Merge pull request #76 from wadjei/update-symfony-kernel-listener-example

Update the TracingKernelSubscriber example

Author: brettmc

src/Symfony/OtelSdkBundle/README.md

@@ -199,28 +199,31 @@ So our Listener class could look like this:
 namespace App\EventSubscriber;
 
 use OpenTelemetry\API\Trace\SpanInterface;
-use OpenTelemetry\SDK\Trace\Tracer;
+use OpenTelemetry\SDK\Trace\TracerProvider;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
 use Symfony\Component\HttpKernel\Event\RequestEvent;
 use Symfony\Component\HttpKernel\Event\TerminateEvent;
 use Symfony\Component\HttpKernel\KernelEvents;
 
 class TracingKernelSubscriber implements EventSubscriberInterface
 {
-    private Tracer $tracer;
+    private TracerProvider $provider;
     private ?SpanInterface $mainSpan = null;
 
-    public function __construct(Tracer $tracer)
+    public function __construct(TracerProvider $provider)
     {
-        // store a reference to the Tracer instance in case we want to create
+        // store a reference to the TracerProvider in case we want to create
         // more spans on different events (not covered in this example)
-        $this->tracer = $tracer;
+        $this->provider = $provider;
     }
 
     public function onRequestEvent(RequestEvent $event)
     {
         // Create our main span and activate it
-        $this->mainSpan = $this->tracer->spanBuilder('main')->startSpan();
+        $this->mainSpan = $this->provider
+            ->getTracer('io.opentelemetry.contrib.php')
+            ->spanBuilder('main')
+            ->startSpan();
         $this->mainSpan->activate();
     }