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

google-cloud-billing/src/main/java/com/google/cloud/billing/v1/CloudBillingClient.java

@@ -102,6 +102,20 @@
  * CloudBillingClient cloudBillingClient = CloudBillingClient.create(cloudBillingSettings);
  * }</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.
+ * CloudBillingSettings cloudBillingSettings =
+ *     CloudBillingSettings.newBuilder()
+ *         .setTransportChannelProvider(
+ *             CloudBillingSettings.defaultHttpJsonTransportProviderBuilder().build())
+ *         .build();
+ * CloudBillingClient cloudBillingClient = CloudBillingClient.create(cloudBillingSettings);
+ * }</pre>
+ *
  * <p>Please refer to the GitHub repository's samples for more quickstart code snippets.
  */
 @Generated("by gapic-generator-java")

google-cloud-billing/src/main/java/com/google/cloud/billing/v1/CloudBillingSettings.java

@@ -24,6 +24,7 @@
 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;
@@ -162,11 +163,18 @@ public static GoogleCredentialsProvider.Builder defaultCredentialsProviderBuilde
     return CloudBillingStubSettings.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 CloudBillingStubSettings.defaultGrpcTransportProviderBuilder();
   }
 
+  /** Returns a builder for the default REST ChannelProvider for this service. */
+  @BetaApi
+  public static InstantiatingHttpJsonChannelProvider.Builder
+      defaultHttpJsonTransportProviderBuilder() {
+    return CloudBillingStubSettings.defaultHttpJsonTransportProviderBuilder();
+  }
+
   public static TransportChannelProvider defaultTransportChannelProvider() {
     return CloudBillingStubSettings.defaultTransportChannelProvider();
   }
@@ -176,11 +184,17 @@ public static ApiClientHeaderProvider.Builder defaultApiClientHeaderProviderBuil
     return CloudBillingStubSettings.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);
@@ -218,6 +232,11 @@ private static Builder createDefault() {
       return new Builder(CloudBillingStubSettings.newBuilder());
     }
 
+    @BetaApi
+    private static Builder createHttpJsonDefault() {
+      return new Builder(CloudBillingStubSettings.newHttpJsonBuilder());
+    }
+
     public CloudBillingStubSettings.Builder getStubSettingsBuilder() {
       return ((CloudBillingStubSettings.Builder) getStubSettings());
     }

google-cloud-billing/src/main/java/com/google/cloud/billing/v1/CloudCatalogClient.java

@@ -98,6 +98,20 @@
  * CloudCatalogClient cloudCatalogClient = CloudCatalogClient.create(cloudCatalogSettings);
  * }</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.
+ * CloudCatalogSettings cloudCatalogSettings =
+ *     CloudCatalogSettings.newBuilder()
+ *         .setTransportChannelProvider(
+ *             CloudCatalogSettings.defaultHttpJsonTransportProviderBuilder().build())
+ *         .build();
+ * CloudCatalogClient cloudCatalogClient = CloudCatalogClient.create(cloudCatalogSettings);
+ * }</pre>
+ *
  * <p>Please refer to the GitHub repository's samples for more quickstart code snippets.
  */
 @Generated("by gapic-generator-java")

google-cloud-billing/src/main/java/com/google/cloud/billing/v1/CloudCatalogSettings.java

@@ -24,6 +24,7 @@
 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;
@@ -108,11 +109,18 @@ public static GoogleCredentialsProvider.Builder defaultCredentialsProviderBuilde
     return CloudCatalogStubSettings.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 CloudCatalogStubSettings.defaultGrpcTransportProviderBuilder();
   }
 
+  /** Returns a builder for the default REST ChannelProvider for this service. */
+  @BetaApi
+  public static InstantiatingHttpJsonChannelProvider.Builder
+      defaultHttpJsonTransportProviderBuilder() {
+    return CloudCatalogStubSettings.defaultHttpJsonTransportProviderBuilder();
+  }
+
   public static TransportChannelProvider defaultTransportChannelProvider() {
     return CloudCatalogStubSettings.defaultTransportChannelProvider();
   }
@@ -122,11 +130,17 @@ public static ApiClientHeaderProvider.Builder defaultApiClientHeaderProviderBuil
     return CloudCatalogStubSettings.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);
@@ -164,6 +178,11 @@ private static Builder createDefault() {
       return new Builder(CloudCatalogStubSettings.newBuilder());
     }
 
