}
+
+func Test_getWriteBackBranch(t *testing.T) {
+	t.Run("explicit branch in annotations", func(t *testing.T) {
+		app := &v1alpha1.Application{
+			ObjectMeta: v1.ObjectMeta{
+				Name: "test-app",
+				Annotations: map[string]string{
+					"argocd-image-updater.argoproj.io/git-branch": "custom-branch",
+				},
+			},
+		}
+
+		branch := getWriteBackBranch(app)
+		assert.Equal(t, "custom-branch", branch)
+	})
+
+	t.Run("matching git-repository annotation", func(t *testing.T) {
 		app := &v1alpha1.Application{
 			ObjectMeta: v1.ObjectMeta{
 				Name: "test-app",
@@ -356,12 +416,11 @@ func Test_getApplicationSource(t *testing.T) {
 			},
 		}
 
-		source := getApplicationSource(app)
-		assert.Equal(t, "main", source.TargetRevision)
-		assert.Equal(t, "https://github.com/chengfang/image-updater-examples.git", source.RepoURL)
+		branch := getWriteBackBranch(app)
+		assert.Equal(t, "main", branch)
 	})
 
-	t.Run("multi-source without git repo annotation", func(t *testing.T) {
+	t.Run("fallback to primary source when no match", func(t *testing.T) {
 		app := &v1alpha1.Application{
 			ObjectMeta: v1.ObjectMeta{
 				Name: "test-app",
@@ -382,26 +441,31 @@ func Test_getApplicationSource(t *testing.T) {
 			},
 		}
 
-		source := getApplicationSource(app)
-		assert.Equal(t, "18.2.3", source.TargetRevision)
-		assert.Equal(t, "https://charts.bitnami.com/bitnami", source.RepoURL)
+		branch := getWriteBackBranch(app)
+		assert.Equal(t, "18.2.3", branch)
 	})
 
-	t.Run("single source application", func(t *testing.T) {
+	t.Run("git-repository annotation with non-matching URL", func(t *testing.T) {
 		app := &v1alpha1.Application{
 			ObjectMeta: v1.ObjectMeta{
 				Name: "test-app",
+				Annotations: map[string]string{
+					"argocd-image-updater.argoproj.io/git-repository": "https://github.com/different/repo.git",
+				},
 			},
 			Spec: v1alpha1.ApplicationSpec{
-				Source: &v1alpha1.ApplicationSource{
-					RepoURL:        "https://github.com/example/repo.git",
-					TargetRevision: "main",
+				Sources: v1alpha1.ApplicationSources{
+					{
+						RepoURL:        "https://charts.bitnami.com/bitnami",
+						TargetRevision: "18.2.3",
+						Chart:          "nginx",
+						Helm:           &v1alpha1.ApplicationSourceHelm{},
+					},
 				},
 			},
 		}
 
-		source := getApplicationSource(app)
-		assert.Equal(t, "main", source.TargetRevision)
-		assert.Equal(t, "https://github.com/example/repo.git", source.RepoURL)
+		branch := getWriteBackBranch(app)
+		assert.Equal(t, "18.2.3", branch)
 	})
 }