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Diffstat (limited to 'node_modules/orchestrator/index.js')
-rw-r--r-- | node_modules/orchestrator/index.js | 304 |
1 files changed, 304 insertions, 0 deletions
diff --git a/node_modules/orchestrator/index.js b/node_modules/orchestrator/index.js new file mode 100644 index 000000000..b13d9927d --- /dev/null +++ b/node_modules/orchestrator/index.js @@ -0,0 +1,304 @@ +/*jshint node:true */ + +"use strict"; + +var util = require('util'); +var events = require('events'); +var EventEmitter = events.EventEmitter; +var runTask = require('./lib/runTask'); + +var Orchestrator = function () { + EventEmitter.call(this); + this.doneCallback = undefined; // call this when all tasks in the queue are done + this.seq = []; // the order to run the tasks + this.tasks = {}; // task objects: name, dep (list of names of dependencies), fn (the task to run) + this.isRunning = false; // is the orchestrator running tasks? .start() to start, .stop() to stop +}; +util.inherits(Orchestrator, EventEmitter); + + Orchestrator.prototype.reset = function () { + if (this.isRunning) { + this.stop(null); + } + this.tasks = {}; + this.seq = []; + this.isRunning = false; + this.doneCallback = undefined; + return this; + }; + Orchestrator.prototype.add = function (name, dep, fn) { + if (!fn && typeof dep === 'function') { + fn = dep; + dep = undefined; + } + dep = dep || []; + fn = fn || function () {}; // no-op + if (!name) { + throw new Error('Task requires a name'); + } + // validate name is a string, dep is an array of strings, and fn is a function + if (typeof name !== 'string') { + throw new Error('Task requires a name that is a string'); + } + if (typeof fn !== 'function') { + throw new Error('Task '+name+' requires a function that is a function'); + } + if (!Array.isArray(dep)) { + throw new Error('Task '+name+' can\'t support dependencies that is not an array of strings'); + } + dep.forEach(function (item) { + if (typeof item !== 'string') { + throw new Error('Task '+name+' dependency '+item+' is not a string'); + } + }); + this.tasks[name] = { + fn: fn, + dep: dep, + name: name + }; + return this; + }; + Orchestrator.prototype.task = function (name, dep, fn) { + if (dep || fn) { + // alias for add, return nothing rather than this + this.add(name, dep, fn); + } else { + return this.tasks[name]; + } + }; + Orchestrator.prototype.hasTask = function (name) { + return !!this.tasks[name]; + }; + // tasks and optionally a callback + Orchestrator.prototype.start = function() { + var args, arg, names = [], lastTask, i, seq = []; + args = Array.prototype.slice.call(arguments, 0); + if (args.length) { + lastTask = args[args.length-1]; + if (typeof lastTask === 'function') { + this.doneCallback = lastTask; + args.pop(); + } + for (i = 0; i < args.length; i++) { + arg = args[i]; + if (typeof arg === 'string') { + names.push(arg); + } else if (Array.isArray(arg)) { + names = names.concat(arg); // FRAGILE: ASSUME: it's an array of strings + } else { + throw new Error('pass strings or arrays of strings'); + } + } + } + if (this.isRunning) { + // reset specified tasks (and dependencies) as not run + this._resetSpecificTasks(names); + } else { + // reset all tasks as not run + this._resetAllTasks(); + } + if (this.isRunning) { + // if you call start() again while a previous run is still in play + // prepend the new tasks to the existing task queue + names = names.concat(this.seq); + } + if (names.length < 1) { + // run all tasks + for (i in this.tasks) { + if (this.tasks.hasOwnProperty(i)) { + names.push(this.tasks[i].name); + } + } + } + seq = []; + try { + this.sequence(this.tasks, names, seq, []); + } catch (err) { + // Is this a known error? + if (err) { + if (err.missingTask) { + this.emit('task_not_found', {message: err.message, task:err.missingTask, err: err}); + } + if (err.recursiveTasks) { + this.emit('task_recursion', {message: err.message, recursiveTasks:err.recursiveTasks, err: err}); + } + } + this.stop(err); + return this; + } + this.seq = seq; + this.emit('start', {message:'seq: '+this.seq.join(',')}); + if (!this.isRunning) { + this.isRunning = true; + } + this._runStep(); + return this; + }; + Orchestrator.prototype.stop = function (err, successfulFinish) { + this.isRunning = false; + if (err) { + this.emit('err', {message:'orchestration failed', err:err}); + } else if (successfulFinish) { + this.emit('stop', {message:'orchestration succeeded'}); + } else { + // ASSUME + err = 'orchestration aborted'; + this.emit('err', {message:'orchestration aborted', err: err}); + } + if (this.doneCallback) { + // Avoid calling it multiple times + this.doneCallback(err); + } else if (err && !this.listeners('err').length) { + // No one is listening for the error so speak louder + throw err; + } + }; + Orchestrator.prototype.sequence = require('sequencify'); + Orchestrator.prototype.allDone = function () { + var i, task, allDone = true; // nothing disputed it yet + for (i = 0; i < this.seq.length; i++) { + task = this.tasks[this.seq[i]]; + if (!task.done) { + allDone = false; + break; + } + } + return allDone; + }; + Orchestrator.prototype._resetTask = function(task) { + if (task) { + if (task.done) { + task.done = false; + } + delete task.start; + delete task.stop; + delete task.duration; + delete task.hrDuration; + delete task.args; + } + }; + Orchestrator.prototype._resetAllTasks = function() { + var task; + for (task in this.tasks) { + if (this.tasks.hasOwnProperty(task)) { + this._resetTask(this.tasks[task]); + } + } + }; + Orchestrator.prototype._resetSpecificTasks = function (names) { + var i, name, t; + + if (names && names.length) { + for (i = 0; i < names.length; i++) { + name = names[i]; + t = this.tasks[name]; + if (t) { + this._resetTask(t); + if (t.dep && t.dep.length) { + this._resetSpecificTasks(t.dep); // recurse + } + //} else { + // FRAGILE: ignore that the task doesn't exist + } + } + } + }; + Orchestrator.prototype._runStep = function () { + var i, task; + if (!this.isRunning) { + return; // user aborted, ASSUME: stop called previously + } + for (i = 0; i < this.seq.length; i++) { + task = this.tasks[this.seq[i]]; + if (!task.done && !task.running && this._readyToRunTask(task)) { + this._runTask(task); + } + if (!this.isRunning) { + return; // task failed or user aborted, ASSUME: stop called previously + } + } + if (this.allDone()) { + this.stop(null, true); + } + }; + Orchestrator.prototype._readyToRunTask = function (task) { + var ready = true, // no one disproved it yet + i, name, t; + if (task.dep.length) { + for (i = 0; i < task.dep.length; i++) { + name = task.dep[i]; + t = this.tasks[name]; + if (!t) { + // FRAGILE: this should never happen + this.stop("can't run "+task.name+" because it depends on "+name+" which doesn't exist"); + ready = false; + break; + } + if (!t.done) { + ready = false; + break; + } + } + } + return ready; + }; + Orchestrator.prototype._stopTask = function (task, meta) { + task.duration = meta.duration; + task.hrDuration = meta.hrDuration; + task.running = false; + task.done = true; + }; + Orchestrator.prototype._emitTaskDone = function (task, message, err) { + if (!task.args) { + task.args = {task:task.name}; + } + task.args.duration = task.duration; + task.args.hrDuration = task.hrDuration; + task.args.message = task.name+' '+message; + var evt = 'stop'; + if (err) { + task.args.err = err; + evt = 'err'; + } + // 'task_stop' or 'task_err' + this.emit('task_'+evt, task.args); + }; + Orchestrator.prototype._runTask = function (task) { + var that = this; + + task.args = {task:task.name, message:task.name+' started'}; + this.emit('task_start', task.args); + task.running = true; + + runTask(task.fn.bind(this), function (err, meta) { + that._stopTask.call(that, task, meta); + that._emitTaskDone.call(that, task, meta.runMethod, err); + if (err) { + return that.stop.call(that, err); + } + that._runStep.call(that); + }); + }; + +// FRAGILE: ASSUME: this list is an exhaustive list of events emitted +var events = ['start','stop','err','task_start','task_stop','task_err','task_not_found','task_recursion']; + +var listenToEvent = function (target, event, callback) { + target.on(event, function (e) { + e.src = event; + callback(e); + }); +}; + + Orchestrator.prototype.onAll = function (callback) { + var i; + if (typeof callback !== 'function') { + throw new Error('No callback specified'); + } + + for (i = 0; i < events.length; i++) { + listenToEvent(this, events[i], callback); + } + }; + +module.exports = Orchestrator; |