微信小程序-获取用户session_key,openid,unionid - 后端为 nodejs
微信小程序-获取用户session_key,openid,unionid - 后端为nodejs8.0+
步骤：
1、通过wx.login接口获取code既jscode，传递到后端；
2、后端请求
https://api.weixin.qq.com/sns/jscode2session?appid=APPID&secret=SECRET&js_code=JSCODE&grant_type=authorization_code
地址，就能获取到openid和unionid。
小程序接口promise化和封装
1、utils文件夹下创建wechat.js文件
-
/**
-
* Promise化小程序接口
-
*/
-
class Wechat {
-
/**
-
* 登陆
-
* @return {Promise}
-
*/
-
static login() {
-
return
new
Promise(
(resolve, reject) => wx.login({
success: resolve,
fail: reject }));
-
};
-
-
/**
-
* 获取用户信息
-
* @return {Promise}
-
*/
-
static getUserInfo() {
-
return
new
Promise(
(resolve, reject) => wx.getUserInfo({
success: resolve,
fail: reject }));
-
};
-
-
/**
-
* 发起网络请求
-
* @param {string} url
-
* @param {object} params
-
* @return {Promise}
-
*/
-
static request(url, params, method =
"GET", type =
"json") {
-
console.log(
"向后端传递的参数", params);
-
return
new
Promise(
(resolve, reject) => {
-
let opts = {
-
url: url,
-
data:
Object.assign({}, params),
-
method: method,
-
header: {
'Content-Type': type },
-
success: resolve,
-
fail: reject
-
}
-
console.log(
"请求的URL", opts.url);
-
wx.request(opts);
-
});
-
};
-
-
/**
-
* 获取微信数据,传递给后端
-
*/
-
static getCryptoData() {
-
let code =
"";
-
return
this.login()
-
.then(
data => {
-
code = data.code;
-
console.log(
"login接口获取的code:", code);
-
return
this.getUserInfo();
-
})
-
.then(
data => {
-
console.log(
"getUserInfo接口", data);
-
let obj = {
-
js_code: code,
-
};
-
return
Promise.resolve(obj);
-
})
-
.catch(
e => {
-
console.log(e);
-
return
Promise.reject(e);
-
})
-
};
-
-
/**
-
* 从后端获取openid
-
* @param {object} params
-
*/
-
static getMyOpenid(params) {
-
let url =
'https://xx.xxxxxx.cn/api/openid';
-
return
this.request(url, params,
"POST",
"application/x-www-form-urlencoded");
-
};
-
}
-
module.exports = Wechat;
2、修改小程序的app.js文件
-
let wechat =
require(
'./utils/wechat.js');
-
App({
-
onLaunch() {
-
this.getUserInfo();
-
},
-
getUserInfo() {
-
wechat.getCryptoData()
-
.then(
d => {
-
return wechat.getMyOpenid(d);
-
})
-
.then(
d => {
-
console.log(
"从后端获取的openid", d.data);
-
})
-
.catch(
e => {
-
console.log(e);
-
})
-
}
-
})
后端nodejs，是用的express命令行生成的项目框架，
1、创建common文件夹，创建utils文件，使用request模块请求接口，promise化request
-
const request =
require(
"request");
-
class Ut {
-
-
/**
-
* promise化request
-
* @param {object} opts
-
* @return {Promise<[]>}
-
*/
-
static promiseReq(opts = {}) {
-
return
new
Promise(
(resolve, reject) => {
-
request(opts, (e, r, d) => {
-
if (e) {
-
return reject(e);
-
}
-
if (r.statusCode !=
200) {
-
return reject(
`back statusCode：${r.statusCode}`);
-
}
-
return resolve(d);
-
});
-
})
-
};
-
-
};
-
-
module.exports = Ut;
2、新增路由，appId、secret在小程序的后台获取
-
router.post(
"/openid",
async (req, res) => {
-
const Ut =
require(
"../common/utils");
-
try {
-
console.log(req.body);
-
let appId =
"wx70xxxxxxbed01b";
-
let secret =
"5ec6exxxxxx49bf161a79dd4";
-
let { js_code } = req.body;
-
let opts = {
-
url:
`https://api.weixin.qq.com/sns/jscode2session?appid=${appId}&secret=${secret}&js_code=${js_code}&grant_type=authorization_code`
-
}
-
let r1 =
await Ut.promiseReq(opts);
-
r1 =
JSON.parse(r1);
-
console.log(r1);
-
res.json(r1);
-
}
-
catch (e) {
-
console.log(e);
-
res.json(
'');
-
}
-
})
结果：
这个返回结果没有unionid，按照官方的说法，需要在微信开放平台绑定小程序；
如果需要解密和数据校验，请跳转这里。
参考地址：
https://mp.weixin.qq.com/debug/wxadoc/dev/api/api-login.html
https://mp.weixin.qq.com/debug/wxadoc/dev/api/uinionID.html