Prom exporter update

exporters/prometheus/src/main/java/io/opentelemetry/exporter/prometheus/Otel2PrometheusConverter.java

@@ -80,6 +80,8 @@ final class Otel2PrometheusConverter {
   private static final long NANOS_PER_MILLISECOND = TimeUnit.MILLISECONDS.toNanos(1);
   static final int MAX_CACHE_SIZE = 10;
 
+  private final boolean otelScopeLabelsEnabled;
+  private final boolean otelTargetInfoMetricEnabled;
   @Nullable private final Predicate<String> allowedResourceAttributesFilter;
 
   /**
@@ -89,12 +91,20 @@ final class Otel2PrometheusConverter {
   private final Map<Attributes, List<AttributeKey<?>>> resourceAttributesToAllowedKeysCache;
 
   /**
-   * Constructor with feature flag parameter.
+   * Constructor with feature flag parameters.
    *
+   * @param otelScopeLabelsEnabled whether to add OpenTelemetry scope labels to exported metrics
+   * @param otelTargetInfoMetricEnabled whether to export the target_info metric with resource
+   *     attributes
    * @param allowedResourceAttributesFilter if not {@code null}, resource attributes with keys
    *     matching this predicate will be added as labels on each exported metric
    */
-  Otel2PrometheusConverter(@Nullable Predicate<String> allowedResourceAttributesFilter) {
+  Otel2PrometheusConverter(
+      boolean otelScopeLabelsEnabled,
+      boolean otelTargetInfoMetricEnabled,
+      @Nullable Predicate<String> allowedResourceAttributesFilter) {
+    this.otelScopeLabelsEnabled = otelScopeLabelsEnabled;
+    this.otelTargetInfoMetricEnabled = otelTargetInfoMetricEnabled;
     this.allowedResourceAttributesFilter = allowedResourceAttributesFilter;
     this.resourceAttributesToAllowedKeysCache =
         allowedResourceAttributesFilter != null
@@ -118,7 +128,7 @@ MetricSnapshots convert(@Nullable Collection<MetricData> metricDataCollection) {
         resource = metricData.getResource();
       }
     }
-    if (resource != null) {
+    if (resource != null && otelTargetInfoMetricEnabled) {
       putOrMerge(snapshotsByName, makeTargetInfo(resource));
     }
     return new MetricSnapshots(snapshotsByName.values());
@@ -457,7 +467,7 @@ private Labels convertAttributes(
           requireNonNull(additionalAttributes[i]), additionalAttributes[i + 1]);
     }
 
-    if (scope != null) {
+    if (scope != null && otelScopeLabelsEnabled) {
       labelNameToValue.putIfAbsent(OTEL_SCOPE_NAME, scope.getName());
       if (scope.getVersion() != null) {
         labelNameToValue.putIfAbsent(OTEL_SCOPE_VERSION, scope.getVersion());

exporters/prometheus/src/main/java/io/opentelemetry/exporter/prometheus/PrometheusHttpServer.java

@@ -42,6 +42,8 @@ public final class PrometheusHttpServer implements MetricReader {
 
   private final String host;
   private final int port;
+  private final boolean otelScopeLabelsEnabled;
+  private final boolean otelTargetInfoMetricEnabled;
   @Nullable private final Predicate<String> allowedResourceAttributesFilter;
   private final MemoryMode memoryMode;
   private final DefaultAggregationSelector defaultAggregationSelector;
@@ -71,18 +73,27 @@ public static PrometheusHttpServerBuilder builder() {
       int port,
       @Nullable ExecutorService executor,
       PrometheusRegistry prometheusRegistry,
+      boolean otelScopeLabelsEnabled,
+      boolean otelTargetInfoMetricEnabled,
       @Nullable Predicate<String> allowedResourceAttributesFilter,
       MemoryMode memoryMode,
       @Nullable HttpHandler defaultHandler,
       DefaultAggregationSelector defaultAggregationSelector,
       @Nullable Authenticator authenticator) {
     this.host = host;
     this.port = port;
+    this.otelScopeLabelsEnabled = otelScopeLabelsEnabled;
+    this.otelTargetInfoMetricEnabled = otelTargetInfoMetricEnabled;
     this.allowedResourceAttributesFilter = allowedResourceAttributesFilter;
     this.memoryMode = memoryMode;
     this.defaultAggregationSelector = defaultAggregationSelector;
     this.builder = builder;
-    this.prometheusMetricReader = new PrometheusMetricReader(allowedResourceAttributesFilter);
+    this.prometheusMetricReader =
+        PrometheusMetricReader.builder()
+            .setOtelScopeLabelsEnabled(otelScopeLabelsEnabled)
+            .setOtelTargetInfoMetricEnabled(otelTargetInfoMetricEnabled)
+            .setAllowedResourceAttributesFilter(allowedResourceAttributesFilter)
+            .build();
     this.prometheusRegistry = prometheusRegistry;
     prometheusRegistry.register(prometheusMetricReader);
     // When memory mode is REUSABLE_DATA, concurrent reads lead to data corruption. To prevent this,
@@ -167,6 +178,8 @@ public String toString() {
     StringJoiner joiner = new StringJoiner(",", "PrometheusHttpServer{", "}");
     joiner.add("host=" + host);
     joiner.add("port=" + port);
+    joiner.add("otelScopeLabelsEnabled=" + otelScopeLabelsEnabled);
+    joiner.add("otelTargetInfoMetricEnabled=" + otelTargetInfoMetricEnabled);
     joiner.add("allowedResourceAttributesFilter=" + allowedResourceAttributesFilter);
     joiner.add("memoryMode=" + memoryMode);
     joiner.add(

