cleanup

Author: jaydeluca

prometheus-metrics-core/src/main/java/io/prometheus/metrics/core/metrics/Counter.java

@@ -5,6 +5,7 @@
 import io.prometheus.metrics.core.datapoints.CounterDataPoint;
 import io.prometheus.metrics.core.exemplars.ExemplarSampler;
 import io.prometheus.metrics.core.exemplars.ExemplarSamplerConfig;
+import io.prometheus.metrics.model.registry.MetricType;
 import io.prometheus.metrics.model.snapshots.CounterSnapshot;
 import io.prometheus.metrics.model.snapshots.Exemplar;
 import io.prometheus.metrics.model.snapshots.Labels;
@@ -93,8 +94,8 @@ protected CounterSnapshot collect(List<Labels> labels, List<DataPoint> metricDat
   }
 
   @Override
-  public io.prometheus.metrics.model.registry.MetricType getMetricType() {
-    return io.prometheus.metrics.model.registry.MetricType.COUNTER;
+  public MetricType getMetricType() {
+    return MetricType.COUNTER;
   }
 
   @Override

prometheus-metrics-core/src/main/java/io/prometheus/metrics/core/metrics/Gauge.java

@@ -5,6 +5,7 @@
 import io.prometheus.metrics.core.datapoints.GaugeDataPoint;
 import io.prometheus.metrics.core.exemplars.ExemplarSampler;
 import io.prometheus.metrics.core.exemplars.ExemplarSamplerConfig;
+import io.prometheus.metrics.model.registry.MetricType;
 import io.prometheus.metrics.model.snapshots.Exemplar;
 import io.prometheus.metrics.model.snapshots.GaugeSnapshot;
 import io.prometheus.metrics.model.snapshots.Labels;
@@ -95,8 +96,8 @@ protected GaugeSnapshot collect(List<Labels> labels, List<DataPoint> metricData)
   }
 
   @Override
-  public io.prometheus.metrics.model.registry.MetricType getMetricType() {
-    return io.prometheus.metrics.model.registry.MetricType.GAUGE;
+  public MetricType getMetricType() {
+    return MetricType.GAUGE;
   }
 
   @Override

prometheus-metrics-core/src/main/java/io/prometheus/metrics/core/metrics/Histogram.java

@@ -7,6 +7,7 @@
 import io.prometheus.metrics.core.exemplars.ExemplarSampler;
 import io.prometheus.metrics.core.exemplars.ExemplarSamplerConfig;
 import io.prometheus.metrics.core.util.Scheduler;
+import io.prometheus.metrics.model.registry.MetricType;
 import io.prometheus.metrics.model.snapshots.ClassicHistogramBuckets;
 import io.prometheus.metrics.model.snapshots.Exemplars;
 import io.prometheus.metrics.model.snapshots.HistogramSnapshot;
@@ -641,8 +642,8 @@ public HistogramSnapshot collect() {
   }
 
   @Override
-  public io.prometheus.metrics.model.registry.MetricType getMetricType() {
-    return io.prometheus.metrics.model.registry.MetricType.HISTOGRAM;
+  public MetricType getMetricType() {
+    return MetricType.HISTOGRAM;
   }
 
   @Override

prometheus-metrics-core/src/main/java/io/prometheus/metrics/core/metrics/Info.java

@@ -1,6 +1,7 @@
 package io.prometheus.metrics.core.metrics;
 
 import io.prometheus.metrics.config.PrometheusProperties;
+import io.prometheus.metrics.model.registry.MetricType;
 import io.prometheus.metrics.model.snapshots.InfoSnapshot;
 import io.prometheus.metrics.model.snapshots.Labels;
 import io.prometheus.metrics.model.snapshots.Unit;
@@ -106,8 +107,8 @@ public InfoSnapshot collect() {
   }
 
   @Override
-  public io.prometheus.metrics.model.registry.MetricType getMetricType() {
-    return io.prometheus.metrics.model.registry.MetricType.INFO;
+  public MetricType getMetricType() {
+    return MetricType.INFO;
   }
 
   public static Builder builder() {

prometheus-metrics-core/src/main/java/io/prometheus/metrics/core/metrics/StateSet.java

