store root span info directly in context instead of request attribute

open-telemetry · Nov 15, 2022 · da19a11 · da19a11
1 parent f0e6db3
commit da19a11
Show file tree

Hide file tree

Showing 2 changed files with 12 additions and 7 deletions.
diff --git a/src/Instrumentation/Psr15/src/Psr15Instrumentation.php b/src/Instrumentation/Psr15/src/Psr15Instrumentation.php
@@ -7,10 +7,10 @@
 use OpenTelemetry\API\Common\Instrumentation\CachedInstrumentation;
 use OpenTelemetry\API\Common\Instrumentation\Globals;
 use OpenTelemetry\API\Trace\Span;
-use OpenTelemetry\API\Trace\SpanInterface;
 use OpenTelemetry\API\Trace\SpanKind;
 use OpenTelemetry\API\Trace\StatusCode;
 use OpenTelemetry\Context\Context;
+use OpenTelemetry\Context\ContextKey;
 use function OpenTelemetry\Instrumentation\hook;
 use OpenTelemetry\SemConv\TraceAttributes;
 use Psr\Http\Message\ResponseInterface;
@@ -24,6 +24,8 @@
  */
 class Psr15Instrumentation
 {
+    public static ContextKey $rootSpanExists;
+
     public static function register(): void
     {
         $instrumentation = new CachedInstrumentation('io.opentelemetry.contrib.php.psr15');
@@ -68,9 +70,7 @@ public static function register(): void
             'handle',
             pre: static function (RequestHandlerInterface $handler, array $params, string $class, string $function, ?string $filename, ?int $lineno) use ($instrumentation) {
                 $request = ($params[0] instanceof ServerRequestInterface) ? $params[0] : null;
-                $root = $request
-                    ? $request->getAttribute(SpanInterface::class)
-                    : Span::getCurrent();
+                $root = Context::getCurrent()->get(Psr15Instrumentation::$rootSpanExists);
                 $builder = $instrumentation->tracer()->spanBuilder(
                     $root
                     ? sprintf('%s::%s', $class, $function)
@@ -85,14 +85,14 @@ public static function register(): void
                 if (!$root && $request) {
                     //create http root span
                     $parent = Globals::propagator()->extract($request->getHeaders());
+                    $parent = $parent->with(Psr15Instrumentation::$rootSpanExists, true);
                     $span = $builder
                         ->setParent($parent)
                         ->setAttribute(TraceAttributes::HTTP_URL, $request->getUri()->__toString())
                         ->setAttribute(TraceAttributes::HTTP_METHOD, $request->getMethod())
                         ->setAttribute(TraceAttributes::HTTP_REQUEST_CONTENT_LENGTH, $request->getHeaderLine('Content-Length'))
                         ->setAttribute(TraceAttributes::HTTP_SCHEME, $request->getUri()->getScheme())
                         ->startSpan();
-                    $request = $request->withAttribute(SpanInterface::class, $span);
                 } else {
                     $span = $builder->startSpan();
                 }
@@ -125,3 +125,5 @@ public static function register(): void
         );
     }
 }
+
+Psr15Instrumentation::$rootSpanExists = Context::createKey('rootSpanExists');
diff --git a/src/Instrumentation/Psr15/tests/Integration/Psr15InstrumentationTest.php b/src/Instrumentation/Psr15/tests/Integration/Psr15InstrumentationTest.php
@@ -14,6 +14,7 @@
 use OpenTelemetry\API\Trace\Span;
 use OpenTelemetry\API\Trace\SpanInterface;
 use OpenTelemetry\Context\ScopeInterface;
+use OpenTelemetry\Context\Context;
 use OpenTelemetry\SDK\Trace\SpanExporter\InMemoryExporter;
 use OpenTelemetry\SDK\Trace\SpanProcessor\SimpleSpanProcessor;
 use OpenTelemetry\SDK\Trace\TracerProvider;
@@ -23,6 +24,7 @@
 use Psr\Http\Message\ServerRequestInterface;
 use Psr\Http\Server\MiddlewareInterface;
 use Psr\Http\Server\RequestHandlerInterface;
+use OpenTelemetry\Contrib\Instrumentation\Psr15\Psr15Instrumentation;
 
 class Psr15InstrumentationTest extends TestCase
 {
@@ -161,8 +163,9 @@ public function handle(ServerRequestInterface $request): ResponseInterface
                 if ($this->exception) {
                     throw $this->exception;
                 }
-                $span = $request->getAttribute(SpanInterface::class);
-                Assert::assertInstanceOf(Span::class, $span);
+                $rootSpanExists = Context::getCurrent()->get(Psr15Instrumentation::$rootSpanExists);
+                Assert::assertNotNull($rootSpanExists);
+                Assert::assertTrue($rootSpanExists);
 
                 return new Response();
             }