Request retrying

Request retrying in Alette Signal is a feature allowing request blueprints to rerun the failing request with identical request settings when a retry condition is met.

Retrying requests

To retry a request, pass the retry() middleware to the request blueprint:

const deletePost = mutation(
    retry({
		times: 2,
	})
)

DANGER

While a request is being retried, no errors are thrown.

WARNING

While a request is being retried, debouncing and throttling are ignored.

WARNING

The retry() middleware override previous retry() middleware:

const deletePost = mutation(
    retry({
        times: 2,
    })
)

const deleteDraftPost = deletePost.with(
    // This will override the "retry()" inferited
	// from the "deletePost" request blueprint
    retry({
        times: 5,
    })
)

Status-based retrying

To retry a failing request when a certain HTTP status is returned, configure the whenStatus property of the retry() middleware:

const deletePost = mutation(
    retry({
		times: 2,
		whenStatus: [401, 500, 429]
	})
)

To retry a request based unless a certain HTTP status is returned, configure the unlessStatus property of the retry() middleware:

const deletePost = mutation(
    retry({
		times: 2,
		unlessStatus: [401, 500, 429]
	})
)

DANGER

The whenStatus property overrides the unlessStatus property of the retry() middleware:

const deletePost = mutation(
    retry({
		times: 2,
		whenStatus: [401],
		// "unlessStatus" will be ignored
		unlessStatus: [401, 500, 429]
	})
)

Delay between retries

To add a delay between request retry attempts, configure the backoff property of the retry() middleware:

const deletePost = mutation(
    retry({
		times: 5,
		backoff: ["1 second", "5 seconds", "10 seconds"],
	})
)

// 1st retry
// Wait 1 second...
// 2nd retry
// Wait 5 seconds...
// 3rd retry
// Wait 10 seconds...
// 4th retry
// Wait 10 seconds...
// 5th retry
await deletePost.execute()

Retry condition

A retry condition is a function taking information about the failed request and returning true to allow for the request retry, or false to prohibit the request from being retried:

async ({ error, attempt }, { args: postId, path }) => {
    if (error.getStatus() === 429) {
        return true;
    }

    return postId === 5;
}

Custom retry

To create a custom retry, pass a retry condition to the retryWhen middleware:

import { wait, retryWhen, input, path } from '@alette/signal';
// ...

const deletePost = mutation(
    input(as<number>()),
    path('/posts'),
    retryWhen(async ({ error, attempt }, { args: postId, path }) => {
        if (error.getStatus() === 429) {
            await wait("5 seconds");
            return true;
		}

		return postId === 5;
	})
)

await deletePost.execute({ args: 3 })

To add a delay between retries inside a retryWhen() retry condition, use the wait() function provided by Alette Signal:

import { wait, /* ... */ } from '@alette/signal';

retryWhen(async ({ attempt }) => {
    if (attempt === 0) {
    	await wait(1000);
	}

    if (attempt === 1) {
        await wait("5 seconds");
    }

	await wait("10 seconds");
    return true;
})

TIP

Request data is available as a second argument of the retryWhen() retry condition:

retryWhen(async (_, { args: postId, path, context }) => {
    /* ... */
})

WARNING

While a request is being retried, debouncing and throttling are ignored.

WARNING

The retryWhen() middleware override previous retryWhen() middleware:

const deletePost = mutation(
    retryWhen(() => true)
)

const deleteDraftPost = deletePost.with(
    // This will override the "retryWhen()" inferited
	// from the "deletePost" request blueprint
    retryWhen(() => false)
)

Disabling retrying

To disable retrying per request, set the skipRetry request setting to true:

const deletePost = mutation(
    retryWhen(() => true)
);

// Won't be retried
await deletePost.execute({ skipRetry: true });
// Will be retried
await deletePost.execute();

TIP

The skipRetry request setting works with both retry() and retryWhen() middleware.