@@ -4,6 +4,7 @@
 
 import io.prometheus.metrics.config.PrometheusProperties;
 import io.prometheus.metrics.core.datapoints.StateSetDataPoint;
+import io.prometheus.metrics.model.registry.MetricType;
 import io.prometheus.metrics.model.snapshots.Labels;
 import io.prometheus.metrics.model.snapshots.StateSetSnapshot;
 import java.util.ArrayList;
@@ -74,8 +75,8 @@ public StateSetSnapshot collect() {
   }
 
   @Override
-  public io.prometheus.metrics.model.registry.MetricType getMetricType() {
-    return io.prometheus.metrics.model.registry.MetricType.STATESET;
+  public MetricType getMetricType() {
+    return MetricType.STATESET;
   }
 
   @Override

prometheus-metrics-core/src/main/java/io/prometheus/metrics/core/metrics/Summary.java

@@ -7,6 +7,7 @@
 import io.prometheus.metrics.core.datapoints.DistributionDataPoint;
 import io.prometheus.metrics.core.exemplars.ExemplarSampler;
 import io.prometheus.metrics.core.exemplars.ExemplarSamplerConfig;
+import io.prometheus.metrics.model.registry.MetricType;
 import io.prometheus.metrics.model.snapshots.Exemplars;
 import io.prometheus.metrics.model.snapshots.Labels;
 import io.prometheus.metrics.model.snapshots.Quantile;
@@ -110,8 +111,8 @@ public SummarySnapshot collect() {
   }
 
   @Override
-  public io.prometheus.metrics.model.registry.MetricType getMetricType() {
-    return io.prometheus.metrics.model.registry.MetricType.SUMMARY;
+  public MetricType getMetricType() {
+    return MetricType.SUMMARY;
   }
 
   @Override

prometheus-metrics-exposition-textformats/src/main/java/io/prometheus/metrics/expositionformats/TextFormatUtil.java

@@ -1,7 +1,19 @@
 package io.prometheus.metrics.expositionformats;
 
 import io.prometheus.metrics.config.EscapingScheme;
-import io.prometheus.metrics.model.snapshots.*;
+import io.prometheus.metrics.model.snapshots.CounterSnapshot;
+import io.prometheus.metrics.model.snapshots.DataPointSnapshot;
+import io.prometheus.metrics.model.snapshots.GaugeSnapshot;
+import io.prometheus.metrics.model.snapshots.HistogramSnapshot;
+import io.prometheus.metrics.model.snapshots.InfoSnapshot;
+import io.prometheus.metrics.model.snapshots.Labels;
+import io.prometheus.metrics.model.snapshots.MetricSnapshot;
+import io.prometheus.metrics.model.snapshots.MetricSnapshots;
+import io.prometheus.metrics.model.snapshots.PrometheusNaming;
+import io.prometheus.metrics.model.snapshots.SnapshotEscaper;
+import io.prometheus.metrics.model.snapshots.StateSetSnapshot;
+import io.prometheus.metrics.model.snapshots.SummarySnapshot;
+import io.prometheus.metrics.model.snapshots.UnknownSnapshot;
 
 import java.io.IOException;
 import java.io.Writer;

prometheus-metrics-model/src/main/java/io/prometheus/metrics/model/registry/PrometheusRegistry.java

@@ -1,5 +1,6 @@
 package io.prometheus.metrics.model.registry;
 
+import io.prometheus.metrics.model.snapshots.DataPointSnapshot;
 import io.prometheus.metrics.model.snapshots.MetricSnapshot;
 import io.prometheus.metrics.model.snapshots.MetricSnapshots;
 import java.util.List;
@@ -30,33 +31,63 @@ public void register(MultiCollector collector) {
 
   /**
    * Validates that the new collector's type is consistent with any existing collectors that have
-   * the same Prometheus name. This prevents registering, for example, a Counter and a Gauge with
-   * the same name.
-   *
-   * <p>Uses O(1) lookup via cached metric identifiers for efficiency.
+   * the same Prometheus name, and that there are no duplicate label sets.
    */
   private void validateTypeConsistency(Collector newCollector) {
     String newName = newCollector.getPrometheusName();
     MetricType newType = newCollector.getMetricType();
 
