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

README.md

@@ -27,13 +27,13 @@ If you are using Maven, add this to your pom.xml file:
 If you are using Gradle without BOM, add this to your dependencies
 
 ```Groovy
-implementation 'com.google.cloud:google-cloud-domains:0.6.0'
+implementation 'com.google.cloud:google-cloud-domains:0.6.1'
 ```
 
 If you are using SBT, add this to your dependencies
 
 ```Scala
-libraryDependencies += "com.google.cloud" % "google-cloud-domains" % "0.6.0"
+libraryDependencies += "com.google.cloud" % "google-cloud-domains" % "0.6.1"
 ```
 
 ## Authentication

google-cloud-domains/pom.xml

@@ -66,6 +66,10 @@
       <groupId>com.google.api</groupId>
       <artifactId>gax-grpc</artifactId>
     </dependency>
+    <dependency>
+      <groupId>com.google.api</groupId>
+      <artifactId>gax-httpjson</artifactId>
+    </dependency>
     <dependency>
       <groupId>org.threeten</groupId>
       <artifactId>threetenbp</artifactId>
@@ -95,12 +99,24 @@
       <scope>test</scope>
     </dependency>
     <!-- Need testing utility classes for generated gRPC clients tests -->
+    <dependency>
+      <groupId>com.google.api</groupId>
+      <artifactId>gax</artifactId>
+      <classifier>testlib</classifier>
+      <scope>test</scope>
+    </dependency>
     <dependency>
       <groupId>com.google.api</groupId>
       <artifactId>gax-grpc</artifactId>
       <classifier>testlib</classifier>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>com.google.api</groupId>
+      <artifactId>gax-httpjson</artifactId>
+      <classifier>testlib</classifier>
+      <scope>test</scope>
+    </dependency>
   </dependencies>
 
   <profiles>

google-cloud-domains/src/main/java/com/google/cloud/domains/v1/DomainsClient.java

@@ -19,6 +19,7 @@
 import com.google.api.core.ApiFuture;
 import com.google.api.core.ApiFutures;
 import com.google.api.gax.core.BackgroundResource;
+import com.google.api.gax.httpjson.longrunning.OperationsClient;
 import com.google.api.gax.longrunning.OperationFuture;
 import com.google.api.gax.paging.AbstractFixedSizeCollection;
 import com.google.api.gax.paging.AbstractPage;
@@ -30,7 +31,6 @@
 import com.google.cloud.domains.v1.stub.DomainsStubSettings;
 import com.google.common.util.concurrent.MoreExecutors;
 import com.google.longrunning.Operation;
-import com.google.longrunning.OperationsClient;
 import com.google.protobuf.Empty;
 import com.google.protobuf.FieldMask;
 import com.google.type.Money;
@@ -103,13 +103,28 @@
  * DomainsClient domainsClient = DomainsClient.create(domainsSettings);
  * }</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.
+ * DomainsSettings domainsSettings =
+ *     DomainsSettings.newBuilder()
+ *         .setTransportChannelProvider(
+ *             DomainsSettings.defaultHttpJsonTransportProviderBuilder().build())
+ *         .build();
+ * DomainsClient domainsClient = DomainsClient.create(domainsSettings);
+ * }</pre>
+ *
  * <p>Please refer to the GitHub repository's samples for more quickstart code snippets.
  */
 @Generated("by gapic-generator-java")
 public class DomainsClient implements BackgroundResource {
   private final DomainsSettings settings;
   private final DomainsStub stub;
-  private final OperationsClient operationsClient;
+  private final OperationsClient httpJsonOperationsClient;
+  private final com.google.longrunning.OperationsClient operationsClient;
 
