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diff --git a/v3/auto.js.html b/v3/auto.js.html new file mode 100644 index 0000000..e4239a8 --- /dev/null +++ b/v3/auto.js.html @@ -0,0 +1,364 @@ +<!DOCTYPE html> +<html lang="en"> +<head> + + <meta charset="utf-8"> + <meta name="viewport" content="width=device-width, initial-scale=1"> + <title>auto.js - Documentation</title> + + + <link rel="icon" href="favicon.ico?v=2"> + <link rel="stylesheet" href="https://cdn.jsdelivr.net/bootstrap/3.3.6/css/bootstrap.min.css"> + + <link rel="stylesheet" href="styles/prettify-tomorrow.css"> + + <link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Montserrat:400,700"> + <link rel="stylesheet" href="styles/jsdoc-default.css"> + + <!--[if lt IE 9]> + <script src="//html5shiv.googlecode.com/svn/trunk/html5.js"></script> + <![endif]--> + <link type="text/css" rel="stylesheet" href="https://cdn.jsdelivr.net/ionicons/2.0.1/css/ionicons.min.css"> +</head> +<body> + +<div class="navbar navbar-default navbar-fixed-top"> + <div class="navbar-header"> + <a class="navbar-brand" href="../"> + <img src="img/async-logo.svg" alt="Async.js"> + </a> + </div> + <ul class="nav navbar-nav"> + <li id="version-dropdown" class="dropdown"> + <a href="#" class="dropdown-toggle vertically-centered" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">v3.0.1 <span class="caret"></span> + </a> + <ul class="dropdown-menu"> + <li><a href="../v3/">v3.0.x</a></li> + <li><a href="../v2/">v2.6.2</a></li> + <li> + <a href="https://github.com/caolan/async/blob/v1.5.2/README.md">v1.5.x</a> + </li> + </ul> + </li> + <li><a href="./index.html">Home</a></li> + <li><a href="./docs.html">Docs</a></li> + <li><a href="https://github.com/caolan/async/blob/master/CHANGELOG.md">Changelog</a></li> + <li><a href="https://github.com/caolan/async"><i class="ion-social-github" aria-hidden="true"></i></a></li> + </ul> + <ul class="nav navbar-nav navbar-right"> + <form class="navbar-form navbar-left" role="search"> + <div class="form-group"> + <input type="text" class="form-control typeahead" id="doc-search" placeholder="Search" autofocus> + </div> + </form> + </ul> +</div> + + +<input type="checkbox" id="nav-trigger" class="nav-trigger"> +<label for="nav-trigger" class="navicon-button x"> + <div class="navicon"></div> +</label> + +<label for="nav-trigger" class="overlay"></label> + +<div id="main"> + <div id="main-container" data-spy="scroll" data-target="#toc" data-offset="50"> + + <h1 class="page-title">auto.js</h1> + + + + + + + + <section> + <article> + <pre class="prettyprint source linenums"><code>import once from './internal/once'; +import onlyOnce from './internal/onlyOnce'; +import wrapAsync from './internal/wrapAsync'; +import { promiseCallback, PROMISE_SYMBOL } from './internal/promiseCallback' + +/** + * Determines the best order for running the {@link AsyncFunction}s in `tasks`, based on + * their requirements. Each function can optionally depend on other functions + * being completed first, and each function is run as soon as its requirements + * are satisfied. + * + * If any of the {@link AsyncFunction}s pass an error to their callback, the `auto` sequence + * will stop. Further tasks will not execute (so any other functions depending + * on it will not run), and the main `callback` is immediately called with the + * error. + * + * {@link AsyncFunction}s also receive an object containing the results of functions which + * have completed so far as the first argument, if they have dependencies. If a + * task function has no dependencies, it will only be passed a callback. + * + * @name auto + * @static + * @memberOf module:ControlFlow + * @method + * @category Control Flow + * @param {Object} tasks - An object. Each of its properties is either a + * function or an array of requirements, with the {@link AsyncFunction} itself the last item + * in the array. The object's key of a property serves as the name of the task + * defined by that property, i.e. can be used when specifying requirements for + * other tasks. The function receives one or two arguments: + * * a `results` object, containing the results of the previously executed + * functions, only passed if the task has any dependencies, + * * a `callback(err, result)` function, which must be called when finished, + * passing an `error` (which can be `null`) and the result of the function's + * execution. + * @param {number} [concurrency=Infinity] - An optional `integer` for + * determining the maximum number of tasks that can be run in parallel. By + * default, as many as possible. + * @param {Function} [callback] - An optional callback which is called when all + * the tasks have been completed. It receives the `err` argument if any `tasks` + * pass an error to their callback. Results are always returned; however, if an + * error occurs, no further `tasks` will be performed, and the results object + * will only contain partial results. Invoked with (err, results). + * @returns {Promise} a promise, if a callback is not passed + * @example + * + * async.auto({ + * // this function will just be passed a callback + * readData: async.apply(fs.readFile, 'data.txt', 'utf-8'), + * showData: ['readData', function(results, cb) { + * // results.readData is the file's contents + * // ... + * }] + * }, callback); + * + * async.auto({ + * get_data: function(callback) { + * console.log('in get_data'); + * // async code to get some data + * callback(null, 'data', 'converted to array'); + * }, + * make_folder: function(callback) { + * console.log('in make_folder'); + * // async code to create a directory to store a file in + * // this is run at the same time as getting the data + * callback(null, 'folder'); + * }, + * write_file: ['get_data', 'make_folder', function(results, callback) { + * console.log('in write_file', JSON.stringify(results)); + * // once there is some data and the directory exists, + * // write the data to a file in the directory + * callback(null, 'filename'); + * }], + * email_link: ['write_file', function(results, callback) { + * console.log('in email_link', JSON.stringify(results)); + * // once the file is written let's email a link to it... + * // results.write_file contains the filename returned by write_file. + * callback(null, {'file':results.write_file, 'email':'user@example.com'}); + * }] + * }, function(err, results) { + * console.log('err = ', err); + * console.log('results = ', results); + * }); + */ +export default function auto(tasks, concurrency, callback) { + if (typeof concurrency !== 'number') { + // concurrency is optional, shift the args. + callback = concurrency; + concurrency = null; + } + callback = once(callback || promiseCallback()); + var numTasks = Object.keys(tasks).length; + if (!numTasks) { + return callback(null); + } + if (!concurrency) { + concurrency = numTasks; + } + + var results = {}; + var runningTasks = 0; + var canceled = false; + var hasError = false; + + var listeners = Object.create(null); + + var readyTasks = []; + + // for cycle detection: + var readyToCheck = []; // tasks that have been identified as reachable + // without the possibility of returning to an ancestor task + var uncheckedDependencies = {}; + + Object.keys(tasks).forEach(key => { + var task = tasks[key] + if (!Array.isArray(task)) { + // no dependencies + enqueueTask(key, [task]); + readyToCheck.push(key); + return; + } + + var dependencies = task.slice(0, task.length - 1); + var remainingDependencies = dependencies.length; + if (remainingDependencies === 0) { + enqueueTask(key, task); + readyToCheck.push(key); + return; + } + uncheckedDependencies[key] = remainingDependencies; + + dependencies.forEach(dependencyName => { + if (!tasks[dependencyName]) { + throw new Error('async.auto task `' + key + + '` has a non-existent dependency `' + + dependencyName + '` in ' + + dependencies.join(', ')); + } + addListener(dependencyName, () => { + remainingDependencies--; + if (remainingDependencies === 0) { + enqueueTask(key, task); + } + }); + }); + }); + + checkForDeadlocks(); + processQueue(); + + function enqueueTask(key, task) { + readyTasks.push(() => runTask(key, task)); + } + + function processQueue() { + if (canceled) return + if (readyTasks.length === 0 && runningTasks === 0) { + return callback(null, results); + } + while(readyTasks.length && runningTasks < concurrency) { + var run = readyTasks.shift(); + run(); + } + + } + + function addListener(taskName, fn) { + var taskListeners = listeners[taskName]; + if (!taskListeners) { + taskListeners = listeners[taskName] = []; + } + + taskListeners.push(fn); + } + + function taskComplete(taskName) { + var taskListeners = listeners[taskName] || []; + taskListeners.forEach(fn => fn()); + processQueue(); + } + + + function runTask(key, task) { + if (hasError) return; + + var taskCallback = onlyOnce((err, ...result) => { + runningTasks--; + if (err === false) { + canceled = true + return + } + if (result.length < 2) { + [result] = result; + } + if (err) { + var safeResults = {}; + Object.keys(results).forEach(rkey => { + safeResults[rkey] = results[rkey]; + }); + safeResults[key] = result; + hasError = true; + listeners = Object.create(null); + if (canceled) return + callback(err, safeResults); + } else { + results[key] = result; + taskComplete(key); + } + }); + + runningTasks++; + var taskFn = wrapAsync(task[task.length - 1]); + if (task.length > 1) { + taskFn(results, taskCallback); + } else { + taskFn(taskCallback); + } + } + + function checkForDeadlocks() { + // Kahn's algorithm + // https://en.wikipedia.org/wiki/Topological_sorting#Kahn.27s_algorithm + // http://connalle.blogspot.com/2013/10/topological-sortingkahn-algorithm.html + var currentTask; + var counter = 0; + while (readyToCheck.length) { + currentTask = readyToCheck.pop(); + counter++; + getDependents(currentTask).forEach(dependent => { + if (--uncheckedDependencies[dependent] === 0) { + readyToCheck.push(dependent); + } + }); + } + + if (counter !== numTasks) { + throw new Error( + 'async.auto cannot execute tasks due to a recursive dependency' + ); + } + } + + function getDependents(taskName) { + var result = []; + Object.keys(tasks).forEach(key => { + const task = tasks[key] + if (Array.isArray(task) && task.indexOf(taskName) >= 0) { + result.push(key); + } + }); + return result; + } + + return callback[PROMISE_SYMBOL] +} +</code></pre> + </article> + </section> + + + + + <footer> + Documentation generated by <a href="https://github.com/jsdoc3/jsdoc">JSDoc 3.5.5</a> using the Minami theme. +</footer></div> +</div> + +<nav id="toc"> + <h3>Methods:</h3><ul class="nav methods"><li class="toc-header"><a href="docs.html#collections">Collections</a></li><li data-type="method" class="toc-method"><a href="docs.html#concat">concat</a></li><li data-type="method" class="toc-method"><a href="docs.html#concatLimit">concatLimit</a></li><li data-type="method" class="toc-method"><a href="docs.html#concatSeries">concatSeries</a></li><li data-type="method" class="toc-method"><a href="docs.html#detect">detect</a></li><li data-type="method" class="toc-method"><a href="docs.html#detectLimit">detectLimit</a></li><li data-type="method" class="toc-method"><a href="docs.html#detectSeries">detectSeries</a></li><li data-type="method" class="toc-method"><a href="docs.html#each">each</a></li><li data-type="method" class="toc-method"><a href="docs.html#eachLimit">eachLimit</a></li><li data-type="method" class="toc-method"><a href="docs.html#eachOf">eachOf</a></li><li data-type="method" class="toc-method"><a href="docs.html#eachOfLimit">eachOfLimit</a></li><li data-type="method" class="toc-method"><a href="docs.html#eachOfSeries">eachOfSeries</a></li><li data-type="method" class="toc-method"><a href="docs.html#eachSeries">eachSeries</a></li><li data-type="method" class="toc-method"><a href="docs.html#every">every</a></li><li data-type="method" class="toc-method"><a href="docs.html#everyLimit">everyLimit</a></li><li data-type="method" class="toc-method"><a href="docs.html#everySeries">everySeries</a></li><li data-type="method" class="toc-method"><a href="docs.html#filter">filter</a></li><li data-type="method" class="toc-method"><a href="docs.html#filterLimit">filterLimit</a></li><li data-type="method" class="toc-method"><a href="docs.html#filterSeries">filterSeries</a></li><li data-type="method" class="toc-method"><a href="docs.html#groupBy">groupBy</a></li><li data-type="method" class="toc-method"><a href="docs.html#groupByLimit">groupByLimit</a></li><li data-type="method" class="toc-method"><a href="docs.html#groupBySeries">groupBySeries</a></li><li data-type="method" class="toc-method"><a href="docs.html#map">map</a></li><li data-type="method" class="toc-method"><a href="docs.html#mapLimit">mapLimit</a></li><li data-type="method" class="toc-method"><a href="docs.html#mapSeries">mapSeries</a></li><li data-type="method" class="toc-method"><a href="docs.html#mapValues">mapValues</a></li><li data-type="method" class="toc-method"><a href="docs.html#mapValuesLimit">mapValuesLimit</a></li><li data-type="method" class="toc-method"><a href="docs.html#mapValuesSeries">mapValuesSeries</a></li><li data-type="method" class="toc-method"><a href="docs.html#reduce">reduce</a></li><li data-type="method" class="toc-method"><a href="docs.html#reduceRight">reduceRight</a></li><li data-type="method" class="toc-method"><a href="docs.html#reject">reject</a></li><li