import config from "config"; class DeferredPromise { // eslint-disable-next-line require-jsdoc constructor() { this.promise = new Promise((resolve, reject) => { this.reject = reject; this.resolve = resolve; }); } } class QueueTask { // eslint-disable-next-line require-jsdoc constructor(job, options, priority) { this.job = job; this.options = options; this.priority = priority; this.job.setTask(this); } } class Queue { // eslint-disable-next-line require-jsdoc constructor(handleTaskFunction, concurrency) { this.handleTaskFunction = handleTaskFunction; this.concurrency = concurrency; this.queue = []; this.runningTasks = []; this.pausedTasks = []; this.paused = false; } /** * Pauses the queue, meaning no new jobs can be started. Jobs can still be added to the queue, and already running tasks won't be paused. */ pause() { this.paused = true; } /** * Resumes the queue. */ resume() { this.paused = false; setTimeout(() => { this._handleQueue(); }, 0); } /** * Returns the amount of jobs in the queue. * * @returns {number} - amount of jobs in queue */ lengthQueue() { return this.queue.length; } /** * Returns the amount of running jobs. * * @returns {number} - amount of running jobs */ lengthRunning() { return this.runningTasks.length; } /** * Returns the amount of running jobs. * * @returns {number} - amount of running jobs */ lengthPaused() { return this.pausedTasks.length; } /** * Adds a job to the queue, with a given priority. * * @param {object} job - the job that is to be added * @param {object} options - custom options e.g. isQuiet. Optional. * @param {number} priority - the priority of the to be added job */ push(job, options, priority) { this.queue.push(new QueueTask(job, options, priority)); setTimeout(() => { this._handleQueue(); }, 0); } /** * Removes a job currently running from the queue. * * @param {object} job - the job to be removed */ removeRunningJob(job) { this.runningTasks.remove(this.runningTasks.find(task => task.job.toString() === job.toString())); } /** * Pauses a job currently running from the queue. * * @param {object} job - the job to be pauses */ pauseRunningJob(job) { const task = this.runningTasks.find(task => task.job.toString() === job.toString()); if (!task) { console.log( `Attempted to pause job ${job.name} (${job.toString()}), but couldn't find it in running tasks.` ); return; } this.runningTasks.remove(task); this.pausedTasks.push(task); } /** * Resumes a job currently paused, adding the job back to the front of the queue * * @param {object} job - the job to be pauses */ resumeRunningJob(job) { const task = this.pausedTasks.find(task => task.job.toString() === job.toString()); if (!task) { console.log( `Attempted to resume job ${job.name} (${job.toString()}), but couldn't find it in paused tasks.` ); return; } this.pausedTasks.remove(task); this.queue.unshift(task); setTimeout(() => { this._handleQueue(); }, 0); } /** * Check if there's room for a job to be processed, and if there is, run it. */ _handleQueue() { if (this.queue.length > 0) { const task = this.queue.reduce((a, b) => (a.priority < b.priority ? a : b)); if (task) { if ((!this.paused && this.runningTasks.length < this.concurrency) || task.priority === -1) { this.queue.remove(task); this.runningTasks.push(task); this._handleTask(task); setTimeout(() => { this._handleQueue(); }, 0); } } } } /** * Handles a task, calling the handleTaskFunction provided in the constructor * * @param {object} task - the task to be handled */ _handleTask(task) { this.handleTaskFunction(task.job, task.options).finally(() => { this.runningTasks.remove(task); this._handleQueue(); }); } } class Job { // eslint-disable-next-line require-jsdoc constructor(name, payload, onFinish, module, parentJob) { this.name = name; this.payload = payload; this.response = null; this.responseType = null; this.onFinish = onFinish; this.module = module; this.parentJob = parentJob; this.childJobs = []; /* eslint-disable no-bitwise, eqeqeq */ this.uniqueId = "xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx".replace(/[xy]/g, c => { const r = (Math.random() * 16) | 0; const v = c == "x" ? r : (r & 0x3) | 0x8; return v.toString(16); }); this.status = "INITIALIZED"; this.task = null; } /** * Adds a child job to this job * * @param {object} childJob - the child job */ addChildJob(childJob) { this.childJobs.push(childJob); } /** * Sets the job status * * @param {string} status - the new status */ setStatus(status) { this.status = status; } /** * Sets the task for a job * * @param {string} task - the job task */ setTask(task) { this.task = task; } /** * Returns the UUID of the job, allowing you to compare jobs with toString * * @returns {string} - the job's UUID/uniqueId */ toString() { return this.uniqueId; } /** * Sets the response that will be provided to the onFinish DeferredPromise resolve/reject function, as soon as the job is done if it has no parent, or when the parent job is resumed * * @param {object} response - the response */ setResponse(response) { this.response = response; } /** * Sets the response type that is paired with the response. If it is RESOLVE/REJECT, then it will resolve/reject with the response. If it is