CODEWITHSUNDEEP
javascriptangularrxjs
vardius
vardius

Reputation: 6546

How can i retry after catch?

How can i retry after catch ?

I want to retry my observable after catch method automatically without calling another subscribe. How can i do that ?

I have something like this for now:

intercept(observable: Observable<Response>): Observable<Response> {
        return observable.catch((err, source) => {                
                return this.refreshToken()
                    .flatMap(res => {
                        if (res.status === 200) {
                            return observable;
                        }
                        return Observable.throw(new Error('Can\'t refresh the token'));
                    });
        });
    }

So when i have my observable and call subscribe on it it will catch error -> refresh token -> and then return observable where i have to call another subscribe. I dont want to do that. how can i make it work with that subscribe before ?

The call example will looke something like this:

let request = this.http.request(url);
intercept(request).subscribe(res => { //do something });

Upvotes: 1

Views: 2973

Answers (1)

user3743222
user3743222

Reputation: 18665

There are a couple of operators which can be used in conjunction with catch to handle retrial/repetition. They are useful operators, they allow you to conditionally resubscribe to observables which have terminated. From the official documentation for retryWhen :

Repeats the source observable sequence on error when the notifier emits a next value. If the source observable errors and the notifier completes, it will complete the source sequence.

Additional info here :

You can find some examples here from previous questions:

From the second SO question :

src.retryWhen(function (errors) {
    // retry for some errors, end the stream with an error for others
    return errors.do(function (e) {
        if (!canRetry(e)) {
            throw e;
        }
    });
});

Upvotes: 3

Related Questions