var RetryOperation = require('./retry_operation'); exports.operation = function(options) { var timeouts = exports.timeouts(options); return new RetryOperation(timeouts, { forever: options && (options.forever || options.retries === Infinity), unref: options && options.unref, maxRetryTime: options && options.maxRetryTime }); }; exports.timeouts = function(options) { if (options instanceof Array) { return [].concat(options); } var opts = { retries: 10, factor: 2, minTimeout: 1 * 1000, maxTimeout: Infinity, randomize: false }; for (var key in options) { opts[key] = options[key]; } if (opts.minTimeout > opts.maxTimeout) { throw new Error('minTimeout is greater than maxTimeout'); } var timeouts = []; for (var i = 0; i < opts.retries; i++) { timeouts.push(this.createTimeout(i, opts)); } if (options && options.forever && !timeouts.length) { timeouts.push(this.createTimeout(i, opts)); } // sort the array numerically ascending timeouts.sort(function(a,b) { return a - b; }); return timeouts; }; exports.createTimeout = function(attempt, opts) { var random = (opts.randomize) ? (Math.random() + 1) : 1; var timeout = Math.round(random * Math.max(opts.minTimeout, 1) * Math.pow(opts.factor, attempt)); timeout = Math.min(timeout, opts.maxTimeout); return timeout; }; exports.wrap = function(obj, options, methods) { if (options instanceof Array) { methods = options; options = null; } if (!methods) { methods = []; for (var key in obj) { if (typeof obj[key] === 'function') { methods.push(key); } } } for (var i = 0; i < methods.length; i++) { var method = methods[i]; var original = obj[method]; obj[method] = function retryWrapper(original) { var op = exports.operation(options); var args = Array.prototype.slice.call(arguments, 1); var callback = args.pop(); args.push(function(err) { if (op.retry(err)) { return; } if (err) { arguments[0] = op.mainError(); } callback.apply(this, arguments); }); op.attempt(function() { original.apply(obj, args); }); }.bind(obj, original); obj[method].options = options; } };