RESOLVED/REJECTED, then it has already resolved/rejected with the response. * * @param {string} responseType - the response type, so RESOLVE/REJECT/RESOLVED/REJECTED */ setResponseType(responseType) { this.responseType = responseType; } /** * Removes child jobs to prevent memory leak */ cleanup() { this.childJobs = this.childJobs.map(() => null); } /** * Logs to the module of the job * * @param {any} args - Anything to be added to the log e.g. log type, log message */ log(...args) { args.splice(1, 0, this.name); // Adds the name of the job as the first argument (after INFO/SUCCESS/ERROR). this.module.log(...args); } } class MovingAverageCalculator { // eslint-disable-next-line require-jsdoc constructor() { this.count = 0; this._mean = 0; } /** * Updates the mean average * * @param {number} newValue - the new time it took to complete a job */ update(newValue) { this.count += 1; const differential = (newValue - this._mean) / this.count; this._mean += differential; } /** * Returns the mean average * * @returns {number} - returns the mean average */ get mean() { this.validate(); return this._mean; } /** * Checks that the mean is valid */ validate() { if (this.count === 0) throw new Error("Mean is undefined"); } } export default class CoreClass { /** * * @param {string} name - the name of the class * @param {object} options - optional options * @param {number} options.concurrency - how many jobs can run at the same time * @param {object} options.priorities - custom priorities for jobs */ constructor(name, options) { this.name = name; this.status = "UNINITIALIZED"; this.concurrency = options && options.concurrency ? options.concurrency : 10; this.jobQueue = new Queue((job, options) => this._runJob(job, options), this.concurrency); this.jobQueue.pause(); this.priorities = options && options.priorities ? options.priorities : {}; this.stage = 0; this.jobStatistics = {}; this.logRules = config.get("customLoggingPerModule")[name] ? config.get("customLoggingPerModule")[name] : config.get("defaultLogging"); this.registerJobs(); } /** * Sets the status of a module * * @param {string} status - the new status of a module */ setStatus(status) { this.status = status; this.log("INFO", `Status changed to: ${status}`); if (this.status === "READY") this.jobQueue.resume(); else if (this.status === "FAIL" || this.status === "LOCKDOWN") this.jobQueue.pause(); } /** * Returns the status of a module * * @returns {string} - the status of a module */ getStatus() { return this.status; } /** * Changes the current stage of a module * * @param {string} stage - the new stage of a module */ setStage(stage) { this.stage = stage; } /** * Returns the current stage of a module * * @returns {string} - the current stage of a module */ getStage() { return this.stage; } /** * Initialises a module and handles initialise successes and failures */ _initialize() { this.setStatus("INITIALIZING"); this.initialize() .then(() => { this.setStatus("READY"); this.moduleManager.onInitialize(this); }) .catch(err => { console.error(err); this.setStatus("FAILED"); this.moduleManager.onFail(this); }); } /** * Creates a new log message * * @param {...any} args - anything to be included in the log message, the first argument is the type of log */ log(...args) { const _arguments = Array.from(args); const type = _arguments[0]; if (config.debug && config.debug.stationIssue === true && type === "STATION_ISSUE") { this.moduleManager.debugLogs.stationIssue.push(_arguments); return; } if (this.logRules.hideType.indexOf(type) !== -1) return; _arguments.splice(0, 1); const start = `|${this.name.toUpperCase()}|`; const numberOfSpacesNeeded = 20 - start.length; _arguments.unshift(`${start}${Array(numberOfSpacesNeeded).join(" ")}`); if (this.logRules.blacklistedTerms.some(blacklistedTerm => _arguments.join().indexOf(blacklistedTerm) !== -1)) return; if (type === "INFO" || type === "SUCCESS") { _arguments[0] += "\x1b[36m"; _arguments.push("\x1b[0m"); console.log.apply(null, _arguments); } else if (type === "ERROR") { _arguments[0] += "\x1b[31m"; _arguments.push("\x1b[0m"); console.error.apply(null, _arguments); } } /** * Sets up each job with the statistics service (includes mean average for job completion) */ registerJobs() { let props = []; let obj = this; do { props = props.concat(Object.getOwnPropertyNames(obj)); // eslint-disable-next-line no-cond-assign } while ((obj = Object.getPrototypeOf(obj))); const jobNames = props.sort().filter(prop => typeof this[prop] === "function" && prop === prop.toUpperCase()); jobNames.forEach(jobName => { this.jobStatistics[jobName] = { successful: 0, failed: 0, total: 0, averageTiming: new MovingAverageCalculator() }; }); } /** * Runs a job * * @param {string} name - the name of the job e.g. GET_PLAYLIST * @param {object} payload - any expected payload for the job itself * @param {object} parentJob - the parent job, if any * @param {number} priority - custom priority. Optional. * @param {object} options - custom options e.g. isQuiet. Optional. * @returns {Promise} - returns a promise */ runJob(name, payload, parentJob, priority, options) { /** Allows for any combination of optional parameters (parentJob, priority, options) */ let _options; let _priority; let _parentJob; if (parentJob) { if (typeof parentJob === "object") if (!parentJob.name) _options = parentJob; else _parentJob = parentJob; else if (typeof parentJob === "number") _priority = parentJob; } if (options) { if (typeof options === "object") if (options.name) _parentJob = options; else _options = options; if (typeof options === "number") _priority = options; } if (priority && typeof priority === "object") { if (!priority.name) _options = priority; else _parentJob = priority; } else _priority = priority; if (!