   /** Constructs an instance of DomainsClient with default settings. */
   public static final DomainsClient create() throws IOException {
@@ -139,13 +154,17 @@ public static final DomainsClient create(DomainsStub stub) {
   protected DomainsClient(DomainsSettings settings) throws IOException {
     this.settings = settings;
     this.stub = ((DomainsStubSettings) settings.getStubSettings()).createStub();
-    this.operationsClient = OperationsClient.create(this.stub.getOperationsStub());
+    this.operationsClient =
+        com.google.longrunning.OperationsClient.create(this.stub.getOperationsStub());
+    this.httpJsonOperationsClient = OperationsClient.create(this.stub.getHttpJsonOperationsStub());
   }
 
   protected DomainsClient(DomainsStub stub) {
     this.settings = null;
     this.stub = stub;
-    this.operationsClient = OperationsClient.create(this.stub.getOperationsStub());
+    this.operationsClient =
+        com.google.longrunning.OperationsClient.create(this.stub.getOperationsStub());
+    this.httpJsonOperationsClient = OperationsClient.create(this.stub.getHttpJsonOperationsStub());
   }
 
   public final DomainsSettings getSettings() {
@@ -160,10 +179,18 @@ public DomainsStub getStub() {
    * Returns the OperationsClient that can be used to query the status of a long-running operation
    * returned by another API method call.
    */
-  public final OperationsClient getOperationsClient() {
+  public final com.google.longrunning.OperationsClient getOperationsClient() {
     return operationsClient;
   }
 
+  /**
+   * Returns the OperationsClient that can be used to query the status of a long-running operation
+   * returned by another API method call.
+   */
+  public final OperationsClient getHttpJsonOperationsClient() {
+    return httpJsonOperationsClient;
+  }
+
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
    * Searches for available domain names similar to the provided query.

google-cloud-domains/src/main/java/com/google/cloud/domains/v1/DomainsSettings.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;
@@ -228,11 +229,18 @@ public static GoogleCredentialsProvider.Builder defaultCredentialsProviderBuilde
     return DomainsStubSettings.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 DomainsStubSettings.defaultGrpcTransportProviderBuilder();
   }
 
+  /** Returns a builder for the default REST ChannelProvider for this service. */
+  @BetaApi
+  public static InstantiatingHttpJsonChannelProvider.Builder
+      defaultHttpJsonTransportProviderBuilder() {
+    return DomainsStubSettings.defaultHttpJsonTransportProviderBuilder();
+  }
+
   public static TransportChannelProvider defaultTransportChannelProvider() {
     return DomainsStubSettings.defaultTransportChannelProvider();
   }
@@ -242,11 +250,17 @@ public static ApiClientHeaderProvider.Builder defaultApiClientHeaderProviderBuil
     return DomainsStubSettings.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);
@@ -284,6 +298,11 @@ private static Builder createDefault() {
       return new Builder(DomainsStubSettings.newBuilder());
     }
 
+    @BetaApi
+    private static Builder createHttpJsonDefault() {
+      return new Builder(DomainsStubSettings.newHttpJsonBuilder());
+    }
+
     public DomainsStubSettings.Builder getStubSettingsBuilder() {
       return ((DomainsStubSettings.Builder) getStubSettings());
     }

google-cloud-domains/src/main/java/com/google/cloud/domains/v1/stub/DomainsStub.java

@@ -58,7 +58,11 @@
 public abstract class DomainsStub implements BackgroundResource {
 
   public OperationsStub getOperationsStub() {
-    throw new UnsupportedOperationException("Not implemented: getOperationsStub()");
+    return null;
+  }
+
+  public com.google.api.gax.httpjson.longrunning.stub.OperationsStub getHttpJsonOperationsStub() {
+    return null;
   }
 
   public UnaryCallable<SearchDomainsRequest, SearchDomainsResponse> searchDomainsCallable() {

google-cloud-domains/src/main/java/com/google/cloud/domains/v1/stub/DomainsStubSettings.java

