@upyo/retry

@upyo/retry provides a retry and backoff decorator for Upyo transports. It wraps any Transport implementation without changing the transport interface, so it can be composed with SMTP, HTTP API transports, pool transports, and OpenTelemetry instrumentation.

Installation

deno add jsr:@upyo/retry
pnpm add @upyo/retry

Usage

import { RetryTransport } from "@upyo/retry";
import { MailgunTransport } from "@upyo/mailgun";

const baseTransport = new MailgunTransport({
  apiKey: "your-mailgun-api-key",
  domain: "mg.example.com",
});

const transport = new RetryTransport(baseTransport, {
  maxAttempts: 3,
  backoff: {
    baseDelayMilliseconds: 1000,
    maxDelayMilliseconds: 30000,
    factor: 2,
  },
});

The retry transport uses structured Upyo failure receipts to distinguish transient failures, such as rate limits and temporary server errors, from permanent failures, such as validation or authentication errors. It also honors provider-supplied Retry-After metadata when available.