Node.js debugging in VS Code with Nodemon

By Kenneth Auchenberg

This recipe shows how to use the built-in Node Debugger to debug Nodejs applications that use Nodemon.

Nodemon is a utility that will monitor for any changes in your source and automatically restart your server, and our Node debugger for VS Code supports automatic re-attaching to the Node process.

We recommend that you use our Node debugger in an attach configuration that's attaching to your Node process running.

Getting Started

1. Make sure to have the latest version of VS Code installed.

2. This guide assumes that you are using the official sample app nodejs-shopping-cart. Clone the repo to get started

   git clone git@github.com:gtsopour/nodejs-shopping-cart.git
   cd nodejs-shopping-cart
   npm install
   code .
   

Configure VS Code debugging with a launch.json file

1. Click on the Debugging icon in the Activity Bar to bring up the Debug view. Then click on the gear icon to configure a launch.json file, selecting Node for the environment:

   

2. Replace content of the generated launch.json with the following two configurations:

   {
       "version": "0.2.0",
       "configurations": [
           {
               "type": "node",
               "request": "launch",
               "name": "Node: Nodemon",
               "runtimeExecutable": "npm",
               "runtimeArgs": ["start"],
               "outputCapture": "std",
           },
       ]
   }

Start your node app via your new NPM script

The next step is to start your Node app via your new npm run debug script. We can highly recommend using the integrated console in VS Code.

Debugging the Node process

1. Go to the Debug view, select the 'Node: Nodemon' configuration, then press F5 or click the green play button.

2. VS Code should now attempt to start your Meteor app.

3. Go ahead and set a breakpoint in routes/index.js on line 10 within the route handler function.

4. Open your favorite browser and go to http://localhost:3000

5. Your breakpoint should now be hit.

6. Try to make a change to routes/index.js.

7. Nodemon should kick in after the change, and you should see VS Code re-attach to the newly spawned Node process automatically.

8. Party 🎉🔥