How to Properly Convert a Fetch Promise into an Observable in Ionic 5 using Typescript?

I'm in the process of transitioning my Ionic3 app to Ionic5 and currently working on integrating my http requests. I previously utilized angular/http in Ionic3, but it appears that it has been deprecated. This was how I handled observables in my code:

   this._http.get(requestURL)
      .map((result: Response) => {
        return this.run(result.json())
   });

Now that http is no longer available in Ionic5, what is the alternative approach to achieve the same functionality?

Rx.Observable.fromPromise(fetch(url));

However, it seems that the above method is not functioning correctly as 

fromPromise does not exist on Rx.Observeable
.

typescriptionic-frameworkrxjsionic5

Answer №1

For those utilizing RxJS 6, the recommended approach is to utilize the from operator instead. This operator will transform the promise into an observable:

const request = fetch(url);

from(request).pipe(
  switchMap(response => response.json()),
 ... perform other tasks here.
)

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