feat: add ip setter on request (#138)

closes https://github.com/eggjs/egg/issues/123

app/extend/context.js

@@ -398,4 +398,5 @@ delegate(proto, 'request')
   .getter('isAjax')
   .getter('acceptJSON')
   .getter('queries')
-  .getter('accept');
+  .getter('accept')
+  .access('ip');

app/extend/request.js

@@ -71,12 +71,13 @@ module.exports = {
   },
 
   /**
-   * 返回远程 ip 地址，总是返回 ipv4
+   * Request remote IPv4 address
    * @member {String} Request#ip
    * @example
    * ```js
    * this.request.ip
    * => '127.0.0.1'
+   * => '111.10.2.1'
    * ```
    */
   get ip() {
@@ -84,13 +85,20 @@ module.exports = {
       return this._ip;
     }
     const ip = this.ips[0] || this.socket.remoteAddress;
-    // ::ffff:x.x.x.x/96 是用于IPv4映射地址
-    // 如果是 IPV6 也不会做处理，现在还未遇到 IPV6 的场景
+    // will be '::ffff:x.x.x.x', should conver to standard IPv4 format
     // https://zh.wikipedia.org/wiki/IPv6
     this._ip = ip && ip.indexOf('::ffff:') > -1 ? ip.substring(7) : ip;
     return this._ip;
   },
 
+  /**
+   * Set the remote address
+   * @param {String} ip - IPv4 address
+   */
+  set ip(ip) {
+    this._ip = ip;
+  },
+
   /**
    * 从请求头获取所有 ip
    * 1. 先从 `X-Forwarded-For` 获取，这个值是从 spanner 传递过来的，如果前置没有 spanner 返回为空

test/app/extend/context.test.js

@@ -5,8 +5,6 @@ const path = require('path');
 const mm = require('egg-mock');
 const request = require('supertest');
 const sleep = require('ko-sleep');
-
-
 const utils = require('../../utils');
 
 describe('test/app/extend/context.test.js', () => {
@@ -389,4 +387,32 @@ describe('test/app/extend/context.test.js', () => {
         .should.match(/\[egg:background] task:mockError fail \(\d+ms\)/);
     });
   });
+
+  describe('ctx.ip', () => {
+    let app;
+    before(() => {
+      app = utils.app('apps/demo');
+      return app.ready();
+    });
+    after(() => app.close());
+    afterEach(mm.restore);
+
+    it('should get current request ip', () => {
+      return request(app.callback())
+        .get('/ip')
+        .expect(200)
+        .expect({
+          ip: '127.0.0.1',
+        });
+    });
+
+    it('should set current request ip', () => {
+      return request(app.callback())
+        .get('/ip?set_ip=10.2.2.2')
+        .expect(200)
+        .expect({
+          ip: '10.2.2.2',
+        });
+    });
+  });
 });

test/fixtures/apps/demo/app/controller/ip.js

@@ -0,0 +1,10 @@
+'use strict';
+
+module.exports = function* () {
+  if (this.query.set_ip) {
+    this.ip = this.query.set_ip;
+  }
+  this.body = {
+    ip: this.ip,
+  };
+};

test/fixtures/apps/demo/app/router.js

@@ -9,4 +9,5 @@ module.exports = app => {
   app.get('/user.json', function*() {
     this.jsonp = { name: 'fengmk2' };
   });
+  app.get('/ip', app.controller.ip);
 };