@nixjs23n6/backoff-typescript

A small library which handles decaying constant/linear/exponential backOff

Quick Setup

ConstantBackoff

The ConstantBackoff will make the websocket wait a constant time between each connection retry. To use the Constant Backoff with a wait-time of 1 second:

1const backoff  = new ConstantBackoff(1000)
2setTimeout(() => {
3    // todo something
4}, backoff)

LinearBackoff

The LinearBackoff linearly increases the wait-time between connection-retries until an optional maximum is reached. To use the LinearBackoff to initially wait 0 seconds and increase the wait-time by 2 second with every retry until a maximum of 12 seconds is reached:

1const backoff  = new LinearBackoff(0, 2000, 12000)
2setTimeout(() => {
3    // todo something
4}, backoff)

ExponentialBackoff

The ExponentialBackoff doubles the backoff with every retry until a maximum is reached. This is modelled after the binary exponential-backoff algorithm used in computer-networking. To use the ExponentialBackoff that will produce the series [100, 200, 400, 800, 1600, 3200, 6400]:

1const backoff  = new ExponentialBackoff(100, 7)
2setTimeout(() => {
3    // todo something
4}, backoff)

Examples

Redux-saga

1import { LinearBackOff, BaseBackOff } from '@nixjs23n6/backoff-typescript'
2
3function* pollPriceSaga(backOff: BaseBackOff) {
4    while (true) {
5        try {
6            const time = backOff.next()
7            if (time === 15000) {
8                backOff.reset()
9            }
10
11            const result = yield call(FETCH_PRICE)
12            yield put(onFetchPriceSuccess(result))
13            if (time > 0) yield delay(time)
14            yield delay(time)
15        } catch (err) {
16            yield put(onFetchPriceFailure(err))
17        }
18    }
19}
20
21function* watchPriceSaga() {
22    while (true) {
23        yield take(coingeckoSlice.onStartFetchPrice)
24
25        const backOff = new LinearBackOff(0, 10000, 15000)
26        yield race({
27            task: call(pollPriceSaga, backOff),
28            cancel: take(coingeckoSlice.onStopFetchPrice)
29        })
30    }
31}