alex-okrushko

import {fromEvent} from 'rxjs';
import {sampleTime, startWith, switchMap} from 'rxjs/operators';
import {intervalBackoff} from 'backoff-rxjs';
import {service} from './service';

const newData$ = fromEvent(document, 'mousemove').pipe(
  
    // There could be many mousemoves, we'd want to sample only
    // with certain frequency
    sampleTime(1000),

alex-okrushko

// Determine if the error matches our expected type
// http://www.typescriptlang.org/docs/handbook/advanced-types.html#user-defined-type-guards
function isHttpError(error: {}): error is HttpError {
  // This is a type guard for interface
  // if HttpError was a class we would use instanceof check instead 
  return (error as HttpError).status !== undefined;
}

message$ = of('Call me!').pipe(
    tap(console.log),

alex-okrushko

import { Injectable } from '@angular/core';
import { of, throwError, defer } from 'rxjs';

export interface HttpError {
  error: string,
  status: string,
}

const ERROR_404: HttpError = { error: 'No need to try anymore', status: '404' };
const ERROR_503: HttpError = { error: 'Try again?', status: '503' };

alex-okrushko

import { Component } from '@angular/core';
import { of } from 'rxjs';
import { tap, switchMap} from 'rxjs/operators';
import { retryBackoff } from 'backoff-rxjs';
import { BackendService, HttpError } from './backend.service';

export const INIT_INTERVAL_MS = 100; // 100 ms
export const MAX_INTERVAL_MS = 20 * 1000; // 20 sec

@Component({

alex-okrushko

export interface RetryBackoffConfig {
  initialInterval: number;
  maxRetries?: number;
  maxInterval?: number;
  shouldRetry?: (error: any) => boolean;
  backoffDelay?: (iteration: number, initialInterval: number) => number;
}

alex-okrushko

export interface IntervalBackoffConfig {
  initialInterval: number;
  maxInterval?: number;
  backoffDelay?: (iteration: number, initialInterval: number) => number;
}