Bugger NPM | npm.io

bugger

Warning: Experimental

bugger provides Chrome Devtools bindings for node. It integrates tightly with Chrome which means two things:

It attempts to fully support the usual Devtools experience, including workspaces and profiling tools.
It may break at any moment because Chrome moves fast.

Installation

npm install -g bugger

Usage

Start the script process

Start example/alive.js in debug mode:

bugger example/alive.js

Pass parameters to the script:

# This will be interpreted as a port paramter for alive.js
bugger example/alive.js --port=3000
# This will be interpreted as a port paramter for bugger itself
bugger --port=3000 example/alive.js

Pass V8 options (or advanced node options):

node --trace_gc $(which bugger) example/alive.js

Open the devtools

The correct URL will be written to the output. It should look similar to this:

chrome-devtools://devtools/bundled/devtools.html?ws=127.0.0.1:8058/websocket

You can also open chrome://inspect if you started Chrome with --remote-debugging-targets=localhost:8058. The process should pop up on that page almost immediately.

Options:

-v, --version: Print version information
-h, --help: Show usage help
-p, --port: The devtools protocol port to use, default: 8058
-b, --brk: Pause on the first line of the script

Features

Console Tab

Basic support for console API
Evalute expressions in the console
Fully featured repl when not paused (including require)
Parts of the Command Line API supported

Sources Tab

Step-by-step debugging
Variable introspection
Live edit the running JavaScript code and persist it using workspaces (really just a Devtools feature)
Break on uncaught exception
Uses existing source maps (e.g. created via babel --source-maps or coffee --map)
Forked modules show up as worker threads. This includes modules forked via cluster.

Known Issues

For babel-core/register and coffee-script/register, editing the files doesn't work #48

Network Tab

Monitor outgoing http(s) requests your script does
Timing of requests, including connect times etc.

Timeline Tab

GC events
Basic heap usage graphs

Known Issues

The timeline tab doesn't do anything useful right now. In future it should show (#47):
- console.{time, timeEnd, timeStamp}
- Network request
- Heap usage over time
- Profiling data