mongoose.connect()，第一个参数应该是 String，接收未定义

Question

我正在尝试为测试目的设置测试数据库，但它不起作用。

我正在尝试使用猫鼬连接到 MongoDB，但在连接错误中发现问题显示：

 throw new MongooseError('The `uri` parameter to `openUri()` must be a ' +
    ^
MongooseError: The `uri` parameter to `openUri()` must be a string, got "undefined". Make sure the first parameter to `mongoose.connect()` or `mongoose.createConnection()`is a string.
    at new MongooseError (/media/abhigyan/ABHI/programming/node js/Practice/On my Own/Todo/node_modules/mongoose/lib/error/mongooseError.js:11:11)
    at NativeConnection.Connection.openUri (/media/abhigyan/ABHI/programming/node js/Practice/On my Own/Todo/node_modules/mongoose/lib/connection.js:424:11)
    at Mongoose.connect (/media/abhigyan/ABHI/programming/node js/Practice/On my Own/Todo/node_modules/mongoose/lib/index.js:230:15)
    at Object.<anonymous> (/media/abhigyan/ABHI/programming/node js/Practice/On my Own/Todo/server/db/mongoose.js:5:10)
    at Module._compile (module.js:635:30)
    at Object.Module._extensions..js (module.js:646:10)
    at Module.load (module.js:554:32)
    at tryModuleLoad (module.js:497:12)
    at Function.Module._load (module.js:489:3)
    at Module.require (module.js:579:17)
    at require (internal/module.js:11:18)
    at Object.<anonymous> (/media/abhigyan/ABHI/programming/node js/Practice/On my Own/Todo/server/models/Todo.js:1:82)
    at Module._compile (module.js:635:30)
    at Object.Module._extensions..js (module.js:646:10)
    at Module.load (module.js:554:32)
    at tryModuleLoad (module.js:497:12)
    at Function.Module._load (module.js:489:3)
    at Module.require (module.js:579:17)
    at require (internal/module.js:11:18)
    at Object.<anonymous> (/media/abhigyan/ABHI/programming/node js/Practice/On my Own/Todo/server/tests/server.test.js:4:16)
    at Module._compile (module.js:635:30)
    at Object.Module._extensions..js (module.js:646:10)
    at Module.load (module.js:554:32)
    at tryModuleLoad (module.js:497:12)
    at Function.Module._load (module.js:489:3)
    at Module.require (module.js:579:17)
    at require (internal/module.js:11:18)
    at /media/abhigyan/ABHI/programming/node js/Practice/On my Own/Todo/node_modules/mocha/lib/mocha.js:250:27
    at Array.forEach (<anonymous>)
    at Mocha.loadFiles (/media/abhigyan/ABHI/programming/node js/Practice/On my Own/Todo/node_modules/mocha/lib/mocha.js:247:14)
    at Mocha.run (/media/abhigyan/ABHI/programming/node js/Practice/On my Own/Todo/node_modules/mocha/lib/mocha.js:576:10)
    at Object.<anonymous> (/media/abhigyan/ABHI/programming/node js/Practice/On my Own/Todo/node_modules/mocha/bin/_mocha:637:18)
    at Module._compile (module.js:635:30)
    at Object.Module._extensions..js (module.js:646:10)
    at Module.load (module.js:554:32)
    at tryModuleLoad (module.js:497:12)
    at Function.Module._load (module.js:489:3)
    at Function.Module.runMain (module.js:676:10)
    at startup (bootstrap_node.js:187:16)
    at bootstrap_node.js:608:3
error Command failed with exit code 1.

我正在传递一个有效的字符串，但它不起作用！

 const mongoose = require('mongoose');

mongoose.Promise = global.Promise;
mongoose.connect(process.env.MONGODB_URI, err => {
    if(err)
        console.log(err);
    }
);

module.exports = {
    mongoose
};

这是运行 mocha 的脚本：

 export NODE_ENV='test' && mocha server/**/*.test.js

下面是配置代码：

 const config = require('./config.json');

const env = process.env.NODE_ENV.toString() || 'development';

if(env === 'test' || env === 'development') {
    const envConfig = config[env];
    Object.keys(envConfig).forEach(key => {
        process.env[key] = envConfig[key];
    });
};

console.log(env);

这是 config.json 文件：

 {
    "test": {
        "PORT": 3000,
        "MONGODB_URI": "mongodb://localhost:27017/TodoTest"
    },
    "development": {
        "PORT": 3000,
        "MONGODB_URI": "mongodb://localhost:27017/Todo"
    }
}

谢谢您的帮助！

原文由 abhigyan nayak 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 1

我认为您错过了导入 env 文件。

 require('dotenv').config({ path: 'ENV_FILENAME' });

原文由 Oni 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 2

要从 .env 文件中读取，您必须安装 dotenv（npm i dotenv / yarn add dotenv），然后将其添加到您的文件之上。

const dotenv = require("dotenv");

dotenv.config();

原文由 ASHISH R 发布，翻译遵循 CC BY-SA 4.0 许可协议