Repository: shini4i/argo-watcher (go)

Issue:
updater: support argo-cd applications with multiple sources
Currently argo-watcher updater supports direct commit integration with argo-cd applications with single source.

Since argo-cd version 2.6+ has the ability to specify multiple sources for a single Application.

Pull request description:
feat(updater): add support for multi source applications
When merged, it will close #224 

Patch:
diff --git a/docs/git-integration.md b/docs/git-integration.md
index b5c24b2..a6b4e35 100644
--- a/docs/git-integration.md
+++ b/docs/git-integration.md
@@ -58,6 +58,23 @@ argo-watcher/managed-images: "app=registry.example.com/group-name/project-name"
 argo-watcher/app.helm.image-tag: "app.image.tag"
 ```
 
+### Multi source Applications
+
+As ArgoCD now supports an array of sources, Argo-Watcher can also work with them. But in less dynamic way. You need to add more annotations to the application:
+
+```yaml
+argo-watcher/write-back-repo: "git@github.com:example/gitops.git"
+argo-watcher/write-back-branch: "main"
+argo-watcher/write-back-path: "sandbox/charts/demo"
+```
+
+Assuming that our application name is `Demo`, argo-watcher will create/update the following override file:
+```bash
+sandbox/charts/demo/.argocd-source-demo.yaml
+```
+
+> This is not an ideal solution, but so far it is the only way to reliably determine the correct override file to update.
+
 ### Additional information
 
 - The `app` alias is intended to correspond with an alias specified in the `argo-watcher/ALIAS.helm.image-tag` annotation.
diff --git a/internal/models/argo.go b/internal/models/argo.go
index f65aa3f..6830333 100644
--- a/internal/models/argo.go
+++ b/internal/models/argo.go
@@ -21,6 +21,9 @@ const (
 	managedAnnotation       = "argo-watcher/managed"
 	managedImagesAnnotation = "argo-watcher/managed-images"
 	managedImageTagPattern  = "argo-watcher/%s.helm.image-tag"
+	managedGitRepo          = "argo-watcher/write-back-repo"
+	managedGitBranch        = "argo-watcher/write-back-branch"
+	managedGitPath          = "argo-watcher/write-back-path"
 )
 
 type ApplicationOperationResource struct {
@@ -45,36 +48,47 @@ type ApplicationResource struct {
 }
 
 type Application struct {
-	Metadata struct {
-		Name        string            `json:"name"`
-		Annotations map[string]string `json:"annotations"`
+	Metadata ApplicationMetadata `json:"metadata"`
+	Spec     ApplicationSpec     `json:"spec"`
+	Status   ApplicationStatus   `json:"status"`
+}
+
+type ApplicationStatus struct {
+	Health struct {
+		Status string `json:"status"`
 	}
-	Spec struct {
-		Source struct {
-			RepoURL        string `json:"repoURL"`
-			TargetRevision string `json:"targetRevision"`
-			Path           string `json:"path"`
-		}
+	OperationState ApplicationStatusOperationState `json:"operationState"`
+	Resources      []ApplicationResource           `json:"resources"`
+	Summary        struct {
+		Images []string `json:"images"`
+	}
+	Sync struct {
+		Status string `json:"status"`
 	}
-	Status struct {
-		Health struct {
-			Status string `json:"status"`
-		}
-		OperationState struct {
-			Phase      string `json:"phase"`
-			Message    string `json:"message"`
-			SyncResult struct {
-				Resources []ApplicationOperationResource `json:"resources"`
-			} `json:"syncResult"`
-		} `json:"operationState"`
-		Resources []ApplicationResource `json:"resources"`
-		Summary   struct {
-			Images []string `json:"images"`
-		}
-		Sync struct {
-			Status string `json:"status"`
-		}
-	} `json:"status"`
+}
+
+type ApplicationStatusOperationState struct {
+	Phase      string `json:"phase"`
+	Message    string `json:"message"`
+	SyncResult struct {
+		Resources []ApplicationOperationResource `json:"resources"`
+	} `json:"syncResult"`
+}
+
+type ApplicationMetadata struct {
+	Name        string            `json:"name"`
+	Annotations map[string]string `json:"annotations"`
+}
+
+type ApplicationSpec struct {
+	Source  ApplicationSource   `json:"source"`
+	Sources []ApplicationSource `json:"sources"`
+}
+
+type ApplicationSource struct {
+	RepoURL        string `json:"repoURL"`
+	TargetRevision string `json:"targetRevision"`
+	Path           string `json:"path"`
 }
 
 // GetRolloutStatus calculates application rollout status depending on the expected images and proxy configuration.