+    @BetaApi
+    private static Builder createHttpJsonDefault() {
+      return new Builder(CloudCatalogStubSettings.newHttpJsonBuilder());
+    }
+
     public CloudCatalogStubSettings.Builder getStubSettingsBuilder() {
       return ((CloudCatalogStubSettings.Builder) getStubSettings());
     }

google-cloud-billing/src/main/java/com/google/cloud/billing/v1/stub/CloudBillingStubSettings.java

@@ -28,6 +28,9 @@
 import com.google.api.gax.grpc.GaxGrpcProperties;
 import com.google.api.gax.grpc.GrpcTransportChannel;
 import com.google.api.gax.grpc.InstantiatingGrpcChannelProvider;
+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.retrying.RetrySettings;
 import com.google.api.gax.rpc.ApiCallContext;
 import com.google.api.gax.rpc.ApiClientHeaderProvider;
@@ -327,6 +330,11 @@ public CloudBillingStub createStub() throws IOException {
         .equals(GrpcTransportChannel.getGrpcTransportName())) {
       return GrpcCloudBillingStub.create(this);
     }
+    if (getTransportChannelProvider()
+        .getTransportName()
+        .equals(HttpJsonTransportChannel.getHttpJsonTransportName())) {
+      return HttpJsonCloudBillingStub.create(this);
+    }
     throw new UnsupportedOperationException(
         String.format(
             "Transport not supported: %s", getTransportChannelProvider().getTransportName()));
@@ -359,30 +367,56 @@ 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(CloudBillingStubSettings.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(CloudBillingStubSettings.class))
+        .setTransportToken(
+            GaxHttpJsonProperties.getHttpJsonTokenName(),
+            GaxHttpJsonProperties.getHttpJsonVersion());
+  }
+
+  public static ApiClientHeaderProvider.Builder defaultApiClientHeaderProviderBuilder() {
+    return CloudBillingStubSettings.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);
@@ -554,6 +588,19 @@ 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
           .getBillingAccountSettings()

google-cloud-billing/src/main/java/com/google/cloud/billing/v1/stub/CloudCatalogStubSettings.java

@@ -28,6 +28,9 @@
 import com.google.api.gax.grpc.GaxGrpcProperties;
 import com.google.api.gax.grpc.GrpcTransportChannel;
 import com.google.api.gax.grpc.InstantiatingGrpcChannelProvider;
+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.retrying.RetrySettings;
 import com.google.api.gax.rpc.ApiCallContext;
 import com.google.api.gax.rpc.ApiClientHeaderProvider;
@@ -225,6 +228,11 @@ public CloudCatalogStub createStub() throws IOException {
         .equals(GrpcTransportChannel.getGrpcTransportName())) {
       return GrpcCloudCatalogStub.create(this);
     }
+    if (getTransportChannelProvider()
+        .getTransportName()
+        .equals(HttpJsonTransportChannel.getHttpJsonTransportName())) {
+      return HttpJsonCloudCatalogStub.create(this);
+    }
     throw new UnsupportedOperationException(
         String.format(
             "Transport not supported: %s", getTransportChannelProvider().getTransportName()));
@@ -257,30 +265,56 @@ 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(CloudCatalogStubSettings.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(CloudCatalogStubSettings.class))
+        .setTransportToken(
+            GaxHttpJsonProperties.getHttpJsonTokenName(),
+            GaxHttpJsonProperties.getHttpJsonVersion());
+  }
+
+  public static ApiClientHeaderProvider.Builder defaultApiClientHeaderProviderBuilder() {
+    return CloudCatalogStubSettings.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);
@@ -372,6 +406,19 @@ 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
           .listServicesSettings()