feat: Enable REST transport for most of Java and Go clients

google-cloud-trace/src/main/java/com/google/cloud/trace/v1/TraceServiceClient.java

@@ -107,6 +107,20 @@
  * TraceServiceClient traceServiceClient = TraceServiceClient.create(traceServiceSettings);
  * }</pre>
  *
+ * <p>To use REST (HTTP1.1/JSON) transport (instead of gRPC) for sending and receiving requests over
+ * the wire:
+ *
+ * <pre>{@code
+ * // This snippet has been automatically generated for illustrative purposes only.
+ * // It may require modifications to work in your environment.
+ * TraceServiceSettings traceServiceSettings =
+ *     TraceServiceSettings.newBuilder()
+ *         .setTransportChannelProvider(
+ *             TraceServiceSettings.defaultHttpJsonTransportProviderBuilder().build())
+ *         .build();
+ * TraceServiceClient traceServiceClient = TraceServiceClient.create(traceServiceSettings);
+ * }</pre>
+ *
  * <p>Please refer to the GitHub repository's samples for more quickstart code snippets.
  */
 @Generated("by gapic-generator-java")

google-cloud-trace/src/main/java/com/google/cloud/trace/v1/TraceServiceSettings.java

@@ -23,6 +23,7 @@
 import com.google.api.gax.core.GoogleCredentialsProvider;
 import com.google.api.gax.core.InstantiatingExecutorProvider;
 import com.google.api.gax.grpc.InstantiatingGrpcChannelProvider;
+import com.google.api.gax.httpjson.InstantiatingHttpJsonChannelProvider;
 import com.google.api.gax.rpc.ApiClientHeaderProvider;
 import com.google.api.gax.rpc.ClientContext;
 import com.google.api.gax.rpc.ClientSettings;
@@ -117,11 +118,18 @@ public static GoogleCredentialsProvider.Builder defaultCredentialsProviderBuilde
     return TraceServiceStubSettings.defaultCredentialsProviderBuilder();
   }
 
-  /** Returns a builder for the default ChannelProvider for this service. */
+  /** Returns a builder for the default gRPC ChannelProvider for this service. */
   public static InstantiatingGrpcChannelProvider.Builder defaultGrpcTransportProviderBuilder() {
     return TraceServiceStubSettings.defaultGrpcTransportProviderBuilder();
   }
 
+  /** Returns a builder for the default REST ChannelProvider for this service. */
+  @BetaApi
+  public static InstantiatingHttpJsonChannelProvider.Builder
+      defaultHttpJsonTransportProviderBuilder() {
+    return TraceServiceStubSettings.defaultHttpJsonTransportProviderBuilder();
+  }
+
   public static TransportChannelProvider defaultTransportChannelProvider() {
     return TraceServiceStubSettings.defaultTransportChannelProvider();
   }
@@ -131,11 +139,17 @@ public static ApiClientHeaderProvider.Builder defaultApiClientHeaderProviderBuil
     return TraceServiceStubSettings.defaultApiClientHeaderProviderBuilder();
   }
 
-  /** Returns a new builder for this class. */
+  /** Returns a new gRPC builder for this class. */
   public static Builder newBuilder() {
     return Builder.createDefault();
   }
 
+  /** Returns a new REST builder for this class. */
+  @BetaApi
+  public static Builder newHttpJsonBuilder() {
+    return Builder.createHttpJsonDefault();
+  }
+
   /** Returns a new builder for this class. */
   public static Builder newBuilder(ClientContext clientContext) {
     return new Builder(clientContext);
@@ -173,6 +187,11 @@ private static Builder createDefault() {
       return new Builder(TraceServiceStubSettings.newBuilder());
     }
 
+    @BetaApi
+    private static Builder createHttpJsonDefault() {
+      return new Builder(TraceServiceStubSettings.newHttpJsonBuilder());
+    }
+
     public TraceServiceStubSettings.Builder getStubSettingsBuilder() {
       return ((TraceServiceStubSettings.Builder) getStubSettings());
     }

google-cloud-trace/src/main/java/com/google/cloud/trace/v1/stub/HttpJsonTraceServiceCallableFactory.java

