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https://github.com/tjenkinson/exponential-rate-limit

A small library which handles decaying exponential backoff. This is useful if you want to start throttling something whilst it is going wrong, but recover once things start working again.
https://github.com/tjenkinson/exponential-rate-limit

backoff decay delay exponential exponential-backoff retry typescript

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A small library which handles decaying exponential backoff. This is useful if you want to start throttling something whilst it is going wrong, but recover once things start working again.

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# Exponential Rate Limit
A small library which handles decaying exponential backoff. This is useful if you want to start throttling something whilst it is going wrong, but recover once things start working again.

## Demo
The demo source is in "[demo.ts](/src/demo.ts)".

To run the demo locally run `npm run start`.

It is also hosted [here](https://exponential-rate-limit.netlify.com/demo.html) (thanks to [Netify](https://www.netlify.com/)).

## Usage
```ts
import { JobQueue, defaultDelayFunction } from './exponential-rate-limit';

const queue = new JobQueue({
/**
* The maximum time (seconds) between jobs executing.
*/
maxInterval: 5
/**
* The delay function.
*/
delayFunction: defaultDelayFunction
});

const { remove } = queue.enqueue(({ enqueueTime } => {
console.log('Executing', enqueueTime);
});
```

## Example
The following example implements `throttledFetch`, which will start delaying future executions exponentially (up to the default 5 seconds) every time a request fails or does not respond with status 200.

Every time there is a 200 response, the delays will also start getting shorter again. As time passes without any jobs being executed, the delay the next job would incur also decreases.

```ts
import { JobQueue } from './exponential-rate-limit';

const jobQueue = new JobQueue(); // default options

function throttledFetch(...fetchArgs): Promise {
return new Promise((resolve) => {
jobQueue.enqueue(() => {
const fetchPromise = fetch(...fetchArgs);
resolve(fetchPromise);
return fetchPromise.then((response) => response.status === 200);
});
});
}
```

## Browser
This can also be used in the browser thanks to [jsDelivr](https://github.com/jsdelivr/jsdelivr):
```html



var queue = new ExponentialRateLimit.JobQueue();

```