-    // If name or type is null, skip validation
-    if (newName == null || newType == null) {
+    if (newName == null) {
       return;
     }
 
-    MetricIdentifier newIdentifier = new MetricIdentifier(newName, newType);
-
-    // O(1) lookup in cache
-    MetricIdentifier existing = registeredMetrics.get(newName);
-    if (existing != null && !newIdentifier.isCompatibleWith(existing)) {
-      throw new IllegalArgumentException(
-          "Collector with Prometheus name '"
-              + newName
-              + "' is already registered with type "
-              + existing.getType()
-              + ", but you are trying to register a new collector with type "
-              + newType
-              + ". All collectors with the same Prometheus name must have the same type.");
+    // Validate type consistency if type is provided
+    if (newType != null) {
+      MetricIdentifier newIdentifier = new MetricIdentifier(newName, newType);
+      MetricIdentifier existing = registeredMetrics.get(newName);
+      if (existing != null && !newIdentifier.isCompatibleWith(existing)) {
+        throw new IllegalArgumentException(
+            "Collector with Prometheus name '"
+                + newName
+                + "' is already registered with type "
+                + existing.getType()
+                + ", but you are trying to register a new collector with type "
+                + newType
+                + ". All collectors with the same Prometheus name must have the same type.");
+      }
+    }
+
+    // Validate no duplicate labels by collecting and comparing snapshots
+    MetricSnapshot newSnapshot = newCollector.collect();
+    if (newSnapshot != null) {
+      for (Collector existingCollector : collectors) {
+        if (newName.equals(existingCollector.getPrometheusName())) {
+          MetricSnapshot existingSnapshot = existingCollector.collect();
+          if (existingSnapshot != null) {
+            validateNoDuplicateLabels(newSnapshot, existingSnapshot);
+          }
+        }
+      }
+    }
+  }
+
+  /**
+   * Validates that two snapshots with the same Prometheus name don't have overlapping label sets.
+   */
+  private void validateNoDuplicateLabels(MetricSnapshot snapshot1, MetricSnapshot snapshot2) {
+    String metricName = snapshot1.getMetadata().getName();
+
+    for (DataPointSnapshot dp1 : snapshot1.getDataPoints()) {
+      for (DataPointSnapshot dp2 : snapshot2.getDataPoints()) {
+        if (dp1.getLabels().equals(dp2.getLabels())) {
+          throw new IllegalArgumentException(
+              "Duplicate labels detected for metric '"
+                  + metricName
+                  + "' with labels "
+                  + dp1.getLabels()
+                  + ". Each time series (metric name + label set) must be unique.");
+        }
+      }
     }
   }
 
@@ -65,22 +96,20 @@ private void validateTypeConsistency(Collector newCollector) {
    *
    * <p>Validates each Prometheus name returned by the MultiCollector. If the MultiCollector
    * provides type information via {@link MultiCollector#getMetricType(String)}, validation happens
-   * at registration time. Otherwise, validation is deferred to scrape time.
+   * at registration time.
    */
   private void validateTypeConsistency(MultiCollector newCollector) {
     List<String> names = newCollector.getPrometheusNames();
 
     for (String name : names) {
       MetricType type = newCollector.getMetricType(name);
 
-      // Skip validation if type is unknown
       if (type == null) {
         continue;
       }
 
       MetricIdentifier newIdentifier = new MetricIdentifier(name, type);
 
-      // O(1) lookup in cache
       MetricIdentifier existing = registeredMetrics.get(name);
       if (existing != null && !newIdentifier.isCompatibleWith(existing)) {
         throw new IllegalArgumentException(
@@ -94,13 +123,12 @@ private void validateTypeConsistency(MultiCollector newCollector) {
                 + " the same type.");
       }
 
-      // Cache the identifier for future lookups
       registeredMetrics.putIfAbsent(name, newIdentifier);
     }
   }
 
   /**
-   * Caches the metric identifier for fast O(1) lookup during future registrations.
+   * Caches the metric identifier for lookup during future registrations.
    *
    * <p>Only caches if the collector provides both a Prometheus name and type.
    */
@@ -116,8 +144,7 @@ private void cacheMetricIdentifier(Collector collector) {
   public void unregister(Collector collector) {
     collectors.remove(collector);
     // Note: We don't remove from cache because another collector with the same name might exist
-    // The cache will be cleaned up when clear() is called or can be left as-is (it's just
-    // metadata)
+    // The cache will be cleaned up when clear() is called
   }
 
   public void unregister(MultiCollector collector) {

prometheus-metrics-model/src/main/java/io/prometheus/metrics/model/snapshots/MetricSnapshots.java