@@ -0,0 +1,105 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * 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
+ *
+ *      https://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 com.google.cloud.trace.v1.stub;
+
+import com.google.api.core.BetaApi;
+import com.google.api.gax.httpjson.HttpJsonCallSettings;
+import com.google.api.gax.httpjson.HttpJsonCallableFactory;
+import com.google.api.gax.httpjson.HttpJsonOperationSnapshotCallable;
+import com.google.api.gax.httpjson.HttpJsonStubCallableFactory;
+import com.google.api.gax.httpjson.longrunning.stub.OperationsStub;
+import com.google.api.gax.rpc.BatchingCallSettings;
+import com.google.api.gax.rpc.ClientContext;
+import com.google.api.gax.rpc.OperationCallSettings;
+import com.google.api.gax.rpc.OperationCallable;
+import com.google.api.gax.rpc.PagedCallSettings;
+import com.google.api.gax.rpc.ServerStreamingCallSettings;
+import com.google.api.gax.rpc.ServerStreamingCallable;
+import com.google.api.gax.rpc.UnaryCallSettings;
+import com.google.api.gax.rpc.UnaryCallable;
+import com.google.longrunning.Operation;
+import javax.annotation.Generated;
+
+// AUTO-GENERATED DOCUMENTATION AND CLASS.
+/**
+ * REST callable factory implementation for the TraceService service API.
+ *
+ * <p>This class is for advanced usage.
+ */
+@Generated("by gapic-generator-java")
+@BetaApi
+public class HttpJsonTraceServiceCallableFactory
+    implements HttpJsonStubCallableFactory<Operation, OperationsStub> {
+
+  @Override
+  public <RequestT, ResponseT> UnaryCallable<RequestT, ResponseT> createUnaryCallable(
+      HttpJsonCallSettings<RequestT, ResponseT> httpJsonCallSettings,
+      UnaryCallSettings<RequestT, ResponseT> callSettings,
+      ClientContext clientContext) {
+    return HttpJsonCallableFactory.createUnaryCallable(
+        httpJsonCallSettings, callSettings, clientContext);
+  }
+
+  @Override
+  public <RequestT, ResponseT, PagedListResponseT>
+      UnaryCallable<RequestT, PagedListResponseT> createPagedCallable(
+          HttpJsonCallSettings<RequestT, ResponseT> httpJsonCallSettings,
+          PagedCallSettings<RequestT, ResponseT, PagedListResponseT> callSettings,
+          ClientContext clientContext) {
+    return HttpJsonCallableFactory.createPagedCallable(
+        httpJsonCallSettings, callSettings, clientContext);
+  }
+
+  @Override
+  public <RequestT, ResponseT> UnaryCallable<RequestT, ResponseT> createBatchingCallable(
+      HttpJsonCallSettings<RequestT, ResponseT> httpJsonCallSettings,
+      BatchingCallSettings<RequestT, ResponseT> callSettings,
+      ClientContext clientContext) {
+    return HttpJsonCallableFactory.createBatchingCallable(
+        httpJsonCallSettings, callSettings, clientContext);
+  }
+
+  @BetaApi(
+      "The surface for long-running operations is not stable yet and may change in the future.")
+  @Override
+  public <RequestT, ResponseT, MetadataT>
+      OperationCallable<RequestT, ResponseT, MetadataT> createOperationCallable(
+          HttpJsonCallSettings<RequestT, Operation> httpJsonCallSettings,
+          OperationCallSettings<RequestT, ResponseT, MetadataT> callSettings,
+          ClientContext clientContext,
+          OperationsStub operationsStub) {
+    UnaryCallable<RequestT, Operation> innerCallable =
+        HttpJsonCallableFactory.createBaseUnaryCallable(
+            httpJsonCallSettings, callSettings.getInitialCallSettings(), clientContext);
+    HttpJsonOperationSnapshotCallable<RequestT, Operation> initialCallable =
+        new HttpJsonOperationSnapshotCallable<RequestT, Operation>(
+            innerCallable,
+            httpJsonCallSettings.getMethodDescriptor().getOperationSnapshotFactory());
+    return HttpJsonCallableFactory.createOperationCallable(
+        callSettings, clientContext, operationsStub.longRunningClient(), initialCallable);
+  }
+
+  @Override
+  public <RequestT, ResponseT>
+      ServerStreamingCallable<RequestT, ResponseT> createServerStreamingCallable(
+          HttpJsonCallSettings<RequestT, ResponseT> httpJsonCallSettings,
+          ServerStreamingCallSettings<RequestT, ResponseT> callSettings,
+          ClientContext clientContext) {
+    return HttpJsonCallableFactory.createServerStreamingCallable(
+        httpJsonCallSettings, callSettings, clientContext);
+  }
+}