define BackendFeatureFactory

Signed-off-by: Vincenzo Scamporlino <vincenzos@spotify.com>

packages/backend-plugin-api/src/wiring/factories.ts

@@ -17,11 +17,10 @@
 import {
   BackendModuleRegistrationPoints,
   BackendPluginRegistrationPoints,
-  BackendFeature,
   ExtensionPoint,
-  InternalBackendFeature,
   InternalBackendModuleRegistration,
   InternalBackendPluginRegistration,
+  BackendFeatureFactory,
 } from './types';
 
 /**
@@ -92,9 +91,10 @@ export const catalogPlugin = createBackendPlugin({
  */
 export function createBackendPlugin<TOptions extends [options?: object] = []>(
   config: BackendPluginConfig | ((...params: TOptions) => BackendPluginConfig),
-): (...params: TOptions) => BackendFeature {
+): BackendFeatureFactory<TOptions> {
   const configCallback = typeof config === 'function' ? config : () => config;
-  const factory = (...options: TOptions): InternalBackendFeature => {
+
+  const factory: BackendFeatureFactory<TOptions> = (...options) => {
     const c = configCallback(...options);
 
     let registrations: InternalBackendPluginRegistration[];
@@ -149,8 +149,8 @@ export function createBackendPlugin<TOptions extends [options?: object] = []>(
       },
     };
   };
-
   factory.$$type = '@backstage/BackendFeatureFactory';
+
   return factory;
 }
 
@@ -184,9 +184,9 @@ export interface BackendModuleConfig {
  */
 export function createBackendModule<TOptions extends [options?: object] = []>(
   config: BackendModuleConfig | ((...params: TOptions) => BackendModuleConfig),
-): (...params: TOptions) => BackendFeature {
+): BackendFeatureFactory<TOptions> {
   const configCallback = typeof config === 'function' ? config : () => config;
-  return (...options: TOptions): InternalBackendFeature => {
+  const factory: BackendFeatureFactory<TOptions> = (...options: TOptions) => {
     const c = configCallback(...options);
 
     let registrations: InternalBackendModuleRegistration[];
@@ -231,4 +231,7 @@ export function createBackendModule<TOptions extends [options?: object] = []>(
       },
     };
   };
+  factory.$$type = '@backstage/BackendFeatureFactory';
+
+  return factory;
 }

packages/backend-plugin-api/src/wiring/index.ts

@@ -28,5 +28,6 @@ export type {
   BackendModuleRegistrationPoints,
   BackendPluginRegistrationPoints,
   BackendFeature,
+  BackendFeatureFactory,
   ExtensionPoint,
 } from './types';

packages/backend-plugin-api/src/wiring/types.ts

@@ -67,6 +67,14 @@ export interface BackendModuleRegistrationPoints {
   }): void;
 }
 
+/** @public */
+export interface BackendFeatureFactory<
+  TOptions extends [options?: object] = [],
+> {
+  (...options: TOptions): BackendFeature;
+  $$type: '@backstage/BackendFeatureFactory';
+}
+
 /** @public */
 export interface BackendFeature {
   // NOTE: This type is opaque in order to simplify future API evolution.