data-type="method" class="toc-method"><a href="docs.html#rejectLimit">rejectLimit</a></li><li data-type="method" class="toc-method"><a href="docs.html#rejectSeries">rejectSeries</a></li><li data-type="method" class="toc-method"><a href="docs.html#some">some</a></li><li data-type="method" class="toc-method"><a href="docs.html#someLimit">someLimit</a></li><li data-type="method" class="toc-method"><a href="docs.html#someSeries">someSeries</a></li><li data-type="method" class="toc-method"><a href="docs.html#sortBy">sortBy</a></li><li data-type="method" class="toc-method"><a href="docs.html#transform">transform</a></li><li class="toc-header"><a href="docs.html#controlflow">Control Flow</a></li><li data-type="method" class="toc-method"><a href="docs.html#applyEach">applyEach</a></li><li data-type="method" class="toc-method"><a href="docs.html#applyEachSeries">applyEachSeries</a></li><li data-type="method" class="toc-method active"><a href="docs.html#auto">auto</a></li><li data-type="method" class="toc-method"><a href="docs.html#autoInject">autoInject</a></li><li data-type="method" class="toc-method"><a href="docs.html#cargo">cargo</a></li><li data-type="method" class="toc-method"><a href="docs.html#cargoQueue">cargoQueue</a></li><li data-type="method" class="toc-method"><a href="docs.html#compose">compose</a></li><li data-type="method" class="toc-method"><a href="docs.html#doUntil">doUntil</a></li><li data-type="method" class="toc-method"><a href="docs.html#doWhilst">doWhilst</a></li><li data-type="method" class="toc-method"><a href="docs.html#forever">forever</a></li><li data-type="method" class="toc-method"><a href="docs.html#parallel">parallel</a></li><li data-type="method" class="toc-method"><a href="docs.html#parallelLimit">parallelLimit</a></li><li data-type="method" class="toc-method"><a href="docs.html#priorityQueue">priorityQueue</a></li><li data-type="method" class="toc-method"><a href="docs.html#queue">queue</a></li><li data-type="method" class="toc-method"><a href="docs.html#race">race</a></li><li data-type="method" class="toc-method"><a href="docs.html#retry">retry</a></li><li data-type="method" class="toc-method"><a href="docs.html#retryable">retryable</a></li><li data-type="method" class="toc-method"><a href="docs.html#seq">seq</a></li><li data-type="method" class="toc-method"><a href="docs.html#series">series</a></li><li data-type="method" class="toc-method"><a href="docs.html#times">times</a></li><li data-type="method" class="toc-method"><a href="docs.html#timesLimit">timesLimit</a></li><li data-type="method" class="toc-method"><a href="docs.html#timesSeries">timesSeries</a></li><li data-type="method" class="toc-method"><a href="docs.html#tryEach">tryEach</a></li><li data-type="method" class="toc-method"><a href="docs.html#until">until</a></li><li data-type="method" class="toc-method"><a href="docs.html#waterfall">waterfall</a></li><li data-type="method" class="toc-method"><a href="docs.html#whilst">whilst</a></li><li class="toc-header"><a href="docs.html#utils">Utils</a></li><li data-type="method" class="toc-method"><a href="docs.html#apply">apply</a></li><li data-type="method" class="toc-method"><a href="docs.html#asyncify">asyncify</a></li><li data-type="method" class="toc-method"><a href="docs.html#constant">constant</a></li><li data-type="method" class="toc-method"><a href="docs.html#dir">dir</a></li><li data-type="method" class="toc-method"><a href="docs.html#ensureAsync">ensureAsync</a></li><li data-type="method" class="toc-method"><a href="docs.html#log">log</a></li><li data-type="method" class="toc-method"><a href="docs.html#memoize">memoize</a></li><li data-type="method" class="toc-method"><a href="docs.html#nextTick">nextTick</a></li><li data-type="method" class="toc-method"><a href="docs.html#reflect">reflect</a></li><li data-type="method" class="toc-method"><a href="docs.html#reflectAll">reflectAll</a></li><li data-type="method" class="toc-method"><a href="docs.html#setImmediate">setImmediate</a></li><li data-type="method" class="toc-method"><a href="docs.html#timeout">timeout</a></li><li data-type="method" class="toc-method"><a href="docs.html#unmemoize">unmemoize</a></li></ul><h3>Methods:</h3> +</nav> + +<br class="clear"> + + + + +<script src="https://cdn.jsdelivr.net/prettify/0.1/prettify.js"></script> + +<script src="https://cdn.jsdelivr.net/jquery/2.2.4/jquery.min.js"></script> +<script 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