@@ -28,6 +28,9 @@
 import com.google.api.gax.grpc.GrpcTransportChannel;
 import com.google.api.gax.grpc.InstantiatingGrpcChannelProvider;
 import com.google.api.gax.grpc.ProtoOperationTransformers;
+import com.google.api.gax.httpjson.GaxHttpJsonProperties;
+import com.google.api.gax.httpjson.HttpJsonTransportChannel;
+import com.google.api.gax.httpjson.InstantiatingHttpJsonChannelProvider;
 import com.google.api.gax.longrunning.OperationSnapshot;
 import com.google.api.gax.longrunning.OperationTimedPollAlgorithm;
 import com.google.api.gax.retrying.RetrySettings;
@@ -360,6 +363,11 @@ public DomainsStub createStub() throws IOException {
         .equals(GrpcTransportChannel.getGrpcTransportName())) {
       return GrpcDomainsStub.create(this);
     }
+    if (getTransportChannelProvider()
+        .getTransportName()
+        .equals(HttpJsonTransportChannel.getHttpJsonTransportName())) {
+      return HttpJsonDomainsStub.create(this);
+    }
     throw new UnsupportedOperationException(
         String.format(
             "Transport not supported: %s", getTransportChannelProvider().getTransportName()));
@@ -392,29 +400,54 @@ public static GoogleCredentialsProvider.Builder defaultCredentialsProviderBuilde
         .setUseJwtAccessWithScope(true);
   }
 
-  /** 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 InstantiatingGrpcChannelProvider.newBuilder()
         .setMaxInboundMessageSize(Integer.MAX_VALUE);
   }
 
+  /** Returns a builder for the default REST ChannelProvider for this service. */
+  @BetaApi
+  public static InstantiatingHttpJsonChannelProvider.Builder
+      defaultHttpJsonTransportProviderBuilder() {
+    return InstantiatingHttpJsonChannelProvider.newBuilder();
+  }
+
   public static TransportChannelProvider defaultTransportChannelProvider() {
     return defaultGrpcTransportProviderBuilder().build();
   }
 
   @BetaApi("The surface for customizing headers is not stable yet and may change in the future.")
-  public static ApiClientHeaderProvider.Builder defaultApiClientHeaderProviderBuilder() {
+  public static ApiClientHeaderProvider.Builder defaultGrpcApiClientHeaderProviderBuilder() {
     return ApiClientHeaderProvider.newBuilder()
         .setGeneratedLibToken("gapic", GaxProperties.getLibraryVersion(DomainsStubSettings.class))
         .setTransportToken(
             GaxGrpcProperties.getGrpcTokenName(), GaxGrpcProperties.getGrpcVersion());
   }
 
-  /** Returns a new builder for this class. */
+  @BetaApi("The surface for customizing headers is not stable yet and may change in the future.")
+  public static ApiClientHeaderProvider.Builder defaultHttpJsonApiClientHeaderProviderBuilder() {
+    return ApiClientHeaderProvider.newBuilder()
+        .setGeneratedLibToken("gapic", GaxProperties.getLibraryVersion(DomainsStubSettings.class))
+        .setTransportToken(
+            GaxHttpJsonProperties.getHttpJsonTokenName(),
+            GaxHttpJsonProperties.getHttpJsonVersion());
+  }
+
+  public static ApiClientHeaderProvider.Builder defaultApiClientHeaderProviderBuilder() {
+    return DomainsStubSettings.defaultGrpcApiClientHeaderProviderBuilder();
+  }
+
+  /** Returns a new gRPC builder for this class. */
   public static Builder newBuilder() {
     return Builder.createDefault();
   }
 
+  /** Returns a new REST builder for this class. */
+  public static Builder newHttpJsonBuilder() {
+    return Builder.createHttpJsonDefault();
+  }
+
   /** Returns a new builder for this class. */
   public static Builder newBuilder(ClientContext clientContext) {
     return new Builder(clientContext);
@@ -658,6 +691,19 @@ private static Builder createDefault() {
       return initDefaults(builder);
     }
 
+    private static Builder createHttpJsonDefault() {
+      Builder builder = new Builder(((ClientContext) null));
+
+      builder.setTransportChannelProvider(defaultHttpJsonTransportProviderBuilder().build());
+      builder.setCredentialsProvider(defaultCredentialsProviderBuilder().build());
+      builder.setInternalHeaderProvider(defaultHttpJsonApiClientHeaderProviderBuilder().build());
+      builder.setEndpoint(getDefaultEndpoint());
+      builder.setMtlsEndpoint(getDefaultMtlsEndpoint());
+      builder.setSwitchToMtlsEndpointAllowed(true);
+
+      return initDefaults(builder);
+    }
+
     private static Builder initDefaults(Builder builder) {
       builder
           .searchDomainsSettings()