Get API server from cache first. (#309)

* fix doc link

* Add more warning for AV.initialize() .

* Add sync function for getting local storage.

* Get API server from cache first.

* Readme add install part.

* Add async get API Host from cache

* fix install name

* getServerUrl -> refreshServerUrl

* Add set and setAsync to Cache module

* Add Cache module unit test

* Must run getServerURL() before all request.

* Promise -> AVPromise

* Remove cache async function

* fix typo

Author: wangxiao

README.md

@@ -4,12 +4,15 @@ JavaScript SDK for [LeanCloud](http://leancloud.cn/).
 
 ## 使用方法请看 [官方文档](https://leancloud.cn/docs/leanstorage_guide-js.html)
 
-## 版本说明
+## 安装
 
-* 0.x.y 版本，是不兼容 React Native 运行时的老版本 SDK，相对稳定，云引擎主要依赖这个分支版本。
-* 1.0.0-x 版本，是我们最新开发的兼容 React Native 运行时的版本，处于开放测试阶段，欢迎大家尝试。我们最终将使用这个分支替代云引擎里的 `0.x.y` 版本。
+```
+// npm 安装
+npm install leancloud-storage --save
 
-可以使用以下命令安装 1.0.0-x 版本：`npm install avoscloud-sdk@next`。
+// bower 安装
+bower install leancloud-storage --save
+```
 
 ## 贡献代码
 

src/cache.js

@@ -6,27 +6,31 @@
 const storage = require('./localstorage');
 const AV = require('./av');
 
-const remove = exports.remove = storage.removeItemAsync.bind(storage);
+const removeAsync = exports.removeAsync = storage.removeItemAsync.bind(storage);
 
-exports.get = (key) =>
-  storage.getItemAsync(`${AV.applicationId}/${key}`)
-    .then(cache => {
-      try {
-        cache = JSON.parse(cache);
-      } catch (e) {
-        return null;
-      }
-      if (cache) {
-        const expired = cache.expiredAt && cache.expiredAt < Date.now();
-        if (!expired) {
-          return cache.value;
-        }
-        return remove(key).then(() => null);
-      }
-      return null;
-    });
+const getCacheData = (cacheData, key) => {
+  try {
+    cacheData = JSON.parse(cacheData);
+  } catch (e) {
+    return null;
+  }
+  if (cacheData) {
+    const expired = cacheData.expiredAt && cacheData.expiredAt < Date.now();
+    if (!expired) {
+      return cacheData.value;
+    }
+    return removeAsync(key).then(() => null);
+  }
+  return null;
+};
+
+exports.getAsync = (key) => {
+  key = `${AV.applicationId}/${key}`;
+  return storage.getItemAsync(key)
+    .then(cache => getCacheData(cache, key));
+};
 
-exports.set = (key, value, ttl) => {
+exports.setAsync = (key, value, ttl) => {
   const cache = { value };
   if (typeof ttl === 'number') {
     cache.expiredAt = Date.now() + ttl;

src/request.js

@@ -6,10 +6,19 @@
 const request = require('superagent');
 const debug = require('debug')('request');
 const md5 = require('md5');
-const Promise = require('./promise');
+const AVPromise = require('./promise');
 const Cache = require('./cache');
 const AVError = require('./error');
 const AV = require('./av');
+const _ = require('underscore');
+
+const getServerURLPromise = new AVPromise();
+
+// 服务器请求的节点 host
+const API_HOST = {
+  cn: 'https://api.leancloud.cn',
+  us: 'https://us-api.leancloud.cn',
+};
 
 // 计算 X-LC-Sign 的签名方法
 const sign = (key, isMasterKey) => {
@@ -65,7 +74,7 @@ const checkRouter = (router) => {
 const ajax = (method, resourceUrl, data, headers = {}, onprogress) => {
   debug(method, resourceUrl, data, headers);
 
-  const promise = new Promise();
+  const promise = new AVPromise();
   const req = request(method, resourceUrl)
     .set(headers)
     .send(data)
@@ -109,7 +118,7 @@ const setHeaders = (sessionToken) => {
     headers['User-Agent'] = AV._config.userAgent || `AV/${AV.version}; Node.js/${process.version}`;
   }
 
-  const promise = new Promise();
+  const promise = new AVPromise();
 
   // Pass the session token
   if (sessionToken) {
@@ -179,20 +188,23 @@ const cacheServerURL = (serverURL, ttl) => {
   if (typeof ttl !== 'number') {
     ttl = 3600;
   }
-  Cache.set('APIServerURL', serverURL, ttl * 1000);
+  return Cache.setAsync('APIServerURL', serverURL, ttl * 1000);
 };
 
 // handle AV._request Error
 const handleError = (res) => {
-  const promise = new Promise();
+  const promise = new AVPromise();
   /**
     When API request need to redirect to the right location,
     can't use browser redirect by http status 307, as the reason of CORS,
     so API server response http status 410 and the param "location" for this case.
   */
   if (res.statusCode === 410) {
-    cacheServerURL(res.response.api_server, res.response.ttl);
-    promise.resolve(res.response.location);
+    cacheServerURL(res.response.api_server, res.response.ttl).then(() => {
+      promise.resolve(res.response.location);
+    }).catch((error) => {
+      promise.reject(error);
+    });
   } else {
     let errorJSON = { code: -1, error: res.responseText };
     if (res.response && res.response.code) {
@@ -213,40 +225,44 @@ const handleError = (res) => {
   return promise;
 };
 
