How to debug node js app with breakpoints and everything?

user_189673 0
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I've installed node-inspector just to find out that it doesn't support breakpoints :| What's the point in it at all, bearing in mind that on big part node code is asynchronous and you simply cannot follow it step by step?..

I'm definitely missing a point here...

Anyway to debug node code with breakpoints and everything?

node-inspector v8 node.js debugging
5 Answers

(For Node 8 and later)

Node.js has a built-in debugger. Normally you can turn on the debugger in two ways:

  1. Start your Node.js app or script with the --inspect or --inspect-brk switch. For example:

    $ node.js --inspect index.js

(Note: --inspect-brk breaks before user code starts)

  1. If for some reason you cannot start your Node.js app or script with the --inspect switch, you can still instruct the Node.js process to start listening for debugging messages by signalling it with SIGUSR1 (on Linux and OS X). For Node 8 and later it will activate the Inspector API, same as the --inspect switch

    $ kill -sigusr1 23485

(Note: you need to replace 23485 with your own Node.js process ID)

With the debugger turned on, you can open the Google Chrome browser, and type in the address bar chrome://inspect

Then you should see an entry listed under "Remote Target". Go ahead and click "inspect".

Now you can set breakpoints and start debugging your code.

Reference:

  1. https://nodejs.org/en/docs/guides/debugging-getting-started/
  2. Related issue on stackoverflow: Chrome Devtools Dedicated Node.js Inspector not stopping at breakpoints
user_27003560

To debug a Node.js application, one can use the debugging built-in method:

(1) Insert debugger; statement where you want to insert a break point
(2) Run the file with command $ node inspect <file name>
(3) Use a key for example, c to continue to next break point

You can even debug values associated to variables at that break point by typing repl. For more information, Please check the official guide.

user_82050850

Have you tried using nodemon library? it can be found here.

For development purposes you could start the app running nodemon. I have this script:

"dev": "nodemon --inspect src/index.js"

It will break any time a debugger statement is reached in the code. To open the console where you can see the server code, open the console in chrome and click on the nodejs icon:enter image description here

It also helps you refreshing the server every time you save any file on the server.

Let me know if it works!

user_13613350
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