Neo's Playing Morpheus

    @artisnull/asyncquence

    0.1.0 • Public • Published

    asyncquence

    Run synchronous and asynchronous functions in sequence, with hooks, value pass through, and more!


    Key Features

    • Executes and resolves functions in FIFO sequence, asynchronously
    • You can add to the sequence whenever you want
    • Add an array of functions, and it will be added in order into the sequence
    • Emits lifecycle events such as START, PROGRESS, or ERROR
    • Pause/Resume or Cancel whenever you want
    • Pass the results of the previous task through to the next one

    Sample usage

    Basic:
    const asq = new Asyncquence()
    
    const func1 = () => Promise.resolve(1)
    const func2 = (x) => (x + 2)
    
    const results = asq.add([
      [func1],
      [func2, [0]]
    ])
    
    results[0].then(console.log) // 1
    results[1].then(console.log) // 2

    Add an array of tasks get an array of promises back in the order that we added the tasks. Pretty straightforward.

    With passthrough:
    const asq = new Asyncquence({
      passPrevValue: true
    })
    
    const func1 = () => Promise.resolve(4)
    const func2 = (x) => (x + 10)
    
    const results = asq.add([
      [func1],
      [func2]
    ])
    
    results[0].then(console.log) // 4
    results[1].then(console.log) // 14

    Table of Contents

    Reference

    API


    Reference

    config

    Defaults
    const DEFAULT_CONFIG = {
      execImmediate: true,
      cancelOnError: false,
      passPrevValue: false,
      silent: false
    }
    Description
    • execImmediate
      • true: when first Task is added, it will be executed
      • false: the start() method is called to begin execution
    • cancelOnError
      • true: an error during execution will stop the rest of the sequence from completing
      • false: an error during execution is reported via rejection and the error lifecycle event, but the sequence continues to the next Task
    • passPrevValue
      • true: the result of the last Task is passed as the last argument to the next Task
      • false: each Task is executed independently
    • silent
      • true: silences default event messages
      • false: default events are logged to console

    Events

    Not all events pass an argument to the event listener
    Format: EVENT_NAME: (argument)


    STATUS_CHANGE : ('READY'|'PAUSED'|'RUNNING'|'STOPPED')
    START
    PROGRESS :
    {
      remaining: numRemaining // int
      completed: numCompleted // int
      percentComplete: percentString //String
    }
    COMPLETE
    PAUSE : (nextTask)
    RESUME : (nextTask)
    CANCEL
    ERROR: (err)

    Task

    The format of function and arguments that asyncquence expects.
    Can be one of the following:

    const Task = [fn, [args]]
    // OR
    const Task = {
      method: fn,
      args: [args]
    }

    Adding single tasks is simpler: asq.add(fn, [args])



    API

    new Asyncquence(config)

    Returns new Asyncquence instance with the specified config

    const asq = new Asyncquence()

    add(Task) : Promise[]

    add([Task,[...Tasks]]) : Promise[]

    Adds a task(s) to the back of the queue to be executed. Returns an array of promises at indices corresponding to the index of each task added. See Task for reference.

    Triggers 'READY' status change when adding a task to an empty queue if config option execImmediate:false
    Triggers START Event when adding a task to an empty queue if config option execImmediate:true

    // Single task
    const res = asq.add(Task) // res[0] has Promise for this task
    
    // Multiple tasks
    const res = asq.add([Task1, Task2]) // res[0] for Task1, res[1] for Task2

    addEventListener(name:Event, callback:function)

    Registers a function to call when the specified event takes place. See Event for reference.

    asq.addEventListener('STATUS_CHANGE', cb)

    cancel()

    Stops execution of current Task and empties queue. Doesn't affect event listeners

    Triggers CANCEL Event
    Triggers 'STOPPED' status change

    asq.cancel()

    clear()

    Immediately empties queue and removes all event listeners, dangerous
    Use cancel() to safely stop an asyncquence

    Won't trigger any event listeners, as they are removed

    asq.clear()

    clearEventListeners()

    Immediately removes all event listeners

    asq.clearEventListeners()

    pause()

    Pauses execution of sequence. Any currently running Tasks will complete, but no future Tasks will be executed until resume() is called

    Triggers 'PAUSED' status change

    asq.pause()

    removeEventListener(name:Event, callback:function)

    Removes the specified event listener

    asq.removeEventListener('STATUS_CHANGE', cb)

    resume()

    Resumes sequence execution from a paused state.

    Triggers 'RESUME' status change

    asq.resume()

    start()

    Begins execution of the first element in the sequence. Not applicable if config option: execImmediate:true, as execution begins automatically

    Triggers START Event
    Triggers 'RUNNING' status change

    asq.start()

    LICENSE

    MIT License

    Copyright (c) 2018 artisnull

    Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

    Install

    npm i @artisnull/asyncquence

    DownloadsWeekly Downloads

    1

    Version

    0.1.0

    License

    MIT

    Last publish

    Collaborators

    • artisnull