JavaScript object to call authorised AWS functions and automatically retry failed calls multiple times

aws-request.js

"use strict";

//
// Class to call and retry AWS requests
//
var AwsRequest = (function () {

    //
    // Constructor
    //
    function AwsRequest(retryCount, retryDelay) {

        // Set some default values
        if (retryCount == null) {
            retryCount = this.DEFAULT_RETRY_COUNT();
        }
        if (retryDelay == null) {
            retryDelay = this.DEFAULT_RETRY_DELAY_MILLISECONDS();
        }

        // Save our retry counts
        this.retryCount = retryCount;
        this.retryDelay = retryDelay;
    }

    // Properties
    AwsRequest.prototype.DEFAULT_RETRY_COUNT = function () { return 3; };
    AwsRequest.prototype.DEFAULT_RETRY_DELAY_MILLISECONDS = function () { return 1000; };

    //
    // Requests a call to an AWS function
    //
    AwsRequest.prototype.request = function (params, service, functionRequest, completedCallback, successCallback, errorCallback) {
        // Kick off the request
        this.__runRequest(this, 0, params, service, functionRequest, completedCallback, successCallback, errorCallback);
    };

    //
    // Triggers the run request and runs it multiple times if needed
    //
    AwsRequest.prototype.__runRequest = function (self, callbackCount, params, service, functionRequest, completedCallback, successCallback, errorCallback) {

        // Bypass, and make our requests directly so
        service.makeRequest(functionRequest, params, function (error, data) {

            if (error) {
                // Call the error callback so we can display valid information before dumping the stack
                if (errorCallback !== null) {
                    var updatedParams = errorCallback(error, params);
                    if (updatedParams != null) {
                        params = updatedParams;
                    }
                }
                console.log(error, error.stack);

                // Do we need to try again?
                ++callbackCount;
                if (callbackCount < self.retryCount) {
                    // Try again after a given delay
                    setTimeout(function () {
                        self.__runRequest(self, callbackCount, params, service, functionRequest, completedCallback, successCallback, errorCallback);
                    }, self.retryDelay);

                } else {
                    // We failed, so send it back
                    completedCallback(error, null);
                }

            } else {
                // We're done, so send the data back
                if (successCallback !== null) {
                    successCallback(data);
                }
                completedCallback(null, data);
            }
        });
    };

    // Object creation
    return AwsRequest;
} ());

// Available exports
exports.AwsRequest = AwsRequest;