使用循环问题托管 Web 服务器

Question

我正在尝试托管在 Cyclic 上配置了 API 的 server.js 文件，部署成功，但 URL 对任何端点调用返回状态 500。我在 github 页面上托管了 React 前端。我不知道缺少什么，也不知道为什么部署成功后它没有响应任何呼叫。是因为我没有将端点配置为 '/' 吗？

server.js代码：

const express = require('express')
const cors = require('cors')
require("dotenv").config()
const {getDb, dbConnect} = require('./db')
const app = express()


app.use(cors({origin: 'https://mygithubpage.github.io/'}))
app.use(express.json())

let db
const port = process.env.PORT || 6900;
dbConnect((error) => {
    if(!error) {
        app.listen(port, () => {
            console.log(`Now listening to port ${port}`)
        })
        db = getDb()
    }   
})

// Searching for email and password
app.post('/signIn', (req,res) => {
    
    const user = req.body

    db.collection('users')
    .findOne({email: user.email, password: user.password})
    .then(user => {
        res.status(200).json(user)
    })
    .catch(error => {
        res.status(500).json({error: 'user not found'})
    })
})

循环部署日志：

2023-04-02T20:00:47.283Z: [CYCLIC] cloning...
2023-04-02T20:00:48.776Z: From https://github.com/mygithubpage/movie-app
 * branch            ddd079a5bf40fbb8e440632fcdd91b584265c9cb -> FETCH_HEAD
2023-04-02T20:00:49.984Z: HEAD is now at ddd079a added node in package.json
2023-04-02T20:00:49.998Z: [CYCLIC] Building...
2023-04-02T20:00:50.023Z: Build Configuration:
  Root Path: /server
  Output Path: /
  Static Site: false
  Runtime: nodejs18.x
  Branch: main
  Ref: ddd079a5bf40fbb8e440632fcdd91b584265c9cb

2023-04-02T20:00:50.238Z: [CYCLIC] verifying...
2023-04-02T20:00:50.308Z: [CYCLIC] using: node:v18.15.0 npm:10.1.0 runtime:nodejs18.x
[CYCLIC] building from: /server
2023-04-02T20:00:50.317Z: [CYCLIC] installing dependencies from: package-lock.json
2023-04-02T20:00:56.440Z: 
added 110 packages in 6s
2023-04-02T20:00:56.456Z: [CYCLIC] running build if defined...
2023-04-02T20:00:56.950Z: [CYCLIC] pruning dev dependencies...
2023-04-02T20:00:57.746Z: 
removed 2 packages in 353ms
2023-04-02T20:00:57.773Z: [CYCLIC] packaging 109.36 MB...
2023-04-02T20:00:57.775Z: [CYCLIC] bundling from  ...
2023-04-02T20:01:02.914Z: [CYCLIC] done packaging
[CYCLIC] deploying...
2023-04-02T20:01:11.058Z: deployed ca-central-1 -  8.062s
2023-04-02T20:01:11.059Z: SUCCESS

took 24.1 seconds
api deployed at:
https://gleaming-plum-horse.cyclic.app

我尝试使用其他网站，如www.render.com，但每次超时后部署都会失败，并且启动服务“npm start”/“node server.js”的多个日志

每当我向服务器发送 GET/POST 请求时，都会收到此错误

2023-04-03 13:11:35.635: grep: /var/task/package.json: No such file or directory
2023-04-03 13:11:35.665: grep: /var/task/package.json: No such file or directory
ERROR: Cannot find entry point.
2023-04-03 13:11:42.344: 
          ERROR: Application process finished with status code 0 before starting a server

          Common causes/solutions for this include:

            - Server listen method not called. Verify server is listening on a port: "app.listen(process.env.PORT||3000)"
            - An error may have been caught without being logged. Verify try/catch blocks have appropriate logging.

server.js 环境在本地运行良好。

Answer 1

我认为你缺少app.listen()方法。

https://expressjs.com/en/starter/hello-world.html

上面的链接应该可以让您很好地了解缺少的内容，除非您在上面分享的代码片段已被截断。

const express = require('express');
const app = express();

app.get("/", (req, res) => {
    res.status(200).json( { msg: "Helloaaa" });
});

app.listen(7000, () => {
    console.log(`The app has started on PORT 7000`)
});

上面的代码片段也是一个示例，可能会指导您发现可能出现的错误。我们初始化 GET API，然后打开应用程序以侦听端口 7000。

如果没有该端口，应用程序就不会侦听任何端口，因此不会有响应。