Ecotone Interceptors

Overview

Interceptors are cross-cutting middleware that hook into handler execution. Use them for transactions, authorization, logging, validation, header enrichment, and other concerns that span multiple handlers.

Attribute	When	Flow Control	changeHeaders
`#[Presend]`	Before message enters channel	No	Yes
`#[Before]`	Before handler executes	No	Yes
`#[Around]`	Wraps handler execution	`MethodInvocation::proceed()`	No
`#[After]`	After handler completes	No	Yes

Execution order: Presend -> Before -> Around -> handler -> Around end -> After

Before Interceptor

php

use Ecotone\Messaging\Attribute\Interceptor\Before;

class ValidationInterceptor
{
    #[Before(pointcut: CommandHandler::class)]
    public function validate(object $command): void
    {
        // Throw exception to stop execution
    }
}

After Interceptor

php

use Ecotone\Messaging\Attribute\Interceptor\After;

class AuditInterceptor
{
    #[After(pointcut: CommandHandler::class)]
    public function audit(object $command): void
    {
        // Log after handler completes
    }
}

Around Interceptor

php

use Ecotone\Messaging\Attribute\Interceptor\Around;
use Ecotone\Messaging\Handler\Processor\MethodInvoker\MethodInvocation;

class TransactionInterceptor
{
    #[Around(precedence: Precedence::DATABASE_TRANSACTION_PRECEDENCE)]
    public function transactional(MethodInvocation $invocation): mixed
    {
        $this->connection->beginTransaction();
        try {
            $result = $invocation->proceed();
            $this->connection->commit();
            return $result;
        } catch (\Throwable $e) {
            $this->connection->rollBack();
            throw $e;
        }
    }
}

You must call proceed() or the handler chain stops.

Presend Interceptor

php

use Ecotone\Messaging\Attribute\Interceptor\Presend;

class AuthorizationInterceptor
{
    #[Presend(pointcut: CommandHandler::class)]
    public function authorize(object $command, #[Header('userId')] string $userId): void
    {
        if (! $this->authService->canExecute($userId, $command)) {
            throw new UnauthorizedException();
        }
    }
}

Pointcut System

Pointcuts target which handlers an interceptor applies to:

php

// By attribute
#[Before(pointcut: CommandHandler::class)]

// By class
#[Before(pointcut: OrderService::class)]

// By method
#[Before(pointcut: OrderService::class . '::placeOrder')]

// By namespace
#[Before(pointcut: 'App\Domain\*')]

// AND / OR / NOT
#[Before(pointcut: CommandHandler::class . '||' . EventHandler::class)]
#[Around(pointcut: CommandHandler::class . '&&not(' . WithoutTransaction::class . ')')]

Auto-Inference

When no explicit pointcut is set, it's inferred from the interceptor method's parameter type-hints:

php

#[Before]
public function check(RequiresAuth $attribute): void { }
// Auto-targets handlers with #[RequiresAuth]

Header Modification

php

#[Before(changeHeaders: true, pointcut: CommandHandler::class)]
public function addHeaders(#[Headers] array $headers): array
{
    $headers['processedAt'] = time();
    return $headers;
}

Only available on #[Before], #[After], #[Presend] (not #[Around]).

Key Rules

•Always call proceed() in #[Around] interceptors
•Use Precedence::DEFAULT_PRECEDENCE for custom interceptors
•Pointcuts can target attributes, classes, or interfaces
•Register interceptor classes in classesToResolve for testing
•Lower precedence value = runs earlier

Additional resources

•API Reference — Constructor signatures and parameter details for #[Before], #[After], #[Around], #[Presend] attributes, MethodInvocation interface, and Precedence constants table. Load when you need exact parameter names, types, defaults, or precedence values.
•Usage Examples — Full interceptor class implementations: transaction wrappers, validation, audit logging, authorization, correlation ID enrichment, argument modification via MethodInvocation, and complete pointcut patterns (attribute, class, namespace, method, AND/OR/NOT, bus targeting, custom attributes, dynamic pointcut building). Load when you need complete, copy-paste-ready interceptor implementations or complex pointcut expressions.
•Testing Patterns — EcotoneLite test setup for interceptors: verifying interceptor execution, testing execution order (before/around/after), and registering interceptors with classesToResolve. Load when writing tests for interceptors.