README

A tiny set of PHP interfaces for standardized retry behavior, plus a compact rtry: string you can store in one column and compile at runtime.

Features

• Portable API: RetryerInterface::try(callable $op, RetryPolicyInterface $policy, array $context = []).
• Single‑column policy with rtry: strings (backoff, jitter, deadlines, hedging hints).
• Testable: ClockInterface + SleeperInterface → no real sleeps in unit tests.
• Deciders: pluggable logic to map outcomes to retry/stop decisions.

Quick start

use Psr\Retry\Impl\RtryPolicyFactory;
use Psr\Retry\Impl\RtryPolicy;
use foreup\rest\models\services\Retry;
use foreup\rest\models\services\NativeSleeper;
use Psr\Clock\ClockInterface;

// Construct runtime pieces (DI in real apps)
$factory = new RtryPolicyFactory();
$policy = $factory->fromSpec('rtry:a=5;d=250ms;mode=exp;b=2;cap=5s;jmode=full;on=5xx,ETIMEDOUT');

$retryer = new Retry($clock /* PSR-20 */, new NativeSleeper());

$response = $retryer->try(function ($ctx) use ($httpClient, $request) {
    $res = $httpClient->sendRequest($request);
    if ($res->getStatusCode() >= 500) {
        throw new RuntimeException('server_error');
    }
    return $res;
}, $policy, ['tenant_id' => 12345, 'correlation_id' => 'req-abc123']);

Interfaces (overview)

• RetryerInterface — runs the callable under a policy.
• RetryPolicyInterface — attempts, delays, jitter, deadlines, hedging hints, decider.
• RetryPolicyFactoryInterface — parses rtry: into a policy.
• AttemptContextInterface — attempt #, elapsed, remaining budget, context.
• AttemptOutcomeInterface — result or error for deciders.
• JitterSpecInterface — deterministic jitter application.
• RetryDeciderInterface — retry/stop decision.

See SPEC.md for normative details and the full RTRY grammar.

Testing

Provide a test SleeperInterface that records sleep calls instead of actually sleeping, and a fixed ClockInterface (PSR‑20) for deterministic timing.

Contributing

1. Open issues/PRs here to refine the draft.
2. If there’s interest, we’ll form a Working Group and seek a Sponsor inside PHP‑FIG.

License

• Code (interfaces, reference impl): MIT
• Spec/docs (SPEC.md, this README): CC‑BY 4.0

Attribution/NOTICE

© 2025 Gregory Riley and contributors. Licensed under Creative Commons Attribution 4.0 (CC BY 4.0). Changes may have been made. License: https://creativecommons.org/licenses/by/4.0/

Reference implementation (non-normative)

A production-ready reference implementation lives here:

• Repo: https://github.com/Gohany/Rtry
• Packagist: gohany/rtry (MIT)

This implementation is provided to demonstrate how the interfaces and the rtry: policy can be used in practice. It is non-normative and does not change the meaning of this spec.