@@ -30,67 +30,34 @@ public MetricSnapshots(MetricSnapshot... snapshots) {
    * #builder()}.
    *
    * @param snapshots the constructor creates a sorted copy of snapshots.
-   * @throws IllegalArgumentException if there are duplicate metric names with different types, or
-   *     duplicate label sets within the same metric name
+   * @throws IllegalArgumentException if snapshots with the same Prometheus name have conflicting types
    */
   public MetricSnapshots(Collection<MetricSnapshot> snapshots) {
-    validateSnapshots(snapshots);
+    validateTypeConsistency(snapshots);
     List<MetricSnapshot> list = new ArrayList<>(snapshots);
     list.sort(comparing(s -> s.getMetadata().getPrometheusName()));
     this.snapshots = unmodifiableList(list);
   }
 
   /**
-   * Validates that there are no duplicate time series (same metric name + same label set), and that
-   * all metrics with the same name have the same type.
+   * Validates that all snapshots with the same Prometheus name have the same type.
    */
-  private static void validateSnapshots(Collection<MetricSnapshot> snapshots) {
-    // Group snapshots by Prometheus name
-    Map<String, List<MetricSnapshot>> groupedByName = new HashMap<>();
+  private static void validateTypeConsistency(Collection<MetricSnapshot> snapshots) {
+    Map<String, Class<? extends MetricSnapshot>> typesByName = new HashMap<>();
     for (MetricSnapshot snapshot : snapshots) {
       String prometheusName = snapshot.getMetadata().getPrometheusName();
-      groupedByName.computeIfAbsent(prometheusName, k -> new ArrayList<>()).add(snapshot);
-    }
-
-    // For each group with multiple snapshots, validate type consistency and check for duplicate
-    // labels
-    for (Map.Entry<String, List<MetricSnapshot>> entry : groupedByName.entrySet()) {
-      if (entry.getValue().size() > 1) {
-        String prometheusName = entry.getKey();
-        List<MetricSnapshot> snapshotsWithSameName = entry.getValue();
-
-        // Check that all snapshots with the same name have the same type
-        Class<?> firstType = snapshotsWithSameName.get(0).getClass();
-        for (int i = 1; i < snapshotsWithSameName.size(); i++) {
-          MetricSnapshot snapshot = snapshotsWithSameName.get(i);
-          if (!firstType.equals(snapshot.getClass())) {
-            throw new IllegalArgumentException(
-                "Conflicting metric types for Prometheus name '"
-                    + prometheusName
-                    + "': "
-                    + firstType.getSimpleName()
-                    + " vs "
-                    + snapshot.getClass().getSimpleName()
-                    + ". All metrics with the same Prometheus name must have the same type.");
-          }
-        }
-
-        // Check for duplicate label sets
-        Set<Labels> seenLabels = new HashSet<>();
-        for (MetricSnapshot snapshot : snapshotsWithSameName) {
-          for (DataPointSnapshot dataPoint : snapshot.getDataPoints()) {
-            Labels labels = dataPoint.getLabels();
-            if (!seenLabels.add(labels)) {
-              throw new IllegalArgumentException(
-                  "Duplicate labels detected for metric '"
-                      + prometheusName
-                      + "': "
-                      + labels
-                      + ". Each time series (metric name + label set) must be unique.");
-            }
-          }
-        }
+      Class<? extends MetricSnapshot> existingType = typesByName.get(prometheusName);
+      if (existingType != null && !existingType.equals(snapshot.getClass())) {
+        throw new IllegalArgumentException(
+            "Conflicting metric types for Prometheus name '"
+                + prometheusName
+                + "': "
+                + existingType.getSimpleName()
+                + " vs "
+                + snapshot.getClass().getSimpleName()
+                + ". All metrics with the same Prometheus name must have the same type.");
       }
+      typesByName.put(prometheusName, snapshot.getClass());
     }
   }