从 github node.js 部署应用程序错误 heroku

Question

Heroku 从 github 存储库部署时显示应用程序错误，这里是 package.json

{
  "name": "tinder-backend",
  "version": "1.0.0",
  "description": "",
  "main": "server.js",
  "type": "module",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "start": "node server.js"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "cors": "^2.8.5",
    "express": "^4.17.1",
    "mongoose": "^5.11.15"
  }
}

但它总是在 heroku 上显示应用程序错误我添加了 gitignore 以排除 node_modules 这是我的代码（不是我的，而是从 youtube 学习 express --> server.js）：

import express from 'express'
import mongoose from 'mongoose'

import Cors from 'cors'
import Cards from './dbCards.js'

// App Config
const app = express();
const port = process.env.port || 8001

const connection_url = `mongodb://admin:<hidden>@cluster0-shard-00-00.7vrlv.mongodb.net:27017,cluster0-shard-00-01.7vrlv.mongodb.net:27017,cluster0-shard-00-02.7vrlv.mongodb.net:27017/<hidden>?ssl=true&replicaSet=atlas-p4781z-shard-0&authSource=admin&retryWrites=true&w=majority`
//Middlewares
app.use(express.json())
app.use(Cors())
//DB config
mongoose.connect(connection_url,{
    useNewUrlParser: true,
    useCreateIndex: true,
    useUnifiedTopology: true,
})
//api ENDPOINTS
app.get('/',(req,res)=>{
    res.status(200).send('Hello world')
});

app.post('/tinder/card',(req,res) => {
    const dbCard = req.body;
    Cards.create(dbCard,(err,data) => {
        if(err){
            res.status(500).send(err)
        }
        else{
            res.status(201).send(data)
        }

    })
});

app.get('/tinder/card',(req,res) => {
    const dbCard = req.body;
    Cards.find((err,data) => {
        if(err){
            res.status(500).send(err)
        }
        else{
            res.status(200).send(data)
        }

    })
});
//listener
app.listen(port,()=> console.log(`listening on localhost:${port}`));

这在本地机器上完美运行，初学者在这里任何帮助将不胜感激

这是我在活动中看到的日志：

-----> Building on the Heroku-20 stack
-----> Node.js app detected
       
-----> Creating runtime environment
       
       NPM_CONFIG_LOGLEVEL=error
       NODE_VERBOSE=false
       NODE_ENV=production
       NODE_MODULES_CACHE=true
       
-----> Installing binaries
       engines.node (package.json):  unspecified
       engines.npm (package.json):   unspecified (use default)
       
       Resolving node version 14.x...
       Downloading and installing node 14.15.4...
       Using default npm version: 6.14.10
       
-----> Restoring cache
       - node_modules
       
-----> Installing dependencies
       Installing node modules
       added 83 packages in 2.08s
       
-----> Build
       
-----> Caching build
       - node_modules
       
-----> Pruning devDependencies
       audited 83 packages in 1.059s
       
       2 packages are looking for funding
         run `npm fund` for details
       
       found 0 vulnerabilities
       
       
-----> Build succeeded!
-----> Discovering process types
       Procfile declares types     -> (none)
       Default types for buildpack -> web
-----> Compressing...
       Done: 34.2M
-----> Launching...
       Released v6

Answer 1

我的错误是const port = process.env.port || 8001这一行，应该是process.env.PORT，端口大写，成功浪费了我的时间

Answer 2

如果您正确遵循 Haruko 网站上的 Heroku 部署指南，那么您必须确保已将 IP 地址作为白名单添加到您的 MongoDB 帐户。有时人们会遇到 IP 地址的问题，因为当您不将 IP 地址添加到 MongoDB 帐户时，Heroku 无法启动服务器。并确保您在项目根目录中添加了 Heroku procfile。