-const setServerUrlByRegion = (region = 'cn') => {
-  // 服务器请求的节点 host
-  const API_HOST = {
-    cn: 'https://api.leancloud.cn',
-    us: 'https://us-api.leancloud.cn',
-  };
+const setServerUrl = (serverURL) => {
+  AV._config.APIServerURL = `https://${serverURL}`;
 
-  const AVConfig = AV._config;
-  AVConfig.region = region;
+  // 根据新 URL 重新设置区域
+  const newRegion = _.findKey(API_HOST, item => item === AV._config.APIServerURL);
+  if (newRegion) {
+    AV._config.region = newRegion;
+  }
+};
+
+const refreshServerUrl = () => {
+  const url = `https://app-router.leancloud.cn/1/route?appId=${AV.applicationId}`;
+  return ajax('get', url).then(servers => {
+    if (servers.api_server) {
+      setServerUrl(servers.api_server);
+      return cacheServerURL(servers.api_server, servers.ttl);
+    }
+  });
+};
+
+const setServerUrlByRegion = (region = 'cn') => {
   // 如果用户在 init 之前设置了 APIServerURL，则跳过请求 router
-  if (AVConfig.APIServerURL) {
+  if (AV._config.APIServerURL) {
     return;
   }
-  AVConfig.APIServerURL = API_HOST[region];
-  if (region === 'cn') {
-    Cache.get('APIServerURL').then(cachedServerURL => {
-      if (cachedServerURL) {
-        return cachedServerURL;
-      } else {
-        return ajax('get', `https://app-router.leancloud.cn/1/route?appId=${AV.applicationId}`)
-          .then(servers => {
-            if (servers.api_server) {
-              cacheServerURL(servers.api_server, servers.ttl);
-              return servers.api_server;
-            }
-          });
-      }
-    }).then(serverURL => {
-      // 如果用户在 init 之后设置了 APIServerURL，保持用户设置
-      if (AVConfig.APIServerURL === API_HOST[region]) {
-        AVConfig.APIServerURL = `https://${serverURL}`;
-      }
-    });
-  }
+  AV._config.region = region;
+  AV._config.APIServerURL = API_HOST[region];
+
+  Cache.getAsync('APIServerURL').then((serverURL) => {
+    if (serverURL) {
+      setServerUrl(serverURL);
+      getServerURLPromise.resolve();
+    } else {
+      refreshServerUrl().then(() => {
+        getServerURLPromise.resolve();
+      });
+    }
+  });
 };
 
 /**
@@ -266,16 +282,18 @@ const AVRequest = (route, className, objectId, method, dataObject = {}, sessionT
   }
 
   checkRouter(route);
-  const apiURL = createApiUrl(route, className, objectId, method, dataObject);
 
-  return setHeaders(sessionToken).then(
-    headers => ajax(method, apiURL, dataObject, headers)
-      .then(
-        null,
-        res => handleError(res)
-          .then(location => ajax(method, location, dataObject, headers))
-      )
-  );
+  return getServerURLPromise.always(() => {
+    const apiURL = createApiUrl(route, className, objectId, method, dataObject);
+    return setHeaders(sessionToken).then(
+      headers => ajax(method, apiURL, dataObject, headers)
+        .then(
+          null,
+          res => handleError(res)
+            .then(location => ajax(method, location, dataObject, headers))
+        )
+    );
+  });
 };
 
 module.exports = {

src/utils.js

@@ -159,7 +159,9 @@ const init = (AV) => {
       // 兼容旧版本的初始化方法
       case 2:
       case 3:
-        console.warn('Please use AV.init() to replace AV.initialize() .');
+        console.warn('Please use AV.init() to replace AV.initialize(), ' +
+         'AV.init() need an Object param, like { appId: \'YOUR_APP_ID\', appKey: \'YOUR_APP_KEY\' } . ' +
+         'Docs: https://leancloud.cn/docs/sdk_setup-js.html');
         if (!AVConfig.isNode && args.length === 3) {
           masterKeyWarn();
         }

test/cache.js

@@ -5,14 +5,14 @@ var wait = function wait(time) {
   });
 };
 
-describe('Cache', function () {
+describe('Cache async', function () {
   var getValue = function getValue() {
-    return Cache.get('__test');
+    return Cache.getAsync('__test');
   };
-  it('get/set', function () {
-    return Cache.set('__test', 1).then(getValue).then(function (value) {
+  it('get/set async', function () {
+    return Cache.setAsync('__test', 1).then(getValue).then(function (value) {
       expect(value).to.be(1);
-      return Cache.set('__test', '1', 100).then(getValue);
+      return Cache.setAsync('__test', '1', 100).then(getValue);
     }).then(function (value) {
       expect(value).to.be('1');
       return wait(110).then(getValue);