fix(hydrator): don't use manifest-generate-paths (argoproj#22039) (ar…

…goproj#22015)

Signed-off-by: Michael Crenshaw <350466+crenshaw-dev@users.noreply.github.com>
Signed-off-by: Harshit-Bajpai <Harshit.Bajpai@skyscanner.net>

controller/hydrator_dependencies.go

@@ -30,17 +30,26 @@ func (ctrl *ApplicationController) GetProcessableApps() (*appv1.ApplicationList,
 	return ctrl.getAppList(metav1.ListOptions{})
 }
 
-func (ctrl *ApplicationController) GetRepoObjs(app *appv1.Application, source appv1.ApplicationSource, revision string, project *appv1.AppProject) ([]*unstructured.Unstructured, *apiclient.ManifestResponse, error) {
-	sources := []appv1.ApplicationSource{source}
-	revisions := []string{revision}
+func (ctrl *ApplicationController) GetRepoObjs(origApp *appv1.Application, drySource appv1.ApplicationSource, revision string, project *appv1.AppProject) ([]*unstructured.Unstructured, *apiclient.ManifestResponse, error) {
+	drySources := []appv1.ApplicationSource{drySource}
+	dryRevisions := []string{revision}
 
 	appLabelKey, err := ctrl.settingsMgr.GetAppInstanceLabelKey()
 	if err != nil {
 		return nil, nil, fmt.Errorf("failed to get app instance label key: %w", err)
 	}
 
+	app := origApp.DeepCopy()
+	// Remove the manifest generate path annotation, because the feature will misbehave for apps using source hydrator.
+	// Setting this annotation causes GetRepoObjs to compare the dry source commit to the most recent synced commit. The
+	// problem is that the most recent synced commit is likely on the hydrated branch, not the dry branch. The
+	// comparison will throw an error and break hydration.
+	//
+	// The long-term solution will probably be to persist the synced _dry_ revision and use that for the comparison.
+	delete(app.Annotations, appv1.AnnotationKeyManifestGeneratePaths)
+
 	// FIXME: use cache and revision cache
-	objs, resp, _, err := ctrl.appStateManager.GetRepoObjs(app, sources, appLabelKey, revisions, true, true, false, project, false, false)
+	objs, resp, _, err := ctrl.appStateManager.GetRepoObjs(app, drySources, appLabelKey, dryRevisions, true, true, false, project, false, false)
 	if err != nil {
 		return nil, nil, fmt.Errorf("failed to get repo objects: %w", err)
 	}

docs/user-guide/source-hydrator.md

@@ -166,6 +166,17 @@ hydrator will not be able to use a project-scoped push secret and will require a
 Credential templates allow a single credential to be used for multiple repositories. The source hydrator does not 
 currently support credential templates. You will need a separate credential for each repository.
 
+### `manifest-generate-paths` Annotation Support
+
+The source hydrator does not currently support the [manifest-generate-paths annotation](../operator-manual/high_availability.md#manifest-paths-annotation) 
+for work avoidance on hydration of dry commits. In other words, the source hydrator is not able to skip hydration of dry 
+commits that have not changed relevant files.
+
+The application controller _does_ honor the `manifest-generate-paths` annotation when syncing the hydrated manifests.
+So if your application hydrates to the `foo` directory, and the `manifest-generate-paths` annotation is set to `foo`, 
+then the application controller will not re-hydrate the manifests after a commit that only affects files in the `bar`
+directory.
+
 ## Prerequisites
 
 ### Handle Secrets on the Destination Cluster