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Long stack traces for node.js inspired by
CoffeeScript JavaScript
Branch: master

Merge pull request #48 from drauggres/master

big update. please check twice.
latest commit d5d54f1351
@mattinsler authored


Long stack traces for node.js with configurable call trace length


I wrote this while trying to add long-stack-traces to my server and realizing that there were issues with support of EventEmitter::removeListener. The node HTTP Server will begin to leak callbacks and any of your own code that relies on removing listeners would not work as anticipated.

So what to do... I stole the code and rewrote it. I've added support for removeListener along with the ability to cut off the number of async calls the library will trace. I hope you like it!

Please thank tlrobinson for the initial implementation!

Production Use

Longjohn collects a large amount of data in order to provide useful stack traces. While it is very helpful in development and testing environments, it is not recommended to use longjohn in production. The data collection puts a lot of strain on V8's garbage collector and can greatly slow down heavily-loaded applications.


Just npm install it!

$ npm install longjohn


To use longjohn, require it in your code (probably in some initialization code). That's all!

if (process.env.NODE_ENV !== 'production'){

// ... your code


Limit traced async calls

longjohn.async_trace_limit = 5;   // defaults to 10
longjohn.async_trace_limit = -1;  // unlimited

Change callback frame text

longjohn.empty_frame = 'ASYNC CALLBACK';  // defaults to '---------------------------------------------'
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