@variablesoftware/ts-retry-backoff/dist/index.js

🎛️🔁🚀 A tiny, zero‑dependencies retry helper with exponential backoff + jitter—usable for KV, HTTP, Durable Objects, or any async function.

// src/index.ts (or wherever your entrypoint is)
export const strategies = {
    exponential: (n, base) => base * 2 ** n,
    linear: (n, base) => base * (n + 1),
    fibonacci: (n, base) => {
        let a = 0, b = 1;
        for (let i = 0; i < n; i++)
            [a, b] = [b, a + b];
        return a * base;
    }
};
export function delay(ms, signal) {
    if (signal?.aborted) {
        // DOMException so it matches fetch/stream aborts
        throw new DOMException('Aborted', 'AbortError');
    }
    return new Promise((resolve, reject) => {
        const timer = setTimeout(() => {
            signal?.removeEventListener('abort', onAbort);
            resolve();
        }, ms);
        const onAbort = () => {
            clearTimeout(timer);
            reject(new DOMException('Aborted', 'AbortError'));
        };
        signal?.addEventListener('abort', onAbort, { once: true });
    });
}
export async function retryBackoff(fn, opts = {}) {
    const { maxRetries = 5, baseDelayMs = 50, minDelayMs, maxDelayMs, strategy = strategies.exponential, jitter = 0, retryOn = () => true, onRetry = () => { }, onSuccess = () => { }, onGiveUp = () => { }, signal } = opts;
    let attempt = 0;
    while (true) {
        if (signal?.aborted)
            throw new DOMException('Aborted', 'AbortError');
        try {
            const result = await fn();
            onSuccess(result, attempt);
            return result;
        }
        catch (err) {
            if (attempt >= maxRetries || !retryOn(err)) {
                onGiveUp(err, attempt);
                throw err;
            }
            let rawDelay = strategy(attempt, baseDelayMs);
            if (typeof minDelayMs === 'number')
                rawDelay = Math.max(rawDelay, minDelayMs);
            if (typeof maxDelayMs === 'number')
                rawDelay = Math.min(rawDelay, maxDelayMs);
            const delayWithJitter = rawDelay + (jitter > 0 ? Math.random() * rawDelay * jitter : 0);
            onRetry(err, attempt, delayWithJitter);
            await delay(delayWithJitter, signal);
            attempt++;
        }
    }
}