test: validate Micrometer opt-in compatibility

.github/renovate.json5

@@ -38,6 +38,21 @@
       groupName: "protobuf",
       separateMajorMinor: false,
     },
+    {
+      "description": "Flint autofix: align extractVersion for protoc",
+      "extractVersion": "^(?<version>.+)\\.0\\.0$",
+      "matchDepNames": [
+        "protoc"
+      ]
+    }
+  ],
+  customManagers: [
+    {
+      customType: "regex",
+      managerFilePatterns: ["/^\\.github\\/workflows\\/micrometer-compatibility\\.yml$/"],
+      matchStrings: [
+        "# renovate: datasource=(?<datasource>\\S+) depName=(?<depName>\\S+) packageName=(?<packageName>\\S+) currentValue=(?<currentValue>\\S+)\\n\\s*DEFAULT_MICROMETER_REF:\\s*(?<currentDigest>[a-f0-9]{40})",
+      ],
+    },
   ],
-  customManagers: [],
-}
+}

.github/workflows/micrometer-compatibility.yml

@@ -1,5 +1,5 @@
 ---
-name: Micrometer Compatibility
+name: Micrometer Opt-In Compatibility
 
 on:
   pull_request:
@@ -8,14 +8,19 @@ on:
       micrometer-repository:
         description: Micrometer repository to test, in owner/name form
         required: false
-        default: micrometer-metrics/micrometer
+        default: zeitlinger/micrometer
       micrometer-ref:
         description: Micrometer branch, tag, or commit to test
         required: false
-        default: main
+        default: 1af1b3185058941eea57dc467bfe0df5a4786fe4
 
 permissions: {}
 
+env:
+  DEFAULT_MICROMETER_REPOSITORY: zeitlinger/micrometer
+  # renovate: datasource=git-refs depName=zeitlinger/micrometer packageName=https://github.com/zeitlinger/micrometer currentValue=feat/prometheus-client-opt-in
+  DEFAULT_MICROMETER_REF: 1af1b3185058941eea57dc467bfe0df5a4786fe4
+
 jobs:
   micrometer-compatibility:
     runs-on: ubuntu-24.04
@@ -34,6 +39,6 @@ jobs:
           key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}
       - name: Run Micrometer compatibility tests
         env:
-          MICROMETER_REPOSITORY: ${{ github.event_name == 'workflow_dispatch' && github.event.inputs.micrometer-repository || 'micrometer-metrics/micrometer' }}
-          MICROMETER_REF: ${{ github.event_name == 'workflow_dispatch' && github.event.inputs.micrometer-ref || 'main' }}
+          MICROMETER_REPOSITORY: ${{ github.event_name == 'workflow_dispatch' && github.event.inputs.micrometer-repository || env.DEFAULT_MICROMETER_REPOSITORY }}
+          MICROMETER_REF: ${{ github.event_name == 'workflow_dispatch' && github.event.inputs.micrometer-ref || env.DEFAULT_MICROMETER_REF }}
         run: mise run micrometer:test

.mise/lib/micrometer_compat.py

@@ -13,10 +13,12 @@
     os.environ.get("MICROMETER_DIR", "/tmp/micrometer-compat")
 )
 DEFAULT_MICROMETER_REPOSITORY = os.environ.get(
-    "MICROMETER_REPOSITORY", "micrometer-metrics/micrometer"
+    "MICROMETER_REPOSITORY", "zeitlinger/micrometer"
 )
 DEFAULT_MICROMETER_REMOTE = os.environ.get("MICROMETER_REMOTE", "origin")
-DEFAULT_MICROMETER_REF = os.environ.get("MICROMETER_REF", "main")
+DEFAULT_MICROMETER_REF = os.environ.get(
+    "MICROMETER_REF", "feat/prometheus-client-opt-in"
+)
 DEFAULT_INIT_SCRIPT = Path(
     os.environ.get("MICROMETER_INIT_SCRIPT", "/tmp/micrometer-prom-local.init.gradle")
 )

examples/example-exporter-multi-target/src/main/java/io/prometheus/metrics/examples/multitarget/SampleMultiCollector.java

@@ -77,7 +77,12 @@ protected MetricSnapshots collectMetricSnapshots(PrometheusScrapeRequest scrapeR
     return new MetricSnapshots(snaps);
   }
 
+  /**
+   * @deprecated Use {@code getMetricFamilyDescriptors()} instead.
+   */
   @Override
+  @Deprecated
+  @SuppressWarnings("InlineMeSuggester")
   public List<String> getPrometheusNames() {
     List<String> names = new ArrayList<String>();
     names.add("x_calls_total");

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

@@ -90,10 +90,15 @@ protected CounterSnapshot collect(List<Labels> labels, List<DataPoint> metricDat
     for (int i = 0; i < labels.size(); i++) {
       data.add(metricData.get(i).collect(labels.get(i)));
     }
-    return new CounterSnapshot(getMetadata(), data);
+    return new CounterSnapshot(metadata, data);
   }
 