@@ -203,7 +217,7 @@ func (app *Application) IsManagedByWatcher() bool {
 	return app.Metadata.Annotations[managedAnnotation] == "true"
 }
 
-func (app *Application) processAppAnnotations(annotations map[string]string, task *Task) (*updater.ArgoOverrideFile, error) {
+func (app *Application) generateOverrideFileContent(annotations map[string]string, task *Task) (*updater.ArgoOverrideFile, error) {
 	overrideFileContent := updater.ArgoOverrideFile{}
 	managedImages, err := extractManagedImages(annotations)
 	if err != nil {
@@ -235,13 +249,18 @@ func (app *Application) processAppAnnotations(annotations map[string]string, tas
 }
 
 func (app *Application) UpdateGitImageTag(task *Task) error {
-	if app.Spec.Source.Path == "" {
+	gitopsRepo, err := NewGitopsRepo(app)
+	if err != nil {
+		return err
+	}
+
+	if gitopsRepo.Path == "" {
 		log.Warn().Str("id", task.Id).Msgf("No path found for app %s, unsupported Application configuration", app.Metadata.Name)
 		// technically, unsupported Application configuration is not an error (or is it?)
 		return nil
 	}
 
-	releaseOverrides, err := app.processAppAnnotations(app.Metadata.Annotations, task)
+	releaseOverrides, err := app.generateOverrideFileContent(app.Metadata.Annotations, task)
 	if err != nil {
 		return err
 	}
@@ -252,9 +271,9 @@ func (app *Application) UpdateGitImageTag(task *Task) error {
 	}
 
 	git := updater.GitRepo{
-		RepoURL:    app.Spec.Source.RepoURL,
-		BranchName: app.Spec.Source.TargetRevision,
-		Path:       app.Spec.Source.Path,
+		RepoURL:    gitopsRepo.RepoUrl,
+		BranchName: gitopsRepo.BranchName,
+		Path:       gitopsRepo.Path,
 
 		GitHandler: updater.GitClient{},
 	}
diff --git a/internal/models/gitops.go b/internal/models/gitops.go
new file mode 100644
index 0000000..7ee356c
--- /dev/null
+++ b/internal/models/gitops.go
@@ -0,0 +1,46 @@
+package models
+
+import (
+	"fmt"
+
+	"github.com/go-playground/validator/v10"
+)
+
+type GitopsRepo struct {
+	RepoUrl    string `validate:"required"`
+	BranchName string `validate:"required"`
+	Path       string `validate:"required"`
+}
+
+func NewGitopsRepo(app *Application) (GitopsRepo, error) {
+	if app.Spec.Sources != nil {
+		return extractGitOverrides(app.Metadata.Annotations)
+	}
+	return GitopsRepo{
+		RepoUrl:    app.Spec.Source.RepoURL,
+		BranchName: app.Spec.Source.TargetRevision,
+		Path:       app.Spec.Source.Path,
+	}, nil
+}
+
+func extractGitOverrides(annotations map[string]string) (GitopsRepo, error) {
+	var gr GitopsRepo
+	fields := map[string]*string{
+		managedGitRepo:   &gr.RepoUrl,
+		managedGitBranch: &gr.BranchName,
+		managedGitPath:   &gr.Path,
+	}
+
+	for key, value := range annotations {
+		if field, ok := fields[key]; ok {
+			*field = value
+		}
+	}
+
+	validate := validator.New()
+	if err := validate.Struct(gr); err != nil {
+		return gr, fmt.Errorf("invalid gitops repo: %w", err)
+	}
+
+	return gr, nil
+}
diff --git a/pkg/updater/interfaces.go b/pkg/updater/interfaces.go
index 3283fc2..a62fb67 100644
--- a/pkg/updater/interfaces.go
+++ b/pkg/updater/interfaces.go
