Retry Handler

Automatic retry logic with exponential backoff and configurable strategies.

Installation

npm install retry-handler

Quick Start

import { retry, withRetry } from 'retry-handler';

// Retry an async function
const result = await retry(async () => {
  return await fetchData();
});

// Wrap a function with retry logic
const fetchWithRetry = withRetry(fetchData, { maxRetries: 5 });
await fetchWithRetry();

API

retry(fn, options)

await retry(async (attempt) => {
  console.log(`Attempt ${attempt + 1}`);
  return await apiCall();
}, {
  maxRetries: 3,           // Number of retries
  baseDelay: 1000,         // Initial delay (ms)
  maxDelay: 30000,         // Maximum delay (ms)
  factor: 2,               // Exponential factor
  jitter: true,            // Add randomization
  jitterFactor: 0.2,       // Jitter amount (±20%)
  timeout: 5000,           // Per-attempt timeout
  shouldRetry: (err) => true,  // Retry condition
  onRetry: (err, attempt, delay) => {}  // Hook
});

Backoff Strategies

// Exponential (default)
retry(fn, { factor: 2 })  // 1s, 2s, 4s, 8s...

// Linear
retryLinear(fn, { delay: 1000 })  // 1s, 2s, 3s, 4s...

// Fixed (no backoff)
retryFixed(fn, { delay: 1000 })  // 1s, 1s, 1s...

withRetry(fn, options)

Create a retryable version of any function:

const robustFetch = withRetry(fetch, { maxRetries: 3 });
await robustFetch('/api/data');

Retry Conditions

import { retryConditions } from 'retry-handler';

// Retry on network errors
retry(fn, { shouldRetry: retryConditions.networkError });

// Retry on specific HTTP status codes
retry(fn, { shouldRetry: retryConditions.httpStatus([500, 502, 503]) });

// Always/never retry
retry(fn, { shouldRetry: retryConditions.always });
retry(fn, { shouldRetry: retryConditions.never });

RetryableOperation

For more control:

const op = new RetryableOperation(fn, options);

try {
  await op.execute();
} catch (error) {
  console.log('Failed after', op.getAttempts(), 'retries');
  console.log('Errors:', op.getErrors());
}

// Abort in-progress operation
op.abort();

License

MIT