Enable usage of metrics with same name but different labels

Signed-off-by: Giuseppe Rota <rota.giuseppe@gmail.com>
PromPHP · Jul 6, 2021 · a82fe69 · a82fe69
1 parent bca39eb
commit a82fe69
Show file tree

Hide file tree

Showing 14 changed files with 403 additions and 246 deletions.
diff --git a/src/Prometheus/CollectorRegistry.php b/src/Prometheus/CollectorRegistry.php
@@ -80,9 +80,9 @@ public function getMetricFamilySamples(): array
      * @return Gauge
      * @throws MetricsRegistrationException
      */
-    public function registerGauge(string $namespace, string $name, string $help, $labels = []): Gauge
+    public function registerGauge(string $namespace, string $name, string $help, array $labels = []): Gauge
     {
-        $metricIdentifier = self::metricIdentifier($namespace, $name);
+        $metricIdentifier = self::metricIdentifier($namespace, $name, $labels);
         if (isset($this->gauges[$metricIdentifier])) {
             throw new MetricsRegistrationException("Metric already registered");
         }
@@ -99,13 +99,14 @@ public function registerGauge(string $namespace, string $name, string $help, $la
     /**
      * @param string $namespace
      * @param string $name
+     * @param string[] $labels
      *
      * @return Gauge
      * @throws MetricNotFoundException
      */
-    public function getGauge(string $namespace, string $name): Gauge
+    public function getGauge(string $namespace, string $name, array $labels = []): Gauge
     {
-        $metricIdentifier = self::metricIdentifier($namespace, $name);
+        $metricIdentifier = self::metricIdentifier($namespace, $name, $labels);
         if (!isset($this->gauges[$metricIdentifier])) {
             throw new MetricNotFoundException("Metric not found:" . $metricIdentifier);
         }
@@ -121,10 +122,10 @@ public function getGauge(string $namespace, string $name): Gauge
      * @return Gauge
      * @throws MetricsRegistrationException
      */
-    public function getOrRegisterGauge(string $namespace, string $name, string $help, $labels = []): Gauge
+    public function getOrRegisterGauge(string $namespace, string $name, string $help, array $labels = []): Gauge
     {
         try {
-            $gauge = $this->getGauge($namespace, $name);
+            $gauge = $this->getGauge($namespace, $name, $labels);
         } catch (MetricNotFoundException $e) {
             $gauge = $this->registerGauge($namespace, $name, $help, $labels);
         }
@@ -140,9 +141,9 @@ public function getOrRegisterGauge(string $namespace, string $name, string $help
      * @return Counter
      * @throws MetricsRegistrationException
      */
-    public function registerCounter(string $namespace, string $name, string $help, $labels = []): Counter
+    public function registerCounter(string $namespace, string $name, string $help, array $labels = []): Counter
     {
-        $metricIdentifier = self::metricIdentifier($namespace, $name);
+        $metricIdentifier = self::metricIdentifier($namespace, $name, $labels);
         if (isset($this->counters[$metricIdentifier])) {
             throw new MetricsRegistrationException("Metric already registered");
         }
@@ -153,23 +154,24 @@ public function registerCounter(string $namespace, string $name, string $help, $
             $help,
             $labels
         );
-        return $this->counters[self::metricIdentifier($namespace, $name)];
+        return $this->counters[$metricIdentifier];
     }
 
     /**
      * @param string $namespace
      * @param string $name
+     * @param string[] $labels
      *
      * @return Counter
      * @throws MetricNotFoundException
      */
-    public function getCounter(string $namespace, string $name): Counter
+    public function getCounter(string $namespace, string $name, array $labels = []): Counter
     {
-        $metricIdentifier = self::metricIdentifier($namespace, $name);
+        $metricIdentifier = self::metricIdentifier($namespace, $name, $labels);
         if (!isset($this->counters[$metricIdentifier])) {
             throw new MetricNotFoundException("Metric not found:" . $metricIdentifier);
         }
-        return $this->counters[self::metricIdentifier($namespace, $name)];
+        return $this->counters[$metricIdentifier];
     }
 
