Styjun

Hi I am having trouble with my subject subscription and my search call. I want to cancel the previous call in favor of the current one. I have search through previous threads but have not had success with finding an answer.

I know I am supposed to use switchMap() but I am not having success with it. It continues all calls regardless of state. I think it mught have to do with the way I have set things up, in that I am not returning the response I am setting it. So there is no single observable reference..?

All help is appreciated!

Please see code below:

ngOnInit() 
// I subscribe to the Subject Observable here
this._searchService.quickSearch$
 .pipe(
 debounceTime(1000),
 distinctUntilChanged()
 )
 .subscribe(
 // when value has changed I call runSearch
 (queryString) => this.runSearch(queryString);
 
 );

runSearch:

runSearch(searchString: any) 
this.quickSearch.runSearch(searchString).pipe(
 //Not working as expected
 switchMap(() => 
 console.log('switchMap has bee fired');
 return this.quickSearch.runSearch(searchString);
 )
).subscribe(
 (response) => 
 // set the two way bind here
 this.apiResponse = response;
 ,
 (error) => 
 console.log('ERROR!!!');
 ,
 () => 
 // this is fired when the observable is closed
 console.log('I have been unsubscribed');
 
 );
 

quicksearch service:

 runSearch(search: string): Observable<QuickSearch[]> 

 ...

 return this.http.get<QuickSearch[]>(this.api.url, params: param, headers: header )
 .pipe(
 map((data: any) => 
 return data.map((item: any[]) => this.adapter.adapt(item));
 
 ),
 catchError(error => error)
 );

 

Thanks

UPDATE

I still have not found the answer to this question. So I am going to try to rephrase it.

I have 5 parts to this:

 Input box ([])-> 
 rxjs-Subject (input-text)-> 
 runSearch(input-text) -> [ handles response ] 
 _service.runSearch(input-text) ->
 http().get(input-text) => response

when the input box is changed then run search is called in which the search service is subscribed too this does not return

The problem is that every time this._searchService.quickSearch$ emits you're calling runSearch method that every time creates a new chain so even when you have switchMap it makes no difference.

Instead you should put switchMap to the first chain:

this._searchService.quickSearch$
 .pipe(
 debounceTime(1000),
 distinctUntilChanged(),
 switchMap((searchString) => this.quickSearch.runSearch(searchString)),
 ).subscribe(
 (response) => 
 this.apiResponse = response;
 ,
 ...
 );