微信公众号开发中最常遇到的就是调用接口时候需要有API的access-token（非网页授权的access-token），有了这个token之后，才可以发生模板消息等。
这里的做法主要是用nodejs的later模块是实现每隔一个小时去微信上刷新一次token，获取到最新的access-token之后保存到数据库之中。其他的业务需要用到这个token，再去数据库中抓取最新的access-token。
WechatTokenTask.js代码如下：
1 var later = require(‘later‘), 2 mysql = require(‘mysql‘), 3 https = require(‘https‘), 4 moment = require(‘moment‘); 5 6 var connection = mysql.createConnection({ 7 host: ‘112.74.***.*‘, 8 port: 3306, 9 user: ‘root‘, 10 password: ‘****‘, 11 database: ‘lz***‘ 12 }); 13 14 var appid = "wx082bc0*********", 15 appsecret = "d3c24a08d03b4*****************"; 16 17 // will fire every 5 minutes 18 //var textSched = later.parse.text(‘every 1 min‘); 19 var textSched = later.parse.cron(‘0 */1 * * *‘); 20 //var textSched = later.parse.text(‘every 1 hours‘); 21 //var occurrences = later.schedule(textSched).next(10); 22 23 //for (var i = 0; i < 10; i++) { 24 // console.log(occurrences[i]); 25 //} 26 27 // execute logTime for each successive occurrence of the text schedule 28 later.setInterval(dotask, textSched); 29 30 setTimeout(dotask, 100);//fire when app start run 31 32 function dotask() { 33 var options = { 34 hostname: ‘api.weixin.qq.com‘, 35 path: ‘/cgi-bin/token?grant_type=client_credential&appid=‘ + appid + ‘&secret=‘ + appsecret 36 }; 37 var req = https.get(options, function (res) { 38 //console.log("statusCode: ", res.statusCode); 39 //console.log("headers: ", res.headers); 40 var bodyChunks = ‘‘; 41 res.on(‘data‘, function (chunk) { 42 bodyChunks += chunk; 43 }).on(‘end‘, function () { 44 var body = JSON.parse(bodyChunks); 45 //console.dir(body); 46 if (body.access_token) { 47 var access_token = body.access_token; 48 saveAccessToken(access_token); 49 //console.log(access_token); 50 } else { 51 console.dir(body); 52 } 53 }) 54 }); 55 56 req.on(‘error‘, function (e) { 57 console.log(‘ERROR: ‘ + e.message); 58 }); 59 } 60 61 /* Save access token to DB*/ 62 function saveAccessToken(accessToken) { 63 var postData = { 64 AccessToken: accessToken, 65 Date: moment().format(‘YYYY-MM-DD HH:mm:ss‘) 66 }; 67 68 connection.connect(); 69 connection.query(‘INSERT INTO `WeChatToken` SET ?‘, postData, function (err, result) { 70 // Neat! 71 if (err) { 72 console.log(JSON.stringify(err)); 73 connection.end(); 74 } 75 76 if (result && result.affectedRows == 1) { 77 console.log("success"); 78 } 79 }); 80 connection.end(); 81 }
table scheme如下:
CREATE TABLE `WeChatToken` ( Id INT NOT NULL AUTO_INCREMENT PRIMARY KEY, `Date` DATETIME NOT NULL , AccessToken VARCHAR(255) NOT NULL ) ;
业务里可以用通过以下语法获取最新有效的access-token
SELECT AccessToken FROM WeChatToken ORDER BY Id DESC LIMIT 1;
该服务发布在CentOS 7, 用PM2管理。
pm2 start lzone6/WechatTokenTask.js -i 1 --name GetTokenService