     /**
@@ -181,10 +183,10 @@ public function getCounter(string $namespace, string $name): Counter
      * @return Counter
      * @throws MetricsRegistrationException
      */
-    public function getOrRegisterCounter(string $namespace, string $name, string $help, $labels = []): Counter
+    public function getOrRegisterCounter(string $namespace, string $name, string $help, array $labels = []): Counter
     {
         try {
-            $counter = $this->getCounter($namespace, $name);
+            $counter = $this->getCounter($namespace, $name, $labels);
         } catch (MetricNotFoundException $e) {
             $counter = $this->registerCounter($namespace, $name, $help, $labels);
         }
@@ -208,7 +210,7 @@ public function registerHistogram(
         array $labels = [],
         array $buckets = null
     ): Histogram {
-        $metricIdentifier = self::metricIdentifier($namespace, $name);
+        $metricIdentifier = self::metricIdentifier($namespace, $name, $labels);
         if (isset($this->histograms[$metricIdentifier])) {
             throw new MetricsRegistrationException("Metric already registered");
         }
@@ -226,17 +228,18 @@ public function registerHistogram(
     /**
      * @param string $namespace
      * @param string $name
+     * @param string[] $labels
      *
      * @return Histogram
      * @throws MetricNotFoundException
      */
-    public function getHistogram(string $namespace, string $name): Histogram
+    public function getHistogram(string $namespace, string $name, array $labels = []): Histogram
     {
-        $metricIdentifier = self::metricIdentifier($namespace, $name);
+        $metricIdentifier = self::metricIdentifier($namespace, $name, $labels);
         if (!isset($this->histograms[$metricIdentifier])) {
             throw new MetricNotFoundException("Metric not found:" . $metricIdentifier);
         }
-        return $this->histograms[self::metricIdentifier($namespace, $name)];
+        return $this->histograms[$metricIdentifier];
     }
 
     /**
@@ -257,7 +260,7 @@ public function getOrRegisterHistogram(
         array $buckets = null
     ): Histogram {
         try {
-            $histogram = $this->getHistogram($namespace, $name);
+            $histogram = $this->getHistogram($namespace, $name, $labels);
         } catch (MetricNotFoundException $e) {
             $histogram = $this->registerHistogram($namespace, $name, $help, $labels, $buckets);
         }
@@ -267,12 +270,13 @@ public function getOrRegisterHistogram(
     /**
      * @param string $namespace
      * @param string $name
+     * @param string[] $labels
      *
      * @return string
      */
-    private static function metricIdentifier(string $namespace, string $name): string
+    private static function metricIdentifier(string $namespace, string $name, array $labels = []): string
     {
-        return $namespace . ":" . $name;
+        return $namespace . ":" . $name . ':' . implode('|', $labels);
     }
 
     private function registerDefaultMetrics(): void

diff --git a/src/Prometheus/MetricFamilySamples.php b/src/Prometheus/MetricFamilySamples.php
@@ -39,7 +39,6 @@ public function __construct(array $data)
         $this->name = $data['name'];
         $this->type = $data['type'];
         $this->help = $data['help'];
-        $this->labelNames = $data['labelNames'];
         foreach ($data['samples'] as $sampleData) {
             $this->samples[] = new Sample($sampleData);
         }
@@ -76,20 +75,4 @@ public function getSamples(): array
     {
         return $this->samples;
     }
-
-    /**
-     * @return string[]
-     */
-    public function getLabelNames(): array
-    {
-        return $this->labelNames;
-    }
-
-    /**
-     * @return bool
-     */
-    public function hasLabelNames(): bool
-    {
-        return $this->labelNames !== [];
-    }
 }
diff --git a/src/Prometheus/RenderTextFormat.php b/src/Prometheus/RenderTextFormat.php
@@ -36,9 +36,8 @@ public function render(array $metrics): string
      */
     private function renderSample(MetricFamilySamples $metric, Sample $sample): string
     {
-        $labelNames = $metric->getLabelNames();
-        if ($metric->hasLabelNames() || $sample->hasLabelNames()) {
-            $escapedLabels = $this->escapeAllLabels($labelNames, $sample);
+        if ($sample->hasLabelNames()) {
+            $escapedLabels = $this->escapeAllLabels($sample);
             return $sample->getName() . '{' . implode(',', $escapedLabels) . '} ' . $sample->getValue();
         }
         return $sample->getName() . ' ' . $sample->getValue();
@@ -54,16 +53,15 @@ private function escapeLabelValue(string $v): string
     }
 
     /**
-     * @param string[]  $labelNames
      * @param Sample $sample
      *
      * @return string[]
      */
-    private function escapeAllLabels(array $labelNames, Sample $sample): array
+    private function escapeAllLabels(Sample $sample): array
     {
         $escapedLabels = [];
 
-        $labels = array_combine(array_merge($labelNames, $sample->getLabelNames()), $sample->getLabelValues());
+        $labels = array_combine($sample->getLabelNames(), $sample->getLabelValues());
 
         if ($labels === false) {
             return [];