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- tidy constructor
- do not use a WeakMap to track prepared statements, as the SpanContext is lost when prepare span flushed/exported

Author: brettmc

src/Instrumentation/Doctrine/src/DoctrineInstrumentation.php

@@ -185,6 +185,7 @@ public static function register(): void
             }
         );
     }
+
     private static function makeBuilder(
         CachedInstrumentation $instrumentation,
         string $name,

src/Instrumentation/Doctrine/src/DoctrineTracker.php

@@ -6,28 +6,24 @@
 
 use Doctrine\DBAL\Driver\Statement;
 use OpenTelemetry\API\Trace\SpanContextInterface;
-use WeakMap;
-use WeakReference;
 
 /**
  * @internal
  */
 class DoctrineTracker
 {
-    private WeakMap $statementToSpanContextMap;
-
-    public function __construct()
-    {
-        $this->statementToSpanContextMap = new WeakMap();
+    public function __construct(
+        private \SplObjectStorage $statementToSpanContextMap = new \SplObjectStorage(),
+    ) {
     }
 
     public function trackStatement(Statement $statement, SpanContextInterface $context): void
     {
-        $this->statementToSpanContextMap[$statement] = WeakReference::create($context);
+        $this->statementToSpanContextMap[$statement] = $context;
     }
 
     public function getSpanContextForStatement(Statement $statement): ?SpanContextInterface
     {
-        return $this->statementToSpanContextMap[$statement]?->get();
+        return $this->statementToSpanContextMap[$statement] ?? null;
     }
 }

src/Instrumentation/Doctrine/tests/Integration/DoctrineInstrumentationTest.php

@@ -138,6 +138,21 @@ public function test_prepare_then_execute_statement(): void
         $this->assertEquals($prepare->getContext(), $execute->getLinks()[0]->getSpanContext(), 'execute span is linked to prepare span');
     }
 
+    public function test_tracked_span_context_when_prepare_span_flushed(): void
+    {
+        $connection =  self::createConnection();
+        $statement = self::fillDB();
+        $connection->executeStatement($statement);
+
+        $stmt = $connection->prepare('SELECT * FROM `technology` WHERE name = :name');
+        $this->storage->exchangeArray([]); //removes the reference to prepared span, including the tracked SpanContext
+        $stmt->bindValue('name', 'PHP');
+        $stmt->executeQuery();
+
+        $execute = $this->storage->offsetGet(0);
+        $this->assertCount(1, $execute->getLinks());
+    }
+
     public function test_query_with_bind_variables(): void
     {
         $connection =  self::createConnection();