Remove the need for plugins to implement AdmissionHandler for v0alpha1 (#93272)

pkg/registry/apis/datasource/register.go

@@ -66,8 +66,6 @@ func RegisterAPIService(
 	var err error
 	var builder *DataSourceAPIBuilder
 	all := pluginStore.Plugins(context.Background(), plugins.TypeDataSource)
-	// ATTENTION: Adding a datasource here requires the plugin to implement
-	// an AdmissionHandler to validate the datasource settings.
 	ids := []string{
 		"grafana-testdata-datasource",
 		"prometheus",

pkg/services/datasources/service/datasource.go

@@ -367,6 +367,10 @@ func (s *Service) prepareInstanceSettings(ctx context.Context, settings *backend
 		rsp, err := s.pluginClient.ValidateAdmission(ctx, req)
 		if err != nil {
 			if errors.Is(err, plugins.ErrMethodNotImplemented) {
+				if settings.APIVersion == "v0alpha1" {
+					// For v0alpha1 we don't require plugins to implement ValidateAdmission
+					return settings, nil
+				}
 				return nil, errutil.Internal("plugin.unimplemented").
 					Errorf("plugin (%s) with apiVersion=%s must implement ValidateAdmission", p.ID, settings.APIVersion)
 			}
@@ -388,6 +392,10 @@ func (s *Service) prepareInstanceSettings(ctx context.Context, settings *backend
 	rsp, err := s.pluginClient.MutateAdmission(ctx, req)
 	if err != nil {
 		if errors.Is(err, plugins.ErrMethodNotImplemented) {
+			if settings.APIVersion == "v0alpha1" {
+				// For v0alpha1 we don't require plugins to implement MutateAdmission
+				return settings, nil
+			}
 			return nil, errutil.Internal("plugin.unimplemented").
 				Errorf("plugin (%s) with apiVersion=%s must implement MutateAdmission", p.ID, settings.APIVersion)
 		}

pkg/services/datasources/service/datasource_test.go

@@ -135,13 +135,35 @@ func TestService_AddDataSource(t *testing.T) {
 				OrgID:      1,
 				Type:       "test", // required to validate apiserver
 				Name:       "test",
-				APIVersion: "v0alpha1",
+				APIVersion: "v1",
 			}
 			_, err := dsService.AddDataSource(context.Background(), cmd)
 			require.NoError(t, err)
 			require.True(t, validateExecuted)
 		})
 
+		t.Run("should ignore if AdmissionHandler is not implemented for v0alpha1", func(t *testing.T) {
+			dsService := initDSService(t)
+			dsService.pluginStore = &pluginstore.FakePluginStore{
+				PluginList: []pluginstore.Plugin{{
+					JSONData: plugins.JSONData{
+						ID:   "test",
+						Type: plugins.TypeDataSource,
+						Name: "test",
+					},
+				}},
+			}
+			dsService.pluginClient = &pluginfakes.FakePluginClient{}
+			cmd := &datasources.AddDataSourceCommand{
+				OrgID:      1,
+				Type:       "test", // required to validate apiserver
+				Name:       "test",
+				APIVersion: "v0alpha1",
+			}
+			_, err := dsService.AddDataSource(context.Background(), cmd)
+			require.NoError(t, err)
+		})
+
 		t.Run("should fail at validation", func(t *testing.T) {
 			dsService := initDSService(t)
 			dsService.pluginStore = &pluginstore.FakePluginStore{