Package Exports

backoff

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (backoff) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

Exponential backoff implementation for Node.js

An exponential backoff implementation for Node.js.

Installation

npm install backoff

Usage

In order to use backoff, require backoff.

var Backoff = require('backoff');

Backoff inherits from EventEmitter. One can listen for backoff completion by listening for backoff events. Registered handlers will be called with the current backoff number and delay.

var backoff = new Backoff({
    initialTimeout: 10,
    maxTimeout: 1000
});

backoff.on('backoff', function(number, delay) {
    console.log(number + ' ' + delay + 'ms');

    if (number < 10) {
        backoff.backoff();
    }
});

backoff.backoff();

The previous example would print:

1 10ms
2 20ms
3 40ms
4 80ms
5 160ms
6 320ms
7 640ms
8 1000ms
9 1000ms
10 1000ms

API

new Backoff([options])

Construct a new backoff object.

options is an object with the following defaults:

options = {
    initialTimeout: 100,
    maxTimeout: 10000
};

With these values, the timeout delay will exponentially increase from 100ms to 1000ms.

backoff.backoff()

Start a backoff operation, doubling the previous timeout.

Returns true on success and false if a backoff was already in progress.

backoff.reset()

Reset the backoff object state. If a backoff operation is in progress when called, it will be stop. After reset, a backoff instance can be reused.

Event: 'backoff'

number: number of backoff since last reset
delay: current backoff delay

Emitted on backoff completion.

Event: 'reset'

Emitted when a backoff instance is reset.

License

This code is free to use under the terms of the MIT license.