@@ -9,7 +9,7 @@ import (
 
 type GitHandler interface {
 	Clone(s storage.Storer, worktree billy.Filesystem, o *git.CloneOptions) (*git.Repository, error)
-	NewPublicKeysFromFile(user, path, passphrase string) (*ssh.PublicKeys, error)
+	AddSSHKey(user, path, passphrase string) (*ssh.PublicKeys, error)
 }
 
 type GitClient struct{}
@@ -18,6 +18,6 @@ func (GitClient) Clone(s storage.Storer, worktree billy.Filesystem, o *git.Clone
 	return git.Clone(s, worktree, o)
 }
 
-func (GitClient) NewPublicKeysFromFile(user, path, passphrase string) (*ssh.PublicKeys, error) {
+func (GitClient) AddSSHKey(user, path, passphrase string) (*ssh.PublicKeys, error) {
 	return ssh.NewPublicKeysFromFile(user, path, passphrase)
 }
diff --git a/pkg/updater/updater.go b/pkg/updater/updater.go
index 0d8751f..96b9070 100644
--- a/pkg/updater/updater.go
+++ b/pkg/updater/updater.go
@@ -52,7 +52,7 @@ func (repo *GitRepo) Clone() error {
 
 	repo.fs = memfs.New()
 
-	if repo.sshAuth, err = repo.GitHandler.NewPublicKeysFromFile("git", sshKeyPath, sshKeyPass); err != nil {
+	if repo.sshAuth, err = repo.GitHandler.AddSSHKey("git", sshKeyPath, sshKeyPass); err != nil {
 		return err
 	}
 


Test patch:
diff --git a/internal/models/gitops_test.go b/internal/models/gitops_test.go
new file mode 100644
index 0000000..277a75a
--- /dev/null
+++ b/internal/models/gitops_test.go
@@ -0,0 +1,156 @@
+package models
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNewGitopsRepo(t *testing.T) {
+	testCases := []struct {
+		name      string
+		app       Application
+		expected  GitopsRepo
+		expectErr bool
+	}{
+		{
+			name: "Sources and annotations are set",
+			app: Application{
+				Metadata: ApplicationMetadata{
+					Annotations: map[string]string{
+						managedGitRepo:   "https://github.com/test/repo.git",
+						managedGitBranch: "main",
+						managedGitPath:   "/path/to/code",
+					},
+				},
+				Spec: ApplicationSpec{
+					Sources: []ApplicationSource{
+						{
+							RepoURL:        "SomeOtherRepo",
+							TargetRevision: "SomeOtherBranch",
+							Path:           "/some/other/path",
+						},
+					},
+				},
+			},
+			expected: GitopsRepo{
+				RepoUrl:    "https://github.com/test/repo.git",
+				BranchName: "main",
+				Path:       "/path/to/code",
+			},
+			expectErr: false,
+		},
+		{
+			name: "Sources are set and annotations are missing",
+			app: Application{
+				Metadata: ApplicationMetadata{
+					Annotations: map[string]string{},
+				},
+				Spec: ApplicationSpec{
+					Sources: []ApplicationSource{
+						{
+							RepoURL:        "SomeOtherRepo",
+							TargetRevision: "SomeOtherBranch",
+							Path:           "/some/other/path",
+						},
+					},
+				},
+			},
+			expected: GitopsRepo{
+				RepoUrl:    "https://github.com/test/repo.git",
+				BranchName: "main",
+				Path:       "/path/to/code",
+			},
+			expectErr: true,
+		},
+		{
+			name: "Single Source and annotations ignored",
+			app: Application{
+				Metadata: ApplicationMetadata{
+					Annotations: map[string]string{
+						managedGitRepo:   "SomeOtherRepo",
