在Angular NGRX效果中链接两个API调用

import { Injectable } from '@angular/core';
import { Actions, createEffect, ofType } from '@ngrx/effects';
import { mergeMap, map } from 'rxjs/operators';
import { ApiService } from './api.service';
import { firstApiCallSuccess, secondApiCallSuccess } from './actions';

@Injectable()
export class ApiEffects {
  constructor(private actions$: Actions, private apiService: ApiService) {}

  firstApiCall$ = createEffect(() =>
    this.actions$.pipe(
      ofType('First API Call'),
      mergeMap(() =>
        this.apiService.firstApiCall().pipe(
          map(response => firstApiCallSuccess({ data: response }))
        )
      )
    )
  );

  secondApiCall$ = createEffect(() =>
    this.actions$.pipe(
      ofType('Second API Call'),
      mergeMap(() =>
        this.apiService.secondApiCall().pipe(
          map(response => secondApiCallSuccess({ data: response }))
        )
      )
    )
  );
}

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { Observable } from 'rxjs';

@Injectable()
export class ApiService {
  constructor(private http: HttpClient) {}

  firstApiCall(): Observable<any> {
    return this.http.get('https://api.example.com/first');
  }

  secondApiCall(): Observable<any> {
    return this.http.get('https://api.example.com/second');
  }
}

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { HttpClientModule } from '@angular/common/http';
import { EffectsModule } from '@ngrx/effects';

import { AppComponent } from './app.component';
import { ApiEffects } from './api.effects';
import { ApiService } from './api.service';

@NgModule({
  imports: [
    BrowserModule,
    HttpClientModule,
    EffectsModule.forRoot([ApiEffects])
  ],
  declarations: [AppComponent],
  providers: [ApiService],
  bootstrap: [AppComponent]
})
export class AppModule {}