double-stack

A modern implementation of long stack traces for Node.js based-on longjohn and superstack.

Features

• Written in ES2015
• Support for Node.js 4 and newer
• Support for source maps
• Support for EventEmitters
• Support for Promises
• Configurable stack limit and empty frame token
• Returns active handles (timers, servers, socket connections, child processes, etc)
  • For setTimeout() or setInterval(), double-stack adds the stack to the timer object

Installation

npm install double-stack

Usage

If you just want long stack traces:

import 'double-stack';
// or require('double-stack');

If you want to change options or get active handles:

import * as ds from 'double-stack';

ds.options.asyncTraceLimit = 5;

const handles = ds.getActiveHandles();

Options

ds.options.asyncTraceLimit (Number)

A positive integer that is greater than or equal to zero. Defaults to 10.

ds.options.emptyFrame (String)

A string to print representing an empty frame in the stack. Defaults to - x 50.

getActiveHandles()

Returns an object containing arrays of various handle types including: timers, sockets, servers, childProcesses, and other.

import * as ds from 'double-stack';

setTimeout(() => {}, 1000);

const handles = ds.getActiveHandles();
handles.timers.forEach(timer => {
    console.log(timer);

    // you can also do a clearTimeout(timer)
});

Production Use

According to the longjohn readme:

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.

Since double-stack is basically the same as longjohn, then the same is true for double-stack. With that said, I've been using longjohn in production command line tools for years without any issues. However, it's probably a completely different story when running a server such as an Express.js app.

References

double-stack wouldn't exist without the great work done by mattinsler/longjohn, defunctzombie/node-superstack, and tlrobinson/long-stack-traces. Each of these projects are licensed under the MIT license.

License

(The MIT License)

Copyright (c) 2016-2017 Chris Barber Copyright (c) 2012 Matt Insler Copyright (c) 2013 Roman Shtylman Copyright (c) 2011 Thomas Robinson [email protected]

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.