angular - Rxjs observable batch before execute -


i'm trying build function get's id , send server , return response. far good.. issue function may called lot of times, want achieve following: function get's id, wait 3 seconds , execute. if id been passed during 3 seconds, append to id's sent , start 3 seconds count again. after 3 seconds pass, send id's (in single request) , return response every id sender.

so far try use subject , buffer operator :

  batchplacebetsubscription:subject<string>=new subject();   batchplacebetsubscription:observable<response>;    sendtoserver(id: string): observable<any> {     this.batchplacebetsubscription.next(id);     return this.batchplacebetsubscription$;    }    private placebetbatchrequests(placebetitem: iplacebet[]) {     this.batchplacebetsubscription$ = this.batchplacebetsubscription       .buffer(observable.timer(0, 3000))       .take(1)       .switchmap(idsarray => {         debugger;         return this.http.post('http://someurl,idsarray)           .map(res => res.json())           .catch(e => observable.throw(e))       })       }

this work's first id been ignored (i guess because when subject 'next' it, there not subscribers yet).

so, how can batch id's? in advance.


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