Angular 4 - Call database API only once for 2 components -


gurus, please help.

  1. service - having method getconfig() fetch data database , storing output in behavioursubject observable configarray$

  2. app.component.ts - calls getconfig() first , emits output configarray$

  3. status.component.ts - using resolver route prepopulate data component needs same data/output got app.component.ts getconfig() aip call.

i tried different approaches using setinterval, promise, observable wait appl.component.ts getconfig() method completed pass status.component.ts resolver route, non of working.

i not sure doing correct, can please how address requirement?

thank you.

code:

thank catalyst quick response. here complete code:

config.service.ts

@injectable() export class configservice {   private configsarray = new behaviorsubject<config>(undefined);   configsarray$ = this.configsarray.asobservable().first();   updateconfigs(configs: config) {     this.configsarray.next(configs)   }    getconfigs() {     let initialload: number = 0;     let initialloaddone: boolean = false;     if (this.fetchconfigs) == 'notfetched') {        // if meets if condition working        let headers = new headers();        headers.append('content-type','application/json');        this.updatefetchconfigs('fetching');        return this.http.get('http://localhost:8080/sample1/api/config', { headers: headers }).map((response: response) => response.json());     }     else {        // if not meet if condition not working        observable.interval(1)        .takewhile(() => !initialloaddone)        .subscribe(() => {            ++initialload;           if (this.getconfigs1(this.fetchconfigs$) == 'fetched' || initialload > 10000) {              initialloaddone = true;              return this.configsarray$;           }        });     }   } }

config-resolver.service.ts

@injectable() export class configresolver implements resolve<config> {   config: config;    constructor(private configservice: configservice, private router:router) {}    resolve(route: activatedroutesnapshot, state: routerstatesnapshot): observable<config> | promise<config> | config {     return this.configservice.getconfigs().map(            data => {         return data;       }     );   }  }

status.component.ts

export class statuscomponent implements oninit, ondestroy {    constructor(private configservice:configservice,               private route: activatedroute,               private router: router) {}    ngoninit() {     this.configsubscription = this.route.data.subscribe(         (data: data) => {           this.test = data['config'];         }     );   }  }


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