refactor: app.cluster auto bind this

docs/source/zh-cn/basics/router.md

@@ -56,7 +56,7 @@ app.verb('router-name', 'path-match', middleware1, ..., middlewareN, 'controller
 - router-name 给路由设定一个别名，可以通过 Helper 提供的辅助函数 `pathFor` 和 `urlFor` 来生成 URL。(可选)
 - path-match - 路由 URL 路径。
 - middleware1 - 在 Router 里面可以配置多个 Middleware。(可选)
-- controller.action - 注意是字符串，框架会自动从 `app/controller` 目录中区查找同名 Controller，
+- controller.action - 注意是字符串，框架会自动从 `app/controller` 目录中去查找同名 Controller，
 并且把处理指定到配置的 action 方法。如果 Controller 文件直接 export 一个方法，可以省略 action。
 
 ### 注意事项

lib/egg.js

@@ -57,6 +57,36 @@ class EggApplication extends EggCore {
 
     this[CLUSTER_CLIENTS] = [];
 
+    /**
+     * Wrap the Client with Leader/Follower Pattern
+     *
+     * @description almost the same as Agent.cluster API, the only different is that this method create Follower.
+     *
+     * @see https://github.com/node-modules/cluster-client
+     * @param {Function} clientClass - client class function
+     * @param {Object} [options]
+     *   - {Boolean} [autoGenerate] - whether generate delegate rule automatically, default is true
+     *   - {Function} [formatKey] - a method to tranform the subscription info into a string，default is JSON.stringify
+     *   - {Object} [transcode|JSON.stringify/parse]
+     *     - {Function} encode - custom serialize method
+     *     - {Function} decode - custom deserialize method
+     *   - {Boolean} [isBroadcast] - whether broadcast subscrption result to all followers or just one, default is true
+     *   - {Number} [responseTimeout] - response timeout, default is 3 seconds
+     *   - {Number} [maxWaitTime|30000] - leader startup max time, default is 30 seconds
+     * @return {ClientWrapper} wrapper
+     */
+    this.cluster = (clientClass, options) => {
+      options = options || {};
+      // cluster need a port that can't conflict on the environment
+      options.port = this._options.clusterPort;
+      // agent worker is leader, app workers are follower
+      options.isLeader = this.type === 'agent';
+      options.logger = this.coreLogger;
+      const client = cluster(clientClass, options);
+      this._patchClusterClient(client);
+      return client;
+    };
+
     // register close function
     this.beforeClose(() => {
       for (const logger of this.loggers.values()) {
@@ -317,37 +347,6 @@ class EggApplication extends EggCore {
     singleton.init();
   }
 
-
-  /**
-   * Wrap the Client with Leader/Follower Pattern
-   *
-   * @description almost the same as Agent.cluster API, the only different is that this method create Follower.
-   *
-   * @see https://github.com/node-modules/cluster-client
-   * @param {Function} clientClass - client class function
-   * @param {Object} [options]
-   *   - {Boolean} [autoGenerate] - whether generate delegate rule automatically, default is true
-   *   - {Function} [formatKey] - a method to tranform the subscription info into a string，default is JSON.stringify
-   *   - {Object} [transcode|JSON.stringify/parse]
-   *     - {Function} encode - custom serialize method
-   *     - {Function} decode - custom deserialize method
-   *   - {Boolean} [isBroadcast] - whether broadcast subscrption result to all followers or just one, default is true
-   *   - {Number} [responseTimeout] - response timeout, default is 3 seconds
-   *   - {Number} [maxWaitTime|30000] - leader startup max time, default is 30 seconds
-   * @return {ClientWrapper} wrapper
-   */
-  cluster(clientClass, options) {
-    options = options || {};
-    // cluster need a port that can't conflict on the environment
-    options.port = this._options.clusterPort;
-    // agent worker is leader, app workers are follower
-    options.isLeader = this.type === 'agent';
-    options.logger = this.coreLogger;
-    const client = cluster(clientClass, options);
-    this._patchClusterClient(client);
-    return client;
-  }
-
   _patchClusterClient(client) {
     const create = client.create;
     client.create = (...args) => {

test/fixtures/apps/cluster_mod_app/app.js

@@ -6,7 +6,8 @@ module.exports = function(app) {
   const done = app.readyCallback('register_client', {
     isWeakDep: app.config.runMode === 0,
   });
-  app.registryClient = app.cluster(RegistryClient).create();
+  const cluster = app.cluster;
+  app.registryClient = cluster(RegistryClient).create();
   app.registryClient.ready(done);
 
   app.registryClient.subscribe({