Slim SDK — Apirelio Documentation

Quickstart

Install the Slim adapter.

Composer installs the shared PHP Core automatically. Configure a project key, stable service name and deployment environment.

Terminalbash

composer require apirelio/slim:^0.1

.envbash

APIRELIO_API_KEY=apr_live_your_key
APIRELIO_ENDPOINT=https://apirelio.com
APIRELIO_SERVICE=billing-api
APIRELIO_ENVIRONMENT=production
APIRELIO_RELEASE=2026.08.12.1

Automatic tracking

Respect Slim's LIFO stack.

Add Apirelio before routing middleware. Slim then resolves the route before Apirelio runs, while error middleware remains the outermost exception boundary.

public/index.phpphp

use Apirelio\Slim\ApirelioMiddleware;
use Apirelio\Slim\Config;

$apirelio = new ApirelioMiddleware(new Config(
    apiKey: $_ENV['APIRELIO_API_KEY'],
    endpoint: $_ENV['APIRELIO_ENDPOINT'],
    service: $_ENV['APIRELIO_SERVICE'],
    environment: $_ENV['APIRELIO_ENVIRONMENT'],
    release: $_ENV['APIRELIO_RELEASE'] ?? null,
    paths: ['/api/*'],
    bufferPath: __DIR__.'/../var/apirelio/events.ndjson',
));

// Slim middleware is LIFO. Keep this order.
$app->add($apirelio);
$app->addRoutingMiddleware();
$app->addErrorMiddleware(false, true, true);

Why the order matters

The SDK needs Slim's route pattern such as /api/customers/{id}, not a high-cardinality concrete URL.

Customer context

Connect authentication to account identity.

Resolvers run after upstream authentication middleware and translate your domain objects into stable customer and consuming-application identifiers.

Apirelio middlewarephp

use Apirelio\Core\Data\ApirelioApplication;
use Apirelio\Core\Data\ApirelioCustomer;

$apirelio = new ApirelioMiddleware(
    config: $config,
    customerResolver: static fn ($request) => new ApirelioCustomer(
        id: (string) $request->getAttribute('account')->id,
        name: $request->getAttribute('account')->name,
        plan: $request->getAttribute('account')->plan,
    ),
    applicationResolver: static fn ($request) => new ApirelioApplication(
        id: (string) $request->getAttribute('api_client')->id,
        name: $request->getAttribute('api_client')->name,
    ),
);

Diagnostics

Add bounded request context.

The middleware attaches a mutable request context. Only configured scalar metadata survives PHP Core privacy filtering.

Slim routephp

use Apirelio\Slim\RequestContext;

$app->post('/api/invoices', function ($request, $response) {
    /** @var RequestContext|null $context */
    $context = $request->getAttribute(RequestContext::ATTRIBUTE);
    $context?->addMetadata(['region' => 'eu-central']);
    $context?->setErrorCode('PAYMENT_REQUIRED');

    return $response;
});

Reliability

Use a locked local buffer.

Configure a writable NDJSON buffer to keep normal requests away from network delivery. Transport failures are contained and never replace the customer response.

Buffered deliveryphp

new Config(
    // ...
    bufferPath: __DIR__.'/../var/apirelio/events.ndjson',
    batchSize: 500,
    flushIntervalSeconds: 10,
)

Privacy boundary

Operational metadata only.

✓

Captured

Method, route pattern, status, duration, byte counts and bounded identity.

Excluded

Request and response bodies, query strings, cookies, credentials and exception messages.

Fail-safe

SDK or ingestion failures cannot change Slim's response or exception flow.

Instrument Slim 4 APIs.