Merge pull request #42 from worldia/feat/opentelemetry-meter-interface

feat: implement MeterInterface from OpenTelemetry

src/Metrics/CounterAdapter.php

@@ -0,0 +1,41 @@
+<?php
+
+/*
+ * This file is part of the worldia/instrumentation-bundle package.
+ * (c) Worldia <developers@worldia.com>
+ */
+
+namespace Instrumentation\Metrics;
+
+use OpenTelemetry\API\Metrics\CounterInterface;
+use Prometheus\CollectorRegistry;
+
+class CounterAdapter implements CounterInterface
+{
+    public function __construct(
+        private string $name,
+        private string $description,
+        private CollectorRegistry $collectorRegistry,
+    ) {
+    }
+
+    /**
+     * @param int                                $amount
+     * @param array{labels: array<string,mixed>} $attributes
+     */
+    public function add($amount, iterable $attributes = [], $context = null): void
+    {
+        /** @var array<string> $labelNames */
+        $labelNames = array_keys($attributes['labels'] ?? []);
+        $labelValues = array_values($attributes['labels'] ?? []);
+
+        $counter = $this->collectorRegistry->getOrRegisterCounter(
+            '',
+            $this->name,
+            $this->description,
+            $labelNames,
+        );
+
+        $counter->incBy($amount, $labelValues);
+    }
+}

src/Metrics/HistogramAdapter.php

@@ -0,0 +1,41 @@
+<?php
+
+/*
+ * This file is part of the worldia/instrumentation-bundle package.
+ * (c) Worldia <developers@worldia.com>
+ */
+
+namespace Instrumentation\Metrics;
+
+use OpenTelemetry\API\Metrics\HistogramInterface;
+use Prometheus\CollectorRegistry;
+use Prometheus\Histogram;
+
+class HistogramAdapter implements HistogramInterface
+{
+    public function __construct(
+        private string $name,
+        private string $description,
+        private CollectorRegistry $collectorRegistry,
+    ) {
+    }
+
+    /**
+     * @param array{labels: array<string,mixed>, buckets?: array<int>} $attributes
+     */
+    public function record($amount, iterable $attributes = [], $context = null): void
+    {
+        /** @var array<string> $labelNames */
+        $labelNames = array_keys($attributes['labels'] ?? []);
+        $labelValues = array_values($attributes['labels'] ?? []);
+
+        $histogram = $this->collectorRegistry->getOrRegisterHistogram(
+            '',
+            $this->name,
+            $this->description,
+            $labelNames,
+            $attributes['buckets'] ?? Histogram::getDefaultBuckets(),
+        );
+        $histogram->observe($amount, $labelValues);
+    }
+}

src/Metrics/Meter.php

@@ -0,0 +1,55 @@
+<?php
+
+/*
+ * This file is part of the worldia/instrumentation-bundle package.
+ * (c) Worldia <developers@worldia.com>
+ */
+
+namespace Instrumentation\Metrics;
+
+use OpenTelemetry\API\Metrics\CounterInterface;
+use OpenTelemetry\API\Metrics\HistogramInterface;
+use OpenTelemetry\API\Metrics\MeterInterface;
+use OpenTelemetry\API\Metrics\ObservableCounterInterface;
+use OpenTelemetry\API\Metrics\ObservableGaugeInterface;
+use OpenTelemetry\API\Metrics\ObservableUpDownCounterInterface;
+use OpenTelemetry\API\Metrics\UpDownCounterInterface;
+use Prometheus\CollectorRegistry;
+
+class Meter implements MeterInterface
+{
+    public function __construct(
+        private CollectorRegistry $collectorRegistry,
+    ) {
+    }
+
+    public function createCounter(string $name, string $unit = null, string $description = null): CounterInterface
+    {
+        return new CounterAdapter($name, $description ?: '', $this->collectorRegistry);
+    }
+
+    public function createObservableCounter(string $name, string $unit = null, string $description = null, callable ...$callbacks): ObservableCounterInterface
+    {
+        throw new \LogicException(sprintf('Method %s is not implemented', __METHOD__));
+    }
+
+    public function createHistogram(string $name, string $unit = null, string $description = null): HistogramInterface
+    {
+        return new HistogramAdapter($name, $description ?: '', $this->collectorRegistry);
+    }
+
+    public function createObservableGauge(string $name, string $unit = null, string $description = null, callable ...$callbacks): ObservableGaugeInterface
+    {
+        throw new \LogicException(sprintf('Method %s is not implemented', __METHOD__));
+    }
+
+    public function createUpDownCounter(string $name, string $unit = null, string $description = null): UpDownCounterInterface
+    {
+        return new UpDownCounterAdapter($name, $description ?: '', $this->collectorRegistry);
+    }
+
+    public function createObservableUpDownCounter(string $name, string $unit = null, string $description = null, callable ...$callbacks): ObservableUpDownCounterInterface
+    {
+        throw new \LogicException(sprintf('Method %s is not implemented', __METHOD__));
+    }
+}

src/Metrics/UpDownCounterAdapter.php

@@ -0,0 +1,45 @@
+<?php
+
+/*
+ * This file is part of the worldia/instrumentation-bundle package.
+ * (c) Worldia <developers@worldia.com>
+ */
+
+namespace Instrumentation\Metrics;
+
+use OpenTelemetry\API\Metrics\UpDownCounterInterface;
+use Prometheus\CollectorRegistry;
+
+class UpDownCounterAdapter implements UpDownCounterInterface
+{
+    public function __construct(
+        private string $name,
+        private string $description,
+        private CollectorRegistry $collectorRegistry,
+    ) {
+    }
+
+    /**
+     * @param int                                $amount
+     * @param array{labels: array<string,mixed>} $attributes
+     */
+    public function add($amount, iterable $attributes = [], $context = null): void
+    {
+        /** @var array<string> $labelNames */
+        $labelNames = array_keys($attributes['labels'] ?? []);
+        $labelValues = array_values($attributes['labels'] ?? []);
+
+        $gauge = $this->collectorRegistry->getOrRegisterGauge(
+            '',
+            $this->name,
+            $this->description,
+            $labelNames,
+        );
+
+        if ($amount > 0) {
+            $gauge->incBy($amount, $labelValues);
+        } else {
+            $gauge->decBy(abs($amount), $labelValues);
+        }
+    }
+}