+  /**
+   * @deprecated Use {@link #getMetricFamilyDescriptor()} instead.
+   */
   @Override
+  @Deprecated
+  @SuppressWarnings("InlineMeSuggester")
   public MetricType getMetricType() {
     return MetricType.COUNTER;
   }

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

@@ -48,10 +48,15 @@ public CounterSnapshot collect() {
               new CounterSnapshot.CounterDataPointSnapshot(
                   value, makeLabels(labelValues), null, 0L));
         });
-    return new CounterSnapshot(getMetadata(), dataPoints);
+    return new CounterSnapshot(metadata, dataPoints);
   }
 
+  /**
+   * @deprecated Use {@link #getMetricFamilyDescriptor()} instead.
+   */
   @Override
+  @Deprecated
+  @SuppressWarnings("InlineMeSuggester")
   public MetricType getMetricType() {
     return MetricType.COUNTER;
   }

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

@@ -92,10 +92,15 @@ protected GaugeSnapshot collect(List<Labels> labels, List<DataPoint> metricData)
     for (int i = 0; i < labels.size(); i++) {
       dataPointSnapshots.add(metricData.get(i).collect(labels.get(i)));
     }
-    return new GaugeSnapshot(getMetadata(), dataPointSnapshots);
+    return new GaugeSnapshot(metadata, dataPointSnapshots);
   }
 
+  /**
+   * @deprecated Use {@link #getMetricFamilyDescriptor()} instead.
+   */
   @Override
+  @Deprecated
+  @SuppressWarnings("InlineMeSuggester")
   public MetricType getMetricType() {
     return MetricType.GAUGE;
   }

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

@@ -52,10 +52,15 @@ public GaugeSnapshot collect() {
           dataPoints.add(
               new GaugeSnapshot.GaugeDataPointSnapshot(value, makeLabels(labelValues), null, 0L));
         });
-    return new GaugeSnapshot(getMetadata(), dataPoints);
+    return new GaugeSnapshot(metadata, dataPoints);
   }
 
+  /**
+   * @deprecated Use {@link #getMetricFamilyDescriptor()} instead.
+   */
   @Override
+  @Deprecated
+  @SuppressWarnings("InlineMeSuggester")
   public MetricType getMetricType() {
     return MetricType.GAUGE;
   }

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

@@ -647,10 +647,15 @@ protected HistogramSnapshot collect(List<Labels> labels, List<DataPoint> metricD
     for (int i = 0; i < labels.size(); i++) {
       data.add(metricData.get(i).collect(labels.get(i)));
     }
-    return new HistogramSnapshot(getMetadata(), data);
+    return new HistogramSnapshot(metadata, data);
   }
 
+  /**
+   * @deprecated Use {@link #getMetricFamilyDescriptor()} instead.
+   */
   @Override
+  @Deprecated
+  @SuppressWarnings("InlineMeSuggester")
   public MetricType getMetricType() {
     return MetricType.HISTOGRAM;
   }

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

@@ -48,7 +48,7 @@ public void setLabelValues(String... labelValues) {
       throw new IllegalArgumentException(
           getClass().getSimpleName()
               + " "
-              + getMetadata().getName()
+              + metadata.getName()
               + " was created with "
               + labelNames.length
               + " label names, but you called setLabelValues() with "
@@ -66,7 +66,7 @@ public void addLabelValues(String... labelValues) {
       throw new IllegalArgumentException(
           getClass().getSimpleName()
               + " "
-              + getMetadata().getName()
+              + metadata.getName()
               + " was created with "
               + labelNames.length
               + " label names, but you called addLabelValues() with "
@@ -82,7 +82,7 @@ public void remove(String... labelValues) {
       throw new IllegalArgumentException(
           getClass().getSimpleName()
               + " "
-              + getMetadata().getName()
+              + metadata.getName()
               + " was created with "
               + labelNames.length
               + " label names, but you called remove() with "
@@ -103,10 +103,15 @@ public InfoSnapshot collect() {
         data.add(new InfoSnapshot.InfoDataPointSnapshot(label.merge(constLabels)));
       }
     }
-    return new InfoSnapshot(getMetadata(), data);
+    return new InfoSnapshot(metadata, data);
   }
 
+  /**
+   * @deprecated Use {@link #getMetricFamilyDescriptor()} instead.
+   */
   @Override
+  @Deprecated
+  @SuppressWarnings("InlineMeSuggester")
   public MetricType getMetricType() {
     return MetricType.INFO;
   }

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

@@ -1,8 +1,10 @@
 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.Label;
 import io.prometheus.metrics.model.snapshots.Labels;
+import io.prometheus.metrics.model.snapshots.MetricFamilyDescriptor;
 import io.prometheus.metrics.model.snapshots.MetricMetadata;
 import io.prometheus.metrics.model.snapshots.PrometheusNaming;
 import io.prometheus.metrics.model.snapshots.Unit;
@@ -20,7 +22,7 @@
  */
 public abstract class MetricWithFixedMetadata extends Metric {
 
-  private final MetricMetadata metadata;
+  protected final MetricMetadata metadata;
   protected final String[] labelNames;
 
   protected MetricWithFixedMetadata(Builder<?, ?> builder) {
@@ -37,6 +39,22 @@ protected MetricWithFixedMetadata(Builder<?, ?> builder) {
   }
 