exporters/prometheus/src/main/java/io/opentelemetry/exporter/prometheus/PrometheusHttpServerBuilder.java

@@ -30,6 +30,8 @@ public final class PrometheusHttpServerBuilder {
   private String host = DEFAULT_HOST;
   private int port = DEFAULT_PORT;
   private PrometheusRegistry prometheusRegistry = new PrometheusRegistry();
+  private boolean otelScopeLabelsEnabled = true;
+  private boolean otelTargetInfoMetricEnabled = true;
   @Nullable private Predicate<String> allowedResourceAttributesFilter;
   @Nullable private ExecutorService executor;
   private MemoryMode memoryMode = DEFAULT_MEMORY_MODE;
@@ -44,6 +46,8 @@ public final class PrometheusHttpServerBuilder {
     this.host = builder.host;
     this.port = builder.port;
     this.prometheusRegistry = builder.prometheusRegistry;
+    this.otelScopeLabelsEnabled = builder.otelScopeLabelsEnabled;
+    this.otelTargetInfoMetricEnabled = builder.otelTargetInfoMetricEnabled;
     this.allowedResourceAttributesFilter = builder.allowedResourceAttributesFilter;
     this.executor = builder.executor;
     this.memoryMode = builder.memoryMode;
@@ -81,14 +85,18 @@ public PrometheusHttpServerBuilder setPrometheusRegistry(PrometheusRegistry prom
     return this;
   }
 
-  /**
-   * Set if the {@code otel_scope_*} attributes are generated. Default is {@code true}.
-   *
-   * @deprecated {@code otel_scope_*} attributes are always generated.
-   */
+  /** Set if the {@code otel_scope_*} attributes are generated. Default is {@code true}. */
+  @SuppressWarnings("UnusedReturnValue")
+  public PrometheusHttpServerBuilder setOtelScopeLabelsEnabled(boolean otelScopeLabelsEnabled) {
+    this.otelScopeLabelsEnabled = otelScopeLabelsEnabled;
+    return this;
+  }
+
+  /** Set if the {@code otel_target_info} metric is generated. Default is {@code true}. */
   @SuppressWarnings("UnusedReturnValue")
-  @Deprecated
-  public PrometheusHttpServerBuilder setOtelScopeEnabled(boolean otelScopeEnabled) {
+  public PrometheusHttpServerBuilder setOtelTargetInfoMetricEnabled(
+      boolean otelTargetInfoMetricEnabled) {
+    this.otelTargetInfoMetricEnabled = otelTargetInfoMetricEnabled;
     return this;
   }
 
@@ -178,6 +186,8 @@ public PrometheusHttpServer build() {
         port,
         executor,
         prometheusRegistry,
+        otelScopeLabelsEnabled,
+        otelTargetInfoMetricEnabled,
         allowedResourceAttributesFilter,
         memoryMode,
         defaultHandler,

exporters/prometheus/src/main/java/io/opentelemetry/exporter/prometheus/PrometheusMetricReader.java

