如何在package.json的scripts中配置本地启动MongoDB与Nodemon？

Absolutely! You can ditch the copy-pasting from text files by setting up custom npm scripts in your package.json—this will let you start both MongoDB and Nodemon with a single command. Let’s break this down into easy steps:

Step 1: Install a tool to run multiple commands concurrently #

Since we need to start both MongoDB and Nodemon at the same time, we’ll use concurrently (a popular package for running multiple scripts in parallel). Install it as a dev dependency:

npm install --save-dev concurrently

Step 2: Configure your package.json scripts #

Open your package.json file and add the following to the "scripts" section. Note that the MongoDB command might vary slightly based on your operating system:

For Mac/Linux: #

"scripts": {
  // Start MongoDB (adjust the --dbpath if your data directory is elsewhere)
  "start:mongo": "mongod --dbpath ./data/db",
  // Start Nodemon (replace "server.js" with your actual entry file)
  "start:server": "nodemon server.js",
  // Run both scripts at once
  "dev": "concurrently \"npm run start:mongo\" \"npm run start:server\""
}

For Windows: #

The only difference is the file path syntax for the MongoDB data directory:

"scripts": {
  "start:mongo": "mongod --dbpath .\\data\\db",
  "start:server": "nodemon server.js",
  "dev": "concurrently \"npm run start:mongo\" \"npm run start:server\""
}

Key Notes: #

• MongoDB Data Directory: If you don’t have a data/db folder in your project root, create it first:
  • Mac/Linux: mkdir -p data/db
  • Windows: mkdir data\db
• MongoDB as a System Service: If you installed MongoDB as a system service (common on Windows), replace the start:mongo command with net start MongoDB (to launch the service) or just mongod if it’s already in your system PATH.
• Entry File: Make sure to replace "server.js" with your actual server entry file (like app.js or index.js).

Step 3: Run your automated workflow #

Now you can start both services with a single terminal command:

npm run dev

Concurrently will handle running both MongoDB and Nodemon in the same terminal, showing output from both processes. If you need to stop them, just press Ctrl + C once to terminate both scripts.

Troubleshooting Common Hiccups #

• MongoDB won’t start: Double-check the --dbpath path—make sure the folder exists and MongoDB has permission to access it. If you get a "command not found" error, ensure MongoDB is added to your system PATH.
• Nodemon can’t connect to MongoDB: Sometimes MongoDB takes a second to finish initializing. If you run into connection errors, install the wait-on package (npm install --save-dev wait-on) to delay Nodemon until MongoDB is ready, then update your dev script:

  "dev": "npm run start:mongo & wait-on mongodb://localhost:27017 && npm run start:server"
  

  (This syntax works best on Mac/Linux; for Windows, you might need to adjust to use batch file logic or a cross-platform alternative.)

内容的提问来源于stack exchange，提问作者Tyler C