为什么在Heroku中连接不上Mongodb服务器？

Question

I want to develop ToDoApp with React and MongoDb. I created database in MongoDb Atlas and entegrated to my react. In local, everything is working but in heroku, I got error.

const express = require('express');
const app = express();
const bodyParser = require('body-parser');
const cors = require('cors');
const mongoose = require('mongoose');
const todoRoutes = express.Router();

let Todo = require('./todo.model');

app.use(cors());
app.use(bodyParser.json());

mongoose.connect('mongodb+srv://<MyUsername>:<MyPassword>@asnus-sql-5enaw.mongodb.net/todolist', { useNewUrlParser: true });
const connection = mongoose.connection;

connection.once('open', function() {
    console.log("MongoDB database connection established successfully");
})

...
...
...

...
...
...
  "eslintConfig": {
    "extends": "react-app"
  },
  "proxy":"http://localhost:4000"
}

This is my app in heroku, you can see 'Failed to load resource: net::ERR_CONNECTION_REFUSED' error in console: https://asnus-todolist.herokuapp.com

And if you want you can see my code in github: https://github.com/sametsunman/ToDoList

Answer 1

it may have to do with your string connection:

mongoose.connect('mongodb+srv://<MyUsername>:<MyPassword>@asnus-sql-5enaw.mongodb.net/todolist', { useNewUrlParser: true });

Check that your username and password are written without brackets like this example taken from here

client = "mongodb+srv://kay:myRealPassword@cluster0.mongodb.net/test?w=majority"