+						managedGitBranch: "SomeOtherBranch",
+						managedGitPath:   "/some/other/path",
+					},
+				},
+				Spec: ApplicationSpec{
+					Source: ApplicationSource{
+						RepoURL:        "https://github.com/test/repo.git",
+						TargetRevision: "main",
+						Path:           "/path/to/code",
+					},
+				},
+			},
+			expected: GitopsRepo{
+				RepoUrl:    "https://github.com/test/repo.git",
+				BranchName: "main",
+				Path:       "/path/to/code",
+			},
+			expectErr: false,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			result, err := NewGitopsRepo(&tc.app)
+			if tc.expectErr {
+				assert.Error(t, err)
+			} else {
+				assert.NoError(t, err)
+				assert.Equal(t, tc.expected, result)
+			}
+		})
+
+	}
+}
+
+func TestExtractGitOverrides(t *testing.T) {
+	testCases := []struct {
+		name        string
+		annotations map[string]string
+		expected    GitopsRepo
+		expectErr   bool
+	}{
+		{
+			name: "All fields present",
+			annotations: map[string]string{
+				managedGitRepo:   "https://github.com/test/repo.git",
+				managedGitBranch: "main",
+				managedGitPath:   "/path/to/code",
+			},
+			expected: GitopsRepo{
+				RepoUrl:    "https://github.com/test/repo.git",
+				BranchName: "main",
+				Path:       "/path/to/code",
+			},
+			expectErr: false,
+		},
+		{
+			name: "Missing field",
+			annotations: map[string]string{
+				managedGitRepo:   "https://github.com/test/repo.git",
+				managedGitBranch: "main",
+			},
+			expected:  GitopsRepo{},
+			expectErr: true,
+		},
+		{
+			name:        "No fields",
+			annotations: map[string]string{},
+			expected:    GitopsRepo{},
+			expectErr:   true,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			result, err := extractGitOverrides(tc.annotations)
+			if tc.expectErr {
+				assert.Error(t, err)
+			} else {
+				assert.NoError(t, err)
+				assert.Equal(t, tc.expected, result)
+			}
+		})
+	}
+}
diff --git a/pkg/updater/updater_test.go b/pkg/updater/updater_test.go
index e9d8916..42986a8 100644
--- a/pkg/updater/updater_test.go
+++ b/pkg/updater/updater_test.go
@@ -32,7 +32,7 @@ func TestGitRepoClone(t *testing.T) {
 		{
 			name: "successful clone",
 			mockSSH: func() {
-				mockGitHandler.EXPECT().NewPublicKeysFromFile("git", sshKeyPath, sshKeyPass).Return(&ssh.PublicKeys{}, nil)
+				mockGitHandler.EXPECT().AddSSHKey("git", sshKeyPath, sshKeyPass).Return(&ssh.PublicKeys{}, nil)
 				mockGitHandler.EXPECT().Clone(memory.NewStorage(), memfs.New(), &git.CloneOptions{
 					URL:           "mockRepoURL",
 					ReferenceName: "refs/heads/mockBranch",
@@ -44,9 +44,9 @@ func TestGitRepoClone(t *testing.T) {
 			expected: nil,
 		},
 		{
-			name: "failed NewPublicKeysFromFile",
+			name: "failed AddSSHKey",
 			mockSSH: func() {
-				mockGitHandler.EXPECT().NewPublicKeysFromFile("git", sshKeyPath, sshKeyPass).Return(nil, errors.New("failed to fetch keys"))
+				mockGitHandler.EXPECT().AddSSHKey("git", sshKeyPath, sshKeyPass).Return(nil, errors.New("failed to fetch keys"))
 			},
 			expected: errors.New("failed to fetch keys"),
 		},