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var RetryOperation = require('./retry_operation');
exports.operation = function(options) {
var timeouts = exports.timeouts(options);
return new RetryOperation(timeouts, {
forever: options && options.forever,
unref: options && options.unref
});
};
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 * opts.minTimeout * 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() {
var op = exports.operation(options);
var args = Array.prototype.slice.call(arguments);
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);
});
};
obj[method].options = options;
}
};
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