---
tags: ironhack
---

[:fr: version française](https://hackmd.io/s/BJ60qRS4E)

Node.js debugger into VS Code
===

## `node --inspect`

To enable Node's debug mode, we should execute `node` with the [`--inspect`](https://nodejs.org/api/debugger.html) flag.

Let's add that flag to our `npm run dev` script into `package.json` file, generated by [`irongenerate`](https://www.npmjs.com/package/iron-generator):

    "dev": "DEBUG=starter-code:* nodemon --inspect ./bin/www"

:::info
:bulb: Without having to modify that line, we can also pass the flag by executing the command `npm run dev -- --inspect` but it's longer :smiley: and we have to remember it every time (see the [npm-run-script](https://docs.npmjs.com/cli/run-script.html) doc about.)
:::

## `Auto Attach`

In VS Code's preferences, we set the `Node: Auto Attach` setting to `on`:

## Debug now🐛

**From a VS Code terminal**, we now launch the command `npm run dev`:

> The command outputs: `Debugger listening on port 9229.`

We can now set some breakpoints, by clicking on the line we want to debug:

> 🔴 The red point to the left of the line 71 indicates that a breakpoint is now set to.

---

When a request will call that line of code, the debugger will pause the program and will allow us to inspect our variables values, do some step-by-step... etc:


## devTools alternative

If we don't want to use VS Code to debug, Chrome devTools is also possible:

- Go to URL: [`chrome://inspect`](chrome://inspect)
- then click on the `inspect` link on the corresponding remote target :