debugging-main-process.md

Debugging the main process

The devtools of browser window can only debug the renderer process scripts. (I.e. the web pages.) In order to provide a way to debug the scripts of the main process, Electron has provided the --debug and --debug-brk switches.

Command line switches

--debug=[port]

When this switch is used Electron would listen for V8 debugger protocol messages on port, the port is 5858 by default.

--debug-brk=[port]

Like --debug but pauses the script on the first line.

Use node-inspector for debugging

Note: Electron uses node v0.11.13, which currently doesn't work very well with node-inspector, and the main process would crash if you inspect the process object under node-inspector's console.

1. Start the node-inspector server

$ node-inspector

2. Enable debug mode for Electron

You can either start Electron with a debug flag like:

$ electron --debug=5858 your/app

or, to pause your script on the first line:

$ electron --debug-brk=5858 your/app

3. Load the debugger UI

Open http://127.0.0.1:8080/debug?ws=127.0.0.1:8080&port=5858 in the Chrome browser.