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    rxjs-toolbox
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    2.2.2 • Public • Published

    RxJS-toolbox - set of custom operators and handy factory functions for RxJS

    Installation

    Install using NPM CLI

    npm install --save rxjs-toolbox
    

    forkJoin-transparent

    A combination operator that combines multiple sources and returns their last emitted data as well as percentage of their completion.

    Usage

    forkJoinWithProgress

    import { ajax } from 'rxjs/ajax';
    import { merge } from 'rxjs';
    `import { forkJoinWithProgress } from 'rxjs-toolbox';`
    import {tap, mergeMap, ignoreElements} from 'rxjs/operators';
     
    const getUserDetails = userIdsList => {
      
      const arrayOfObservables = userIdsList.map(userId =>
        ajax('https://jsonplaceholder.typicode.com/comments/' + userId)
      )
      
      return forkJoinWithProgress(arrayOfObservables)
    }
     
     
    const result$ = getUserDetails([1, 2, 15]);
     
    result$.pipe(
      mergeMap(([finalResult, progress]) => merge(
        progress.pipe(
          tap((value) => console.log(`${value} completed`)),
          ignoreElements()
        ),
        finalResult
      ))
    ).subscribe(values => console.log(values), console.warn);
     
    // Output:
    // 33.333333333333336 completed
    // 66.66666666666667 completed
    // 100 completed
    // final value:  (3) [{…}, {…}, {…}]

    Helper functions

    timeRange

    Function to create Observable that will emit values with specified delays

    Params:

    range - array of objects with special structure [{value: , delay: },...]

    isRelative - if true = next emissions is scheduled only after previous is complete (so delays are summarized).

    if false - all values are scheduled at once (delay values are absolute in relation to the moment of subscription)

     const range$ = timeRange([
       {value: 15, delay: 1500}, // 1500ms
       {value: 15, delay: 2500} // 2500ms
     ])
     
      const range2$ = timeRange([
       {value: 15, delay: 1500}, // 1500ms
       {value: 15, delay: 2500} // 1500+2500
     ], true);
     
    finalizeWithValue

    Provides (unlike original finalize from RxJS) source$'s last emitted value (if any) in format {value: }.

    If source$ completes with noe emitted value - provides undefined.

    Author - Ben Lesh, taken here

     
    from([1,3]).pipe(
      finalizeWithValue((lastEmittedValue) => console.log(lastEmittedValue)) // 3
    )
     

    Want to learn RxJS?

    Try my "Hands-on RxJS for Web Development" video-course!

    Install

    npm i rxjs-toolbox

    DownloadsWeekly Downloads

    135

    Version

    2.2.2

    License

    MIT

    Unpacked Size

    75.4 kB

    Total Files

    26

    Last publish

    Collaborators

    • kievsash