repeatable-request

To repeat a request until a condition is met. Used for retrying request whenever a retryable error is raised.

Installation

$ npm install --save repeatable-request

or with yarn

$ yarn add --dev repeatable-request

Usage

var repeatableRequest = require('repeatable-request');

var sendRequest = function() {
}

// Arguments are: contextArgs, args, done
repeatableRequest({
  sendRequest: sendRequest, // Required
  isRetryable: function (error, data) {
    // You can put any check here, Return true to sendRequest again
    return error.retryable === true;
  },
  backoffRange: {
    start: 200,
    end: 500,
  },
  maxRetryCount: 2,
}, { key: 'arguments passed as first parameter to sendRequest' }, function(error, done) {
  console.log(error, done);
});

Options

Various options can be passed to the first argument of repeatableRequest.

sendRequest (Required)

Method sending request with callback pattern signature

function(args, done);

repeatableRequest takes following arguments:

• contextArgs
• args
• done

Out of these args and done are passed to sendRequest method

isRetryable (Optional)

A function in format function(error, data) {}. If this method returns true then sendRequest is called again. Default:

function(error) {
  return error && error.retryable === true;
}

backoffRange { start, end } (Optional)

An object determining minimum and maximum time in milliseconds library should wait before retrying. Any random value b/w start and end is used with setTimeout function to defer retry execution. Default:

{ start: 500, end: 1000 }

maxRetryCount (Optional)

Maximum number of times request can be repeated Default: 3

Retry Exhaust

In case of all retries were exhausted, then last error received will be passed to done function.