如何将NodeJS App部署到Heroku？

Question

我正在用NodeJS创建一个聊天应用程序，我想部署到Heroku。 但是，我收到一个错误： An error occurred in the application and your page could not be served. If you are the application owner, check your logs for details. An error occurred in the application and your page could not be served. If you are the application owner, check your logs for details. 通过使用Github部署。 有人知道发生了什么吗？

这是一些代码，看我做了什么。

    {
  "name": "chat",
  "version": "0.0.0",
  "private": true,
  "scripts": {
    "start": "node ./lib/index.js",
    "test": "jasmine"
  },
  "dependencies": {
    "express": "~4.13.1",
    "firebase": "^3.9.0",
    "request-promise": "^2.0.1",
    "socket.io": "^1.4.5"
  },
  "devDependencies": {
    "jasmine-sinon": "^0.4.0",
    "jscs": "^2.11.0",
    "proxyquire": "^1.7.4",
    "rewire": "^2.5.1",
    "sinon": "^1.17.3"
  }
}

index.js（服务器）

    var express = require('express');
var app = express();
var path = require('path');
var http = require('http').Server(app);
var io = require('socket.io')(http);

var routes = require('./routes');
var chats = require('./chat');



app.use(express.static(path.join(__dirname, '../public')));

routes.load(app);
chats.load(io);


var port = process.env.PORT || 3000;
app.listen(port);
console.log('Server is listening at port:' + port); 

Answer 1

我让该应用程序在Heroku中运行。 代码中的问题是，您没有为heroku设置正确的端口。 在您提供的代码中，通过执行以下操作来设置正确的端口

var port = process.env.PORT || 3000;

但是，在您的GitHub项目中，您将端口硬编码为3000

http.listen(3000, function () {
  console.log('listening on *:3000');
});

相反，您想要做的是允许Heroku定义端口或将其默认设置为3000，以便进行开发。

var process = require('process');

var port = process.env.PORT || 3000;
http.listen(port, function() {
  console.log("Server is listening on port: " + port);
});

完成后，部署到Heroku，您应该会看到您的应用程序正在运行。