Addressed service.name issue

Author: jerrytfleung

src/Propagation/ServiceName/src/ServiceNamePropagator.php

@@ -20,10 +20,8 @@
  */
 final class ServiceNamePropagator implements TextMapPropagatorInterface
 {
-    private const SERVICE_NAME = 'service.name';
-
     private const FIELDS = [
-        self::SERVICE_NAME,
+        ResourceAttributes::SERVICE_NAME,
     ];
 
     private static ?self $instance = null;
@@ -59,7 +57,7 @@ public function inject(&$carrier, ?PropagationSetterInterface $setter = null, ?C
         $resource = $detector->getResource();
 
         if ($resource->getAttributes()->has(ResourceAttributes::SERVICE_NAME)) {
-            $setter->set($carrier, self::SERVICE_NAME, $resource->getAttributes()->get(ResourceAttributes::SERVICE_NAME));
+            $setter->set($carrier, ResourceAttributes::SERVICE_NAME, $resource->getAttributes()->get(ResourceAttributes::SERVICE_NAME));
         }
     }
 

src/Propagation/ServiceName/tests/Unit/ServiceNamePropagatorTest.php

@@ -6,6 +6,7 @@
 
 use OpenTelemetry\Context\Context;
 use OpenTelemetry\Contrib\Propagation\ServiceName\ServiceNamePropagator;
+use OpenTelemetry\SemConv\ResourceAttributes;
 use Override;
 use PHPUnit\Framework\TestCase;
 
@@ -22,7 +23,7 @@ protected function setUp(): void
     public function test_fields(): void
     {
         $this->assertSame(
-            ['service.name'],
+            [ResourceAttributes::SERVICE_NAME],
             $this->serviceNamePropagator->fields()
         );
     }
@@ -39,7 +40,7 @@ public function test_inject(): void
         putenv('OTEL_SERVICE_NAME=foo-service');
         $carrier = [];
         $this->serviceNamePropagator->inject($carrier);
-        $this->assertEquals($carrier, ['service.name'=>'foo-service']);
+        $this->assertEquals($carrier, [ResourceAttributes::SERVICE_NAME=>'foo-service']);
         putenv('OTEL_SERVICE_NAME');
     }
 
@@ -52,7 +53,7 @@ public function test_extract_empty(): void
 
     public function test_no_extract(): void
     {
-        $carrier = ['service.name' => 'foo-service'];
+        $carrier = [ResourceAttributes::SERVICE_NAME => 'foo-service'];
         $context = $this->serviceNamePropagator->extract($carrier);
         $this->assertSame(Context::getCurrent(), $context);
     }