Retry Pattern Generator

Creates Retry pattern infrastructure for handling transient failures.

When to Use

Scenario	Example
Transient failures	Network timeouts, temporary unavailability
External API calls	HTTP requests to third-party services
Database operations	Deadlock recovery, connection issues
Message processing	Queue message handling with retries

Component Characteristics

RetryPolicy

• Configures retry behavior
• Maximum attempts
• Delay strategy (fixed, exponential, linear)
• Jitter support to prevent thundering herd

RetryExecutor

• Executes operations with retry logic
• Tracks attempt count
• Applies delay between retries
• Logs retry attempts

Backoff Strategies

• Fixed: Same delay every time
• Linear: Delay increases linearly
• Exponential: Delay doubles (with optional jitter)

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Generation Process

Step 1: Generate Core Components

Path: src/Infrastructure/Resilience/Retry/

1. BackoffStrategy.php — Enum for delay strategies
2. RetryPolicy.php — Configuration with shouldRetry/calculateDelay
3. RetryContext.php — Attempt context value object
4. RetryException.php — Exception with attempt history

Step 2: Generate Executor

Path: src/Infrastructure/Resilience/Retry/

1. RetryExecutor.php — Main retry logic with callbacks
2. SleepInterface.php — For testability

Step 3: Generate Tests

1. RetryPolicyTest.php — Policy behavior tests
2. RetryExecutorTest.php — Executor tests

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File Placement

Component	Path
All Classes	src/Infrastructure/Resilience/Retry/
Unit Tests	tests/Unit/Infrastructure/Resilience/Retry/

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Naming Conventions

Component	Pattern	Example
Policy	RetryPolicy	RetryPolicy
Strategy Enum	BackoffStrategy	BackoffStrategy
Executor	RetryExecutor	RetryExecutor
Context	RetryContext	RetryContext
Exception	RetryException	RetryException
Test	{ClassName}Test	RetryExecutorTest

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Quick Template Reference

RetryPolicy

final readonly class RetryPolicy
{
    public function __construct(
        public int $maxAttempts = 3,
        public int $baseDelayMs = 100,
        public int $maxDelayMs = 10000,
        public float $multiplier = 2.0,
        public bool $useJitter = true,
        public BackoffStrategy $strategy = BackoffStrategy::Exponential,
        public array $retryableExceptions = [],
        public array $nonRetryableExceptions = []
    ) {}

    public static function exponential(int $maxAttempts = 5, int $baseDelayMs = 100): self;
    public static function linear(int $maxAttempts = 5, int $baseDelayMs = 500): self;
    public function shouldRetry(\Throwable $e, int $attempt): bool;
    public function calculateDelay(int $attempt): int;
}

RetryExecutor

final readonly class RetryExecutor
{
    public function execute(
        callable $operation,
        RetryPolicy $policy,
        ?callable $onRetry = null
    ): mixed;
}

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Usage Example

$policy = new RetryPolicy(
    maxAttempts: 3,
    baseDelayMs: 200,
    retryableExceptions: [
        ConnectionException::class,
        TimeoutException::class,
    ],
    nonRetryableExceptions: [
        ClientException::class,
    ]
);

try {
    $result = $retryExecutor->execute(
        operation: fn() => $httpClient->get($url),
        policy: $policy,
        onRetry: fn($e, $ctx) => $logger->warning('Retrying...', ['attempt' => $ctx->attempt])
    );
} catch (RetryException $e) {
    // All retries exhausted
    $deadLetter->send($message, $e);
}

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Anti-patterns to Avoid

Anti-pattern	Problem	Solution
No Max Attempts	Infinite retries	Always set maxAttempts
No Backoff	Hammering service	Use exponential backoff
Retrying All Exceptions	Retrying unrecoverable errors	Specify retryable exceptions
No Jitter	Thundering herd	Enable jitter
Ignoring Context	Can't track attempts	Use RetryContext
Blocking Forever	Thread exhaustion	Set maxDelayMs cap

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References

For complete PHP templates and examples, see:

• references/templates.md — RetryPolicy, BackoffStrategy, RetryExecutor, RetryContext templates
• references/examples.md — HTTP client, database, message consumer examples and tests