_options) _options = { isQuiet: false }; const deferredPromise = new DeferredPromise(); const job = new Job(name, payload, deferredPromise, this, _parentJob); this.log("INFO", `Queuing job ${name} (${job.toString()})`); if (_parentJob) { _parentJob.addChildJob(job); if (_parentJob.status === "RUNNING") { this.log( "INFO", `Pausing job ${_parentJob.name} (${_parentJob.toString()}) since a child job has to run first` ); _parentJob.setStatus("WAITING_ON_CHILD_JOB"); _parentJob.module.jobQueue.pauseRunningJob(_parentJob); } else { this.log( "INFO", `Not pausing job ${_parentJob.name} (${_parentJob.toString()}) since it's already paused` ); } } job.setStatus("QUEUED"); let calculatedPriority = null; if (_priority) calculatedPriority = _priority; else if (this.priorities[name]) calculatedPriority = this.priorities[name]; else if (_parentJob) calculatedPriority = _parentJob.task.priority; else calculatedPriority = 10; this.jobQueue.push(job, _options, calculatedPriority); if ( config.debug && config.debug.stationIssue === true && config.debug.captureJobs && config.debug.captureJobs.indexOf(name) !== -1 ) { this.moduleManager.debugJobs.all.push({ job, _priority }); } return deferredPromise.promise; } /** * UNKNOWN * * @param {object} moduleManager - UNKNOWN */ setModuleManager(moduleManager) { this.moduleManager = moduleManager; } /** * Actually runs the job? UNKNOWN * * @param {object} job - object containing details of the job * @param {string} job.name - the name of the job e.g. GET_PLAYLIST * @param {string} job.payload - any expected payload for the job itself * @param {Promise} job.onFinish - deferred promise when the job is complete * @param {object} options - custom options e.g. isQuiet. Optional. * @returns {Promise} - returns a promise */ _runJob(job, options) { if (!options.isQuiet) this.log("INFO", `Running job ${job.name} (${job.toString()})`); return new Promise(resolve => { const startTime = Date.now(); const previousStatus = job.status; job.setStatus("RUNNING"); this.moduleManager.jobManager.addJob(job); if (previousStatus === "QUEUED") { if (!options.isQuiet) this.log("INFO", `Job ${job.name} (${job.toString()}) is queued, so calling it`); this[job.name] .apply(job, [job.payload]) .then(response => { if (!options.isQuiet) this.log("INFO", `Ran job ${job.name} (${job.toString()}) successfully`); job.setStatus("FINISHED"); job.setResponse(response); this.jobStatistics[job.name].successful += 1; job.setResponseType("RESOLVE"); if ( config.debug && config.debug.stationIssue === true && config.debug.captureJobs && config.debug.captureJobs.indexOf(job.name) !== -1 ) { this.moduleManager.debugJobs.completed.push({ status: "success", job, priority: job.task.priority, response }); } }) .catch(error => { this.log("INFO", `Running job ${job.name} (${job.toString()}) failed`); job.setStatus("FINISHED"); job.setResponse(error); job.setResponseType("REJECT"); this.jobStatistics[job.name].failed += 1; if ( config.debug && config.debug.stationIssue === true && config.debug.captureJobs && config.debug.captureJobs.indexOf(job.name) !== -1 ) { this.moduleManager.debugJobs.completed.push({ status: "error", job, error }); } }) .finally(() => { const endTime = Date.now(); const executionTime = endTime - startTime; this.jobStatistics[job.name].total += 1; this.jobStatistics[job.name].averageTiming.update(executionTime); this.moduleManager.jobManager.removeJob(job); job.cleanup(); if (!job.parentJob) { if (job.responseType === "RESOLVE") { job.onFinish.resolve(job.response); job.responseType = "RESOLVED"; } else if (job.responseType === "REJECT") { job.onFinish.reject(job.response); job.responseType = "REJECTED"; } } else if ( job.parentJob && job.parentJob.childJobs.find(childJob => childJob ? childJob.status !== "FINISHED" : true ) === undefined ) { if (job.parentJob.status !== "WAITING_ON_CHILD_JOB") { this.log( "ERROR", `Job ${ job.parentJob.name } (${job.parentJob.toString()}) had a child job complete even though it is not waiting on a child job. This should never happen.` ); } else { job.parentJob.setStatus("REQUEUED"); job.parentJob.module.jobQueue.resumeRunningJob(job.parentJob); } } resolve(); }); } else { this.log( "INFO", `Job ${job.name} (${job.toString()}) is re-queued, so resolving/rejecting all child jobs.` ); job.childJobs.forEach(childJob => { if (childJob.responseType === "RESOLVE") { childJob.onFinish.resolve(childJob.response); childJob.responseType = "RESOLVED"; } else if (childJob.responseType === "REJECT") { childJob.onFinish.reject(childJob.response); childJob.responseType = "REJECTED"; } }); } }); } }