@@ -28,21 +28,54 @@ public class PrometheusMetricReader implements MetricReader, MultiCollector {
   private volatile CollectionRegistration collectionRegistration = CollectionRegistration.noop();
   private final Otel2PrometheusConverter converter;
 
+  /** Returns a new {@link PrometheusMetricReader} with default configuration. */
+  public static PrometheusMetricReader create() {
+    return builder().build();
+  }
+
+  /** Returns a new {@link PrometheusMetricReaderBuilder}. */
+  public static PrometheusMetricReaderBuilder builder() {
+    return new PrometheusMetricReaderBuilder();
+  }
+
   /**
-   * Deprecated. Use {@link #PrometheusMetricReader(Predicate)}.
+   * Deprecated. Use {@link #builder()}.
    *
-   * @deprecated use {@link #PrometheusMetricReader(Predicate)}.
+   * @deprecated use {@link #builder()}.
    */
   @Deprecated
   @SuppressWarnings({"unused", "InconsistentOverloads"})
   public PrometheusMetricReader(
       boolean otelScopeEnabled, @Nullable Predicate<String> allowedResourceAttributesFilter) {
-    this.converter = new Otel2PrometheusConverter(allowedResourceAttributesFilter);
+    // otelScopeEnabled parameter was used to control the scope info metric, not scope labels.
+    this(
+        allowedResourceAttributesFilter,
+        /* otelScopeLabelsEnabled= */ true,
+        /* otelTargetInfoMetricEnabled= */ true);
   }
 
-  // TODO: refactor to public static create or builder pattern to align with project style
+  /**
+   * Deprecated. Use {@link #builder()}.
+   *
+   * @deprecated use {@link #builder()}.
+   */
+  @Deprecated
   public PrometheusMetricReader(@Nullable Predicate<String> allowedResourceAttributesFilter) {
-    this.converter = new Otel2PrometheusConverter(allowedResourceAttributesFilter);
+    this(
+        allowedResourceAttributesFilter,
+        /* otelScopeLabelsEnabled= */ true,
+        /* otelTargetInfoMetricEnabled= */ true);
+  }
+
+  // Package-private constructor used by builder
+  @SuppressWarnings("InconsistentOverloads")
+  PrometheusMetricReader(
+      @Nullable Predicate<String> allowedResourceAttributesFilter,
+      boolean otelScopeLabelsEnabled,
+      boolean otelTargetInfoMetricEnabled) {
+    this.converter =
+        new Otel2PrometheusConverter(
+            otelScopeLabelsEnabled, otelTargetInfoMetricEnabled, allowedResourceAttributesFilter);
   }
 
   @Override

exporters/prometheus/src/main/java/io/opentelemetry/exporter/prometheus/PrometheusMetricReaderBuilder.java

@@ -0,0 +1,63 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.exporter.prometheus;
+
+import java.util.function.Predicate;
+import javax.annotation.Nullable;
+
+/** Builder for {@link PrometheusMetricReader}. */
+public final class PrometheusMetricReaderBuilder {
+
+  private boolean otelScopeLabelsEnabled = true;
+  private boolean otelTargetInfoMetricEnabled = true;
+  @Nullable private Predicate<String> allowedResourceAttributesFilter;
+
+  PrometheusMetricReaderBuilder() {}
+
+  /**
+   * Sets whether to add OpenTelemetry scope labels (otel_scope_name, otel_scope_version, etc.) to
+   * exported metrics. Default is {@code true}.
+   *
+   * @param otelScopeLabelsEnabled whether to add scope labels
+   * @return this builder
+   */
+  public PrometheusMetricReaderBuilder setOtelScopeLabelsEnabled(boolean otelScopeLabelsEnabled) {
+    this.otelScopeLabelsEnabled = otelScopeLabelsEnabled;
+    return this;
+  }
+
+  /**
+   * Sets whether to export the target_info metric with resource attributes. Default is {@code
+   * true}.
+   *
+   * @param otelTargetInfoMetricEnabled whether to export target_info metric
+   * @return this builder
+   */
+  public PrometheusMetricReaderBuilder setOtelTargetInfoMetricEnabled(
+      boolean otelTargetInfoMetricEnabled) {
+    this.otelTargetInfoMetricEnabled = otelTargetInfoMetricEnabled;
+    return this;
+  }
+
+  /**
+   * Sets a filter to control which resource attributes are added as labels on each exported metric.
+   * If {@code null}, no resource attributes will be added as labels. Default is {@code null}.
+   *
+   * @param allowedResourceAttributesFilter predicate to filter resource attributes, or {@code null}
+   * @return this builder
+   */
+  public PrometheusMetricReaderBuilder setAllowedResourceAttributesFilter(
+      @Nullable Predicate<String> allowedResourceAttributesFilter) {
+    this.allowedResourceAttributesFilter = allowedResourceAttributesFilter;
+    return this;
+  }
+
+  /** Builds a new {@link PrometheusMetricReader}. */
+  public PrometheusMetricReader build() {
+    return new PrometheusMetricReader(
+        allowedResourceAttributesFilter, otelScopeLabelsEnabled, otelTargetInfoMetricEnabled);
+  }
+}

