微信小程序wx.request拦截器使用详解

// 官方代码示例
wx.request({
 url: 'test.php', //仅为示例，并非真实的接口地址
 data: {
  x: '',
  y: ''
 },
 header: {
  'content-type': 'application/json' // 默认值
 },
 success (res) {
  console.log(res.data)
 }
 fail(res){
 console.log(res)
 }
})

const app = getApp();
const appid = 'xxxx';
const appSecret = 'xxxxxx';
let ajaxNum = 0;

// 获取accessToken
function getAccessToken(callback) {
 wx.request({
  url: '/api/Token',
  data: {
   appid: aesEncrypt(appid),// aesEncrypt():自定义的用crypto-js.js进行aes加密的方法,这里只需要知道加密了即可，不需要关注此方法
   appSecret: aesEncrypt(appSecret),
  },
  success: function (res) {
   if(res.statusCode ===200 && res.data.code === 0) {
    let accesstoken = res.data.data.accesstoken;
    if (typeof (callback) === 'function' && accesstoken) {
     callback(accesstoken);
    }
   }
  },
 })
}

// 封装request请求
const myRequest = options => {
 if(options) {
  getAccessToken(function (accesstoken){
   // header 设置Content-Type，accesstoken, usertoken, noncestr, timestamp等信息，与后台协商好
   if(options.header === undefined || options.header === null) {
    options.header = {};
   }
   options.header['Content-Type'] = 'application/x-www-form-urlencoded; charset=UTF-8';
   // usertoken在登录后保存在缓存中，所以从缓存中取出，放在header
   let usertoken = wx.getStorageSync('usertoken');
   if (usertoken) {
    options.header['usertoken'] = usertoken;
   }
   // 自定义getNoncestr()设置随机字符串，getTimestamp()获取时间戳
   let noncestr = getNoncestr();
   let timestamp = getTimestamp();
   // sign进行加密
   let sign = getSign(accesstoken, appid, appSecret, noncestr, timestamp);
   if (timestamp) {
    options.header['timestamp'] = timestamp;
   }
   if (noncestr) {
    options.header['noncestr'] = noncestr;
   }
   if (sign) {
    options.header['sign'] = sign;
   }
   //url
   let baseUrl = config.BASE_HOST;
   if (options.url.indexOf('http') != 0) {
    options.url = baseUrl + options.url;
   }
   // method、data
  if (options.method === undefined || options.method === null) {
   options.method = 'post';
  }
  if (options.method.toLowerCase() === 'post') {
   if(options.data) {
    let dataStr = JSON.stringify(options.data);
    let base64Str = base64Encrypt(dataStr);
    options.data = serializeData({ param: base64Str });
   }
  }
  //success
  if (options.success && typeof(options.success) === 'function') {
   let successCallback = options.success;
   options.success = function(res) {
    // 判断不同的返回码 200/404
    if (res.statusCode === 200) {
     try {
     // 接收的后台数据用自定义base64解密方法解密后转为对象 
      let str = base64Decrypt(res.data);
      let data = JSON.parse(str);
      if (parseInt(data.resultCode, 10) === -1) {//后台商议好的状态码，-2未登录，-1-3后台出错
       console.error('网络超时，请稍后重试');
      } else if (parseInt(data.resultCode, 10) === -3) {
       console.error(data.msg);
      } else if (parseInt(data.resultCode, 10) === -2){
       console.log("用户未登录-ajax");
      }
      res.data = data;
      //调用自定义的success
      successCallback(res);
     } catch (e) {
      console.error('出错了，' + e + ',接口返回数据:' + res.data);
     }
    } else if(res.statusCode === 404) {
      console.log('404');
    }
   }
  }
   //执行微信的请求
   wx.request(options);
  });
 } 
}


module.exports = {
 myRequest: myRequest

const ajax = require('ajax.js');
 ajax.javaRequest({
   url: '/xxx',
   data: {
    xxxx: xxx
   },
   method: 'POST',
   success: res => {
      console.log(res, '成功')
   }
  })