feat: impl getObjectFromName (#167)

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- [ ] `npm test` passes
- [ ] tests and/or benchmarks are included
- [ ] documentation is changed or added
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##### Description of change
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Author: killagu

README.md

@@ -632,17 +632,23 @@ export interface Application {
 export interface Application {
   /**
    * 通过一个类来获取实例
-   * 注：app.getEggObject 只能获取 Singleton 实例
    */
   getEggObject<T> (clazz: EggProtoImplClass<T> ): Promise <T>;
+  /**
+   * 通过对象名称来获取实例
+   */
+  getEggObjectFromName<T>(name: string, qualifiers?: QualifierInfo | QualifierInfo[]): Promise<unknown>;
 }
 
 export interface Context {
   /**
    * 通过一个类来获取实例
-   * 注：ctx.getEggObject 可以获取 Singleton/Context 实例
    */
   getEggObject<T> (clazz: EggProtoImplClass<T> ): Promise <T>;
+  /**
+   * 通过对象名称来获取实例
+   */
+  getEggObjectFromName<T>(name: string, qualifiers?: QualifierInfo | QualifierInfo[]): Promise<unknown>;
 }
 ```
 

core/runtime/src/factory/EggContainerFactory.ts

@@ -67,6 +67,19 @@ export class EggContainerFactory {
     return await this.getOrCreateEggObject(proto, name);
   }
 
+  /**
+   * get or create egg object from the Name
+   * If get singleton egg object in context,
+   * will create context egg object for it.
+   */
+  static async getOrCreateEggObjectFromName(name: EggObjectName, qualifiers?: QualifierInfo[]): Promise<EggObject> {
+    const proto = EggPrototypeFactory.instance.getPrototype(name, undefined, qualifiers);
+    if (!proto) {
+      throw new Error(`can not get proto for clazz ${String(name)}`);
+    }
+    return await this.getOrCreateEggObject(proto, name);
+  }
+
   static getEggObject(proto: EggPrototype, name?: EggObjectName): EggObject {
     const container = this.getContainer(proto);
     name = name || proto.name;

core/runtime/test/EggObject.test.ts

@@ -74,6 +74,11 @@ describe('test/EggObject.test.ts', () => {
         assert.equal(barObj2, barObj);
         assert.equal(barObj2.obj, barObj.obj);
 
+        // get obj from name
+        const barObj3 = await EggContainerFactory.getOrCreateEggObjectFromName('bar');
+        assert.equal(barObj3, barObj);
+        assert.equal(barObj3.obj, barObj.obj);
+
         await TestUtil.destroyLoadUnitInstance(instance);
         const called = bar.getLifecycleCalled();
         assert.deepStrictEqual(called, [

plugin/tegg/app/extend/application.ts

@@ -95,4 +95,12 @@ export default {
     const eggObject = await EggContainerFactory.getOrCreateEggObjectFromClazz(clazz, name, qualifiers);
     return eggObject.obj;
   },
+
+  async getEggObjectFromName(name: string, qualifiers?: QualifierInfo | QualifierInfo[]) {
+    if (qualifiers) {
+      qualifiers = Array.isArray(qualifiers) ? qualifiers : [ qualifiers ];
+    }
+    const eggObject = await EggContainerFactory.getOrCreateEggObjectFromName(name, qualifiers);
+    return eggObject.obj;
+  },
 };

plugin/tegg/app/extend/context.ts

@@ -2,7 +2,7 @@ import { Context } from 'egg';
 import { EggContext } from '@eggjs/tegg-runtime';
 import { TEGG_CONTEXT } from '@eggjs/egg-module-common';
 import ctxLifecycleMiddleware from '../../lib/ctx_lifecycle_middleware';
-import { EggProtoImplClass, PrototypeUtil } from '@eggjs/tegg';
+import { EggProtoImplClass, PrototypeUtil, QualifierInfo } from '@eggjs/tegg';
 import { EggPrototype } from '@eggjs/tegg-metadata';
 
 export interface TEggPluginContext extends Context {
@@ -30,4 +30,12 @@ export default {
     const eggObject = await this.app.eggContainerFactory.getOrCreateEggObject(proto, name ?? proto.name);
     return eggObject.obj;
   },
+
+  async getEggObjectFromName(this: Context, name: string, qualifiers?: QualifierInfo | QualifierInfo[]) {
+    if (qualifiers) {
+      qualifiers = Array.isArray(qualifiers) ? qualifiers : [ qualifiers ];
+    }
+    const eggObject = await this.app.eggContainerFactory.getOrCreateEggObjectFromName(name, qualifiers);
+    return eggObject.obj;
+  },
 };

plugin/tegg/test/app/extend/context.test.ts

@@ -42,6 +42,18 @@ describe('test/app/extend/context.test.ts', () => {
     });
   });
 
+  describe('getEggObjectFromName', () => {
+    it('should work', async () => {
+      await app.mockModuleContextScope(async ctx => {
+        const appService = await ctx.getEggObjectFromName('appService');
+        assert(appService instanceof AppService);
+
+        const persistenceService = await ctx.getEggObjectFromName('persistenceService');
+        assert(persistenceService instanceof PersistenceService);
+      });
+    });
+  });
+
   describe('beginModuleScope', () => {
     it('should be reentrant', async () => {
       await app.mockModuleContextScope(async ctx => {

plugin/tegg/typings/index.d.ts

@@ -19,7 +19,7 @@ import {
   EggContext,
 } from '@eggjs/tegg-runtime';
 import { LoaderFactory } from '@eggjs/tegg-loader';
-import { IdenticalUtil, EggProtoImplClass } from '@eggjs/tegg';
+import { IdenticalUtil, EggProtoImplClass, QualifierInfo } from '@eggjs/tegg';
 import { ModuleHandler } from '../lib/ModuleHandler';
 import { EggContextHandler } from '../lib/EggContextHandler';
 
@@ -60,6 +60,7 @@ declare module 'egg' {
     module: EggModule & EggApplicationModule;
 
     getEggObject<T>(clazz: EggProtoImplClass<T>): Promise<T>;
+    getEggObjectFromName<T>(name: string, qualifiers?: QualifierInfo | QualifierInfo[]): Promise<unknown>;
   }
 
   export interface TEggContext {