我已经在Google Cloud上创建了一个MySQL数据库,希望从另一个运行在Google Cloud上的节点Web应用程序中访问它。首先我在本地计算机上测试连接,当我在本地运行以下代码时,可以成功建立与我的数据库的连接并查看其中的数据。
'use strict';
// [START app]
const express = require('express');
const bodyParser = require('body-parser');
const path = require('path');
const app = express();
const mysql = require('mysql');
var connection = mysql.createConnection({
host : 'Cloud SQL IP',
user : 'username',
password : 'password',
database : 'db_name'
});
// parse application/x-www-form-urlencoded
app.use(bodyParser.urlencoded({ extended: false }))
// parse application/json
app.use(bodyParser.json())
// Make globals.js accessible
app.use(express.static(__dirname + '/'));
app.get('/', (req, res) => {
connection.connect();
connection.query('SELECT * FROM Users', function (error, results, fields) {
if (error) throw error;
console.log(results);
});
connection.end();
res.status(200).send('Hello World!');
});
app.get('/login', (req, res) => {
res.status(200).send();
});
// [START server]
const PORT = process.env.PORT || 8080;
app.listen(PORT, () => {
console.log(`App listening on port ${PORT}`);
console.log('Press Ctrl+C to quit.');
});
// [END app]
然而,当我在我的Google应用引擎上运行相同的代码(无论是在端口8080上进行调试还是完全部署在https://myapp.appspot.com上),我会收到以下超时错误:
{ Error: connect ETIMEDOUT
at Connection._handleConnectTimeout (/home/megan_cooper2900/project/node_modules/mysql/lib/Connection.js:419:13)
at Socket.g (events.js:292:16)
at emitNone (events.js:86:13)
at Socket.emit (events.js:185:7)
at Socket._onTimeout (net.js:338:8)
at ontimeout (timers.js:386:14)
at tryOnTimeout (timers.js:250:5)
at Timer.listOnTimeout (timers.js:214:5)
--------------------
at Protocol._enqueue (/home/megan_cooper2900/project/node_modules/mysql/lib/protocol/Protocol.js:145:48)
at Protocol.handshake (/home/megan_cooper2900/project/node_modules/mysql/lib/protocol/Protocol.js:52:23)
at Connection.connect (/home/megan_cooper2900/project/node_modules/mysql/lib/Connection.js:130:18)
at app.get (/home/megan_cooper2900/journeyma/app.js:31:13)
at Layer.handle [as handle_request] (/home/megan_cooper2900/project/node_modules/express/lib/router/layer.js:95:5)
at next (/home/megan_cooper2900/project/node_modules/express/lib/router/route.js:137:13)
at Route.dispatch (/home/megan_cooper2900/project/node_modules/express/lib/router/route.js:112:3)
at Layer.handle [as handle_request] (/home/megan_cooper2900/project/node_modules/express/lib/router/layer.js:95:5)
at /home/megan_cooper2900/project/node_modules/express/lib/router/index.js:281:22
at Function.process_params (/home/megan_cooper2900/project/node_modules/express/lib/router/index.js:335:12)
errorno: 'ETIMEDOUT',
code: 'ETIMEDOUT',
syscall: 'connect',
fatal: true }
为什么这个在Google App Engine应用程序上无法运行?