Create gcp-csm-observability

Author: ejona86

gcp-csm-observability/build.gradle

@@ -0,0 +1,31 @@
+plugins {
+    id "java-library"
+
+    id "ru.vyarus.animalsniffer"
+}
+
+description = "gRPC: GCP CSM Observability"
+
+tasks.named("jar").configure {
+    manifest {
+        attributes('Automatic-Module-Name': 'io.grpc.gcp.csm.observability')
+    }
+}
+
+dependencies {
+    implementation project(':grpc-api'),
+            project(':grpc-core'),
+            project(':grpc-opentelemetry'),
+            project(':grpc-protobuf'),
+            project(':grpc-xds'),
+            libraries.guava.jre, // jre version pulled in via xds
+            libraries.protobuf.java,
+            libraries.opentelemetry.gcp.resources,
+            libraries.opentelemetry.sdk.extension.autoconfigure // opentelemetry.gcp.resources uses compileOnly for this dep
+    testImplementation project(":grpc-testing"),
+            project(":grpc-inprocess"),
+            libraries.opentelemetry.sdk.testing,
+            libraries.assertj.core // opentelemetry.sdk.testing uses compileOnly for this dep
+
+    signature libraries.signature.java
+}

gcp-csm-observability/src/main/java/io/grpc/gcp/csm/observability/CsmObservability.java

@@ -0,0 +1,160 @@
+/*
+ * Copyright 2024 The gRPC Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.grpc.gcp.csm.observability;
+
+import com.google.common.annotations.VisibleForTesting;
+import io.grpc.ExperimentalApi;
+import io.grpc.InternalConfigurator;
+import io.grpc.InternalConfiguratorRegistry;
+import io.grpc.ManagedChannelBuilder;
+import io.grpc.ServerBuilder;
+import io.grpc.opentelemetry.GrpcOpenTelemetry;
+import io.grpc.opentelemetry.InternalGrpcOpenTelemetry;
+import io.opentelemetry.api.OpenTelemetry;
+import java.io.Closeable;
+import java.util.Collection;
+import java.util.Collections;
+
+/**
+ * The entrypoint for GCP's CSM OpenTelemetry metrics functionality in gRPC.
+ *
+ * <p>CsmObservability uses {@link io.opentelemetry.api.OpenTelemetry} APIs for instrumentation.
+ * When no SDK is explicitly added no telemetry data will be collected. See
+ * {@code io.opentelemetry.sdk.OpenTelemetrySdk} for information on how to construct the SDK.
+ */
+@ExperimentalApi("TODO")
+public final class CsmObservability implements Closeable {
+  private final GrpcOpenTelemetry delegate;
+  private final MetadataExchanger exchanger;
+
+  public static Builder newBuilder() {
+    return new Builder();
+  }
+
+  private CsmObservability(Builder builder) {
+    this.delegate = builder.delegate.build();
+    this.exchanger = builder.exchanger;
+  }
+
+  /**
+   * Registers CsmObservability globally, applying its configuration to all subsequently created
+   * gRPC channels and servers.
+   *
+   * <p>Note: Only one of CsmObservability and GrpcOpenTelemetry instance can be registered
+   * globally. Any subsequent call to {@code registerGlobal()} will throw an {@code
+   * IllegalStateException}.
+   */
+  public void registerGlobal() {
+    InternalConfiguratorRegistry.setConfigurators(Collections.singletonList(
+        new InternalConfigurator() {
+          @Override
+          public void configureChannelBuilder(ManagedChannelBuilder<?> channelBuilder) {
+            CsmObservability.this.configureChannelBuilder(channelBuilder);
+          }
+
+          @Override
+          public void configureServerBuilder(ServerBuilder<?> serverBuilder) {
+            CsmObservability.this.configureServerBuilder(serverBuilder);
+          }
+        }));
+  }
+
+  @VisibleForTesting
+  void configureChannelBuilder(ManagedChannelBuilder<?> builder) {
+    delegate.configureChannelBuilder(builder);
+  }
+
+  @VisibleForTesting
+  void configureServerBuilder(ServerBuilder<?> serverBuilder) {
+    delegate.configureServerBuilder(serverBuilder);
+    exchanger.configureServerBuilder(serverBuilder);
+  }
+
+  @Override
+  public void close() {}
+
+  /**
+   * Builder for configuring {@link CsmObservability}.
+   */
+  @ExperimentalApi("TODO")
+  public static final class Builder {
+    private final GrpcOpenTelemetry.Builder delegate = GrpcOpenTelemetry.newBuilder();
+    private final MetadataExchanger exchanger;
+
+    private Builder() {
+      this(new MetadataExchanger());
+    }
+
+    @VisibleForTesting
+    Builder(MetadataExchanger exchanger) {
+      this.exchanger = exchanger;
+      InternalGrpcOpenTelemetry.builderPlugin(delegate, exchanger);
+    }
+
+    /**
+     * Sets the {@link io.opentelemetry.api.OpenTelemetry} entrypoint to use. This can be used to
+     * configure OpenTelemetry by returning the instance created by a
+     * {@code io.opentelemetry.sdk.OpenTelemetrySdkBuilder}.
+     */
+    public Builder sdk(OpenTelemetry sdk) {
+      delegate.sdk(sdk);
+      return this;
+    }
+
+    /**
+     * Adds optionalLabelKey to all the metrics that can provide value for the
+     * optionalLabelKey.
+     */
+    public Builder addOptionalLabel(String optionalLabelKey) {
+      delegate.addOptionalLabel(optionalLabelKey);
+      return this;
+    }
+
+    /**
+     * Enables the specified metrics for collection and export. By default, only a subset of
+     * metrics are enabled.
+     */
+    public Builder enableMetrics(Collection<String> enableMetrics) {
+      delegate.enableMetrics(enableMetrics);
+      return this;
+    }
+
+    /**
+     * Disables the specified metrics from being collected and exported.
+     */
+    public Builder disableMetrics(Collection<String> disableMetrics) {
+      delegate.disableMetrics(disableMetrics);
+      return this;
+    }
+
+    /**
+     * Disable all metrics. If set to true all metrics must be explicitly enabled.
+     */
+    public Builder disableAllMetrics() {
+      delegate.disableAllMetrics();
+      return this;
+    }
+
+    /**
+     * Returns a new {@link CsmObservability} built with the configuration of this {@link
+     * Builder}.
+     */
+    public CsmObservability build() {
+      return new CsmObservability(this);
+    }
+  }
+}