   @Override
+  @Nullable
+  @SuppressWarnings("deprecation")
+  public MetricFamilyDescriptor getMetricFamilyDescriptor() {
+    MetricType metricType = getMetricType();
+    if (metricType == null) {
+      return null;
+    }
+    return MetricFamilyDescriptor.of(metricType, metadata, getPrometheusLabels());
+  }
+
+  /**
+   * @deprecated Use {@link #getMetricFamilyDescriptor()} instead.
+   */
+  @Override
+  @Deprecated
+  @SuppressWarnings("InlineMeSuggester")
   public MetricMetadata getMetadata() {
     return metadata;
   }
@@ -65,13 +83,27 @@ private String makeExpositionBaseName(@Nullable String expositionBaseName, @Null
     return expositionBaseName;
   }
 
+  /**
+   * @deprecated Use {@link #getMetricFamilyDescriptor()} instead.
+   */
   @Override
+  @Deprecated
+  @SuppressWarnings("InlineMeSuggester")
   public String getPrometheusName() {
     return metadata.getPrometheusName();
   }
 
+  /**
+   * @deprecated Use {@link #getMetricFamilyDescriptor()} instead.
+   */
   @Override
+  @Deprecated
+  @SuppressWarnings("InlineMeSuggester")
   public Set<String> getLabelNames() {
+    return getPrometheusLabels();
+  }
+
+  private Set<String> getPrometheusLabels() {
     Set<String> names = new HashSet<>();
     for (String labelName : labelNames) {
       names.add(PrometheusNaming.prometheusName(labelName));

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

@@ -60,7 +60,7 @@ private StateSet(Builder builder, String[] names) {
     super(builder);
     this.names = names;
     for (String name : names) {
-      if (this.getMetadata().getPrometheusName().equals(prometheusName(name))) {
+      if (metadata.getPrometheusName().equals(prometheusName(name))) {
         throw new IllegalArgumentException(
             "Label name "
                 + name
@@ -82,10 +82,15 @@ protected StateSetSnapshot collect(List<Labels> labels, List<DataPoint> metricDa
           new StateSetSnapshot.StateSetDataPointSnapshot(
               names, metricDataList.get(i).values, labels.get(i)));
     }
-    return new StateSetSnapshot(getMetadata(), data);
+    return new StateSetSnapshot(metadata, data);
   }
 
+  /**
+   * @deprecated Use {@link #getMetricFamilyDescriptor()} instead.
+   */
   @Override
+  @Deprecated
+  @SuppressWarnings("InlineMeSuggester")
   public MetricType getMetricType() {
     return MetricType.STATESET;
   }

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

@@ -105,7 +105,7 @@ public D labelValues(String... labelValues) {
         throw new IllegalArgumentException(
             getClass().getSimpleName()
                 + " "
-                + getMetadata().getName()
+                + metadata.getName()
                 + " was created with label names, so you must call labelValues(...)"
                 + " when using it.");
       } else {
@@ -120,7 +120,7 @@ public D labelValues(String... labelValues) {
             if (l.get(i) == null) {
               throw new IllegalArgumentException(
                   "null label value for metric "
-                      + getMetadata().getName()
+                      + metadata.getName()
                       + " and label "
                       + labelNames[i]);
             }
@@ -171,7 +171,7 @@ protected MetricsProperties[] getMetricProperties(
     if (Objects.equals(builder.exemplarsEnabled, false)) {
       properties.add(MetricsProperties.builder().exemplarsEnabled(false).build());
     }
-    String metricName = getMetadata().getName();
+    String metricName = metadata.getName();
     if (prometheusProperties.getMetricProperties(metricName) != null) {
       properties.add(prometheusProperties.getMetricProperties(metricName));
     }

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

@@ -116,10 +116,15 @@ protected SummarySnapshot collect(List<Labels> labels, List<DataPoint> metricDat
     for (int i = 0; i < labels.size(); i++) {
       data.add(metricData.get(i).collect(labels.get(i)));
     }
-    return new SummarySnapshot(getMetadata(), data);
+    return new SummarySnapshot(metadata, data);
   }
 
+  /**
+   * @deprecated Use {@link #getMetricFamilyDescriptor()} instead.
+   */
   @Override
+  @Deprecated
+  @SuppressWarnings("InlineMeSuggester")
   public MetricType getMetricType() {
     return MetricType.SUMMARY;
   }

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

@@ -61,10 +61,15 @@ public SummarySnapshot collect() {
               new SummarySnapshot.SummaryDataPointSnapshot(
                   count, sum, quantiles, makeLabels(labelValues), Exemplars.EMPTY, 0L));
         });
-    return new SummarySnapshot(getMetadata(), dataPoints);
+    return new SummarySnapshot(metadata, dataPoints);
   }
 
+  /**
+   * @deprecated Use {@link #getMetricFamilyDescriptor()} instead.
+   */
   @Override
+  @Deprecated
+  @SuppressWarnings("InlineMeSuggester")
   public MetricType getMetricType() {
     return MetricType.SUMMARY;
   }