【Angular活用講座】Rxjsでエラーレスポンスを上手にリトライするためのサービスを作る

            
            setInterval(() => {
    //...定期実行したい処理を記述
}, 1000);
        

            
            const { timer } = require('rxjs');

const timer$ = timer(1, 5000);

timer$.subscribe((val) => console.log(val));
        

            
            const { timer, switchMap } = require('rxjs');

//...中略

this.myInterval$ = timer(1, 5000).pipe(
    switchMap(_ => http.get('https://hoge.com/api'))
);
        

            
            const { timer, switchMap, retry } = require('rxjs');

//...中略

this.myInterval$ = timer(1, 5000).pipe(
    switchMap(_ => http.get('https://hoge.com/api')),
    retry()
);
        

            
            const { timer, switchMap, retry, share } = require('rxjs');

//...中略

this.myInterval$ = timer(1, 5000).pipe(
    switchMap(_ => http.get('https://hoge.com/api')),
    retry(),
    share()
);
        

            
            const { timer, switchMap, retry, share, Subject } = require('rxjs');

//...中略

private stopPolling = new Subject();

ngOnDestroy() {
    this.stopPolling.next(null);
}
        

            
            const { timer, switchMap, retry, share, Subject, takeUntil } = require('rxjs');

//...中略

private stopPolling = new Subject();

this.myInterval$ = timer(1, 5000).pipe(
    switchMap(_ => http.get('https://hoge.com/api')),
    retry(),
    share(),
    takeUntil(this.stopPolling)
);
        

            
            import { Injectable, OnDestroy } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import {
    Observable, timer, Subject,
    switchMap, share, retry, takeUntil
} from 'rxjs';

@Injectable({
    providedIn: 'root'
})
export class HogeService implements OnDestroy {
    private myInterval$: Observable<any>;
    private stopNotifier = new Subject();

    constructor(private http: HttpClient) {
        this.myInterval$ = timer(1, 5000).pipe(
            switchMap(_ => http.get<any>('https://hoge.com/api')),
            retry(),
            share(),
            takeUntil(this.stopNotifier)
        );
    }

    hogeInfo(): Observable<any> {
        return this.myInterval$;
    }

    ngOnDestroy() {
        this.stopNotifier.next(null);
    }
}