1 files changed, 61 insertions, 0 deletions
diff --git a/vendor/open-telemetry/sdk/Metrics/ObservableInstrumentTrait.php b/vendor/open-telemetry/sdk/Metrics/ObservableInstrumentTrait.php
new file mode 100644
index 000000000..b7fdcf5f8
--- /dev/null
+++ b/vendor/open-telemetry/sdk/Metrics/ObservableInstrumentTrait.php
@@ -0,0 +1,61 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenTelemetry\SDK\Metrics;
+
+use ArrayAccess;
+use OpenTelemetry\API\Metrics\ObservableCallbackInterface;
+use OpenTelemetry\API\Metrics\ObserverInterface;
+use function OpenTelemetry\SDK\Common\Util\closure;
+use function OpenTelemetry\SDK\Common\Util\weaken;
+use OpenTelemetry\SDK\Metrics\MetricRegistry\MetricWriterInterface;
+
+/**
+ * @internal
+ */
+trait ObservableInstrumentTrait
+{
+    private MetricWriterInterface $writer;
+    private Instrument $instrument;
+    private ReferenceCounterInterface $referenceCounter;
+    private ArrayAccess $destructors;
+
+    public function __construct(
+        MetricWriterInterface $writer,
+        Instrument $instrument,
+        ReferenceCounterInterface $referenceCounter,
+        ArrayAccess $destructors
+    ) {
+        $this->writer = $writer;
+        $this->instrument = $instrument;
+        $this->referenceCounter = $referenceCounter;
+        $this->destructors = $destructors;
+
+        $this->referenceCounter->acquire();
+    }
+
+    public function __destruct()
+    {
+        $this->referenceCounter->release();
+    }
+
+    /**
+     * @param callable(ObserverInterface): void $callback
+     */
+    public function observe(callable $callback): ObservableCallbackInterface
+    {
+        $callback = weaken(closure($callback), $target);
+
+        $callbackId = $this->writer->registerCallback($callback, $this->instrument);
+        $this->referenceCounter->acquire();
+
+        $destructor = null;
+        if ($target) {
+            $destructor = $this->destructors[$target] ??= new ObservableCallbackDestructor($this->writer, $this->referenceCounter);
+            $destructor->callbackIds[$callbackId] = $callbackId;
+        }
+
+        return new ObservableCallback($this->writer, $this->referenceCounter, $callbackId, $destructor, $target);
+    }
+}