Search code examples
node.jsdebuggingwebstormbreakpoints

Do not know how to start debugging a Node.js code in JetBrains WebStorm

I am trying to learn to debug a Node.js code in WebStorm. The code is the simple "Getting Started" code from here:

const http = require('http');

const hostname = '127.0.0.1';
const port = 3000;

const server = http.createServer((req, res) => {
  res.statusCode = 200;
  res.setHeader('Content-Type', 'text/plain');
  res.end('Hello World\n');
});

server.listen(port, hostname, () => {
  console.log(`Server running at http://${hostname}:${port}/`);
});

The above code works correctly after I ran node app.js at command line and visited http://localhost:3000. Next I tried to debug it locally in JetBrains WebStorm following instructions here. This is the debug configuration of Node.js application in WebStorm:

enter image description here

I clicked the bug icon to run the Node.js code under debugging mode. This is the output:

"C:\Program Files (x86)\JetBrains\WebStorm 10.0.3\bin\runnerw.exe" "C:\Program Files\nodejs\node.exe" --debug-brk=24163 --nolazy --inspect app.js
Debugger listening on ws://127.0.0.1:24163/bffa51bd-74bd-4257-8174-2c8ab3768e17
For help see https://nodejs.org/en/docs/inspector

I guess that it is equivalent to running the "node app.js" command. The instruction says I need to "Perform the steps that will trigger the execution of the code with the breakpoints." I guess that means I open the URL "http://localhost:3000" in browser to send a request to the web server that the app.js is implementing, and I did it. I have set up breakpoints on every line of the source app.js and I expected that the breakpoints should be hit somewhere in the source, but the browser reported an "Unable to connect" error and nothing happened in WebStorm -- no breakpoint is hit. I have checked the instructions but could not figure out what I am missing. Could you please help me with this problem? If you need more information please let me know. Thanks a lot!

PS: app.js is in the ...\test folder.

==Edit:==

PS2: The browser can print "Hello world" just because "node app.js" is still running. After I terminated it, the browser reports "Unable to connect". So that means the URL does not know how to connect to the webserver launched by WebStorm debugger. Is the port wrong?

PS3: This is what returns from http://localhost:31496/json/list (the port number changes in every debugging session). Hope it can help troubleshooting.

description "node.js instance"
devtoolsFrontendUrl "chrome-devtools://devtools/bundled/inspector.html?experiments=true&v8only=true&ws=127.0.0.1:31496/0f03cac0-648f-4c13-9cb9-39bb5e3a81a6"
faviconUrl  "https://nodejs.org/static/favicon.ico"
id  "0f03cac0-648f-4c13-9cb9-39bb5e3a81a6"
title   "app.js"
type    "node"
url "file://E:..._test_app.js"
webSocketDebuggerUrl    "ws://127.0.0.1:31496/0f03cac0-648f-4c13-9cb9-39bb5e3a81a6"
Solution

  • As far as I can see, you are using webStorm 10. It's quite old and doesn't support new debugger protocol introduced in recent Node.js updates.

    Please downgrade Node.js to v. 4.x (at least) or, better, upgrade Webstorm to 2017.3