详解微信小程序-获取用户session_key,openid,unionid - 后端为nodejs

 /** * 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; 

 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); }) } }) 

 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; 

 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(''); } })