milsosa/node-request-retry

Wrap NodeJS request module to retry http requests in case of errors

Request-retry

When the connection fails with one of ECONNRESET, ENOTFOUND, ESOCKETTIMEDOUT, ETIMEDOUT, ECONNREFUSED, EHOSTUNREACH, EPIPE, EAI_AGAIN or when an HTTP 5xx error occurrs, the request will automatically be re-attempted as these are often recoverable errors and will go away on retry.

Usage

Request-retry is a drop-in replacement for request but adds two new options maxAttempts and retryDelay. It also adds one property to the response, attempts.

var request = require('requestretry');

request({
  url: 'https://api.domain.com/v1/a/b'
  json:true,

  // The below parameters are specific to request-retry
  maxAttempts: 5,   // (default) try 5 times
  retryDelay: 5000,  // (default) wait for 5s before trying again
  retryStrategy: request.RetryStrategies.HTTPOrNetworkError // (default) retry on 5xx or network errors
}, function(err, response, body){
  // this callback will only be called when the request succeeded or after maxAttempts or on error
  if (response) {
    console.log('The number of request attempts: ' + response.attempts);
  }
});

Installation

Install with npm.

npm install --save requestretry

How to define your own retry strategy

/**
 * @param  {Null | Object} err
 * @param  {Object} response
 * @return {Boolean} true if the request should be retried
 */
function myRetryStrategy(err, response){
  // retry the request if we had an error or if the response was a 'Bad Gateway'
  return err || response.statusCode === 502;
}

request({
  url: 'https://api.domain.com/v1/a/b'
  json:true,
  retryStrategy: myRetryStrategy
}, function(err, response, body){
  // this callback will only be called when the request succeeded or after maxAttempts or on error
});

Modifying request options

You can access request's defaults method like so:

var request = require('requestretry').request.defaults({my: options});

Changelog

Copyright 2014, Francois-Guillaume Ribreau (npm@fgribreau.com)