exporters/prometheus/src/main/java/io/opentelemetry/exporter/prometheus/internal/PrometheusComponentProvider.java

@@ -45,6 +45,15 @@ public MetricReader create(DeclarativeConfigProperties config) {
       prometheusBuilder.setHost(host);
     }
 
+    Boolean withoutTargetInfo = config.getBoolean("without_target_info");
+    if (withoutTargetInfo != null) {
+      prometheusBuilder.setOtelTargetInfoMetricEnabled(!withoutTargetInfo);
+    }
+    Boolean withoutScopeInfo = config.getBoolean("without_scope_info");
+    if (withoutScopeInfo != null) {
+      prometheusBuilder.setOtelScopeLabelsEnabled(!withoutScopeInfo);
+    }
+
     DeclarativeConfigProperties withResourceConstantLabels =
         config.getStructured("with_resource_constant_labels");
     if (withResourceConstantLabels != null) {

exporters/prometheus/src/test/java/io/opentelemetry/exporter/prometheus/Otel2PrometheusConverterTest.java

@@ -71,7 +71,10 @@ class Otel2PrometheusConverterTest {
   private static final ObjectMapper OBJECT_MAPPER = new ObjectMapper();
 
   private final Otel2PrometheusConverter converter =
-      new Otel2PrometheusConverter(/* allowedResourceAttributesFilter= */ null);
+      new Otel2PrometheusConverter(
+          /* otelScopeLabelsEnabled= */ true,
+          /* otelTargetInfoMetricEnabled= */ true,
+          /* allowedResourceAttributesFilter= */ null);
 
   @ParameterizedTest
   @MethodSource("metricMetadataArgs")
@@ -201,7 +204,10 @@ void resourceAttributesAddition(
       throws IOException {
 
     Otel2PrometheusConverter converter =
-        new Otel2PrometheusConverter(allowedResourceAttributesFilter);
+        new Otel2PrometheusConverter(
+            /* otelScopeLabelsEnabled= */ true,
+            /* otelTargetInfoMetricEnabled= */ true,
+            allowedResourceAttributesFilter);
 
     ByteArrayOutputStream out = new ByteArrayOutputStream();
     MetricSnapshots snapshots = converter.convert(Collections.singletonList(metricData));
@@ -501,7 +507,10 @@ void validateCacheIsBounded() {
         };
 
     Otel2PrometheusConverter otel2PrometheusConverter =
-        new Otel2PrometheusConverter(/* allowedResourceAttributesFilter= */ countPredicate);
+        new Otel2PrometheusConverter(
+            /* otelScopeLabelsEnabled= */ true,
+            /* otelTargetInfoMetricEnabled= */ true,
+            /* allowedResourceAttributesFilter= */ countPredicate);
 
     // Create 20 different metric data objects with 2 different resource attributes;
     Resource resource1 = Resource.builder().put("cluster", "cluster1").build();

exporters/prometheus/src/test/java/io/opentelemetry/exporter/prometheus/PrometheusHttpServerTest.java

@@ -432,6 +432,8 @@ void stringRepresentation() {
             "PrometheusHttpServer{"
                 + "host=localhost,"
                 + "port=0,"
+                + "otelScopeLabelsEnabled=true,"
+                + "otelTargetInfoMetricEnabled=true,"
                 + "allowedResourceAttributesFilter=null,"
                 + "memoryMode=REUSABLE_DATA,"
                 + "defaultAggregationSelector=DefaultAggregationSelector{COUNTER=default, UP_DOWN_COUNTER=default, HISTOGRAM=default, OBSERVABLE_COUNTER=default, OBSERVABLE_UP_DOWN_COUNTER=default, OBSERVABLE_GAUGE=default, GAUGE=default}"