retry

Returns an Observable that mirrors the source Observable with the exception of an error.

retry<T>(configOrCount: number | RetryConfig = Infinity): MonoTypeOperatorFunction<T>

Parameters

configOrCount

number | RetryConfig

Optional. Default is Infinity. Either number of retry attempts before failing or a RetryConfig object.

Returns

MonoTypeOperatorFunction<T>: A function that returns an Observable that will resubscribe to the source stream when the source stream errors, at most count times.

Description

If the source Observable calls error, this method will resubscribe to the source Observable for a maximum of count resubscriptions rather than propagating the error call.

The number of retries is determined by the count parameter. It can be set either by passing a number to retry function or by setting count property when retry is configured using RetryConfig. If count is omitted, retry will try to resubscribe on errors infinite number of times.

Any and all items emitted by the source Observable will be emitted by the resulting Observable, even those emitted during failed subscriptions. For example, if an Observable fails at first but emits [1, 2] then succeeds the second time and emits: [1, 2, 3, 4, 5, complete] then the complete stream of emissions and notifications would be: [1, 2, 1, 2, 3, 4, 5, complete].

Example

import { interval, mergeMap, throwError, of, retry } from 'rxjs';

const source = interval(1000);
const result = source.pipe(
  mergeMap(val => val > 5 ? throwError(() => 'Error!') : of(val)),
  retry(2) // retry 2 times on error
);

result.subscribe({
  next: value => console.log(value),
  error: err => console.log(`${ err }: Retried 2 times then quit!`)
});

// Output:
// 0..1..2..3..4..5..
// 0..1..2..3..4..5..
// 0..1..2..3..4..5..
// 'Error!: Retried 2 times then quit!'

See Also

• retryWhen