temporalio__skill-temporal-developer/references/php/observability.md

PHP SDK Observability

Overview

The PHP SDK provides observability through PSR-3 logging (with replay-aware Workflow logger), and visibility via Search Attributes.

Logging

Workflow Logging

Use Workflow::getLogger() for replay-safe logging inside Workflows:

use Temporal\Workflow;

class OrderWorkflow implements OrderWorkflowInterface
{
    public function run(array $order): \Generator
    {
        Workflow::getLogger()->info('Workflow started', ['orderId' => $order['id']]);

        $result = yield $this->activity->processPayment($order);

        Workflow::getLogger()->info('Payment processed', ['result' => $result]);

        return $result;
    }
}

The Workflow logger automatically suppresses duplicate log messages during replay by default.

Activity Logging

Activities are not replayed, so use any standard PSR-3 logger (injected via constructor or DI):

use Psr\Log\LoggerInterface;

class OrderActivity implements OrderActivityInterface
{
    public function __construct(private LoggerInterface $logger) {}

    public function processPayment(array $order): string
    {
        $this->logger->info('Processing payment', ['orderId' => $order['id']]);

        // Perform work...

        $this->logger->info('Payment complete');
        return 'completed';
    }
}

Enabling Logging During Replay

By default, Workflow::getLogger() suppresses logs during replay. To enable logging during replay (useful for debugging):

use Temporal\Worker\WorkerOptions;

$worker = $factory->newWorker(
    taskQueue: 'orders',
    options: WorkerOptions::new()->withEnableLoggingInReplay(true)
);

Customizing the Logger

Pass a custom PSR-3 logger when creating the Worker:

use Monolog\Logger;
use Monolog\Handler\StreamHandler;
use Temporal\WorkerFactory;

$logger = new Logger('temporal');
$logger->pushHandler(new StreamHandler('php://stdout'));

$factory = WorkerFactory::create();

$worker = $factory->newWorker(
    taskQueue: 'my-task-queue',
    logger: $logger
);

Any PSR-3 compatible logger (Monolog, etc.) can be used.

Search Attributes (Visibility)

See the Search Attributes section of references/php/data-handling.md

Best Practices

1. Use Workflow::getLogger() inside Workflow code for replay-safe logging
2. Do not use echo or print() in Workflows — output appears on every replay
3. Use standard PSR-3 loggers in Activities (no replay concern)
4. Use Search Attributes for business-level visibility and querying across Workflow executions