Merge branch 'main' into lock-free-gauge-set

Author: LKaemmerling

src/Prometheus/RenderTextFormat.php

@@ -40,7 +40,7 @@ private function renderSample(MetricFamilySamples $metric, Sample $sample): stri
     {
         $labelNames = $metric->getLabelNames();
         if ($metric->hasLabelNames() || $sample->hasLabelNames()) {
-            $escapedLabels = $this->escapeAllLabels($labelNames, $sample);
+            $escapedLabels = $this->escapeAllLabels($metric, $labelNames, $sample);
             return $sample->getName() . '{' . implode(',', $escapedLabels) . '} ' . $sample->getValue();
         }
         return $sample->getName() . ' ' . $sample->getValue();
@@ -56,19 +56,20 @@ private function escapeLabelValue(string $v): string
     }
 
     /**
+     * @param MetricFamilySamples $metric
      * @param string[] $labelNames
      * @param Sample $sample
      *
      * @return string[]
      */
-    private function escapeAllLabels(array $labelNames, Sample $sample): array
+    private function escapeAllLabels(MetricFamilySamples $metric, array $labelNames, Sample $sample): array
     {
         $escapedLabels = [];
 
         $labels = array_combine(array_merge($labelNames, $sample->getLabelNames()), $sample->getLabelValues());
 
         if ($labels === false) {
-            throw new RuntimeException('Unable to combine labels.');
+            throw new RuntimeException('Unable to combine labels for metric named ' . $metric->getName());
         }
 
         foreach ($labels as $labelName => $labelValue) {

src/Prometheus/Storage/Redis.php

@@ -226,10 +226,17 @@ private function connectToServer(): void
                 $connection_successful = $this->redis->connect($this->options['host'], (int) $this->options['port'], (float) $this->options['timeout']);
             }
             if (!$connection_successful) {
-                throw new StorageException("Can't connect to Redis server", 0);
+                throw new StorageException(
+                    sprintf("Can't connect to Redis server. %s", $this->redis->getLastError()),
+                    0
+                );
             }
         } catch (\RedisException $e) {
-            throw new StorageException("Can't connect to Redis server", 0, $e);
+            throw new StorageException(
+                sprintf("Can't connect to Redis server. %s", $e->getMessage()),
+                $e->getCode(),
+                $e
+            );
         }
     }