feat: add an enhanced layer for BigQuery Storage v1beta2 client (#48)

* Create a shim layer for the BigQuery Storage API v1beta2.

This change adds a simple shim layer to the BigQuery Read API client.

It is modeled after the shim layer in the BigQuery Storage API v1beta1, where the parameters are simple pass-throughs to the underlying gRPC client stub.

The shim currently does nothing but read default values from the base
client layer and pass them back through.

* Add a resumption strategy for v1beta2 ReadRows.

This change modifies the configuration for the v1beta2 ReadRows API to add a resumption strategy. The resumption strategy will allow the connection to be resumed transparently in the case of transient errors.

* Address feedback about "pass-through" comments.

* Formatting files with mvn com.coveo:fmt-maven-plugin:format

google-cloud-bigquerystorage/src/main/java/com/google/cloud/bigquery/storage/v1beta2/BigQueryReadSettings.java

@@ -0,0 +1,202 @@
+/*
+ * Copyright 2020 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.bigquery.storage.v1beta2;
+
+import com.google.api.core.ApiFunction;
+import com.google.api.core.BetaApi;
+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.rpc.ApiClientHeaderProvider;
+import com.google.api.gax.rpc.ClientContext;
+import com.google.api.gax.rpc.ClientSettings;
+import com.google.api.gax.rpc.ServerStreamingCallSettings;
+import com.google.api.gax.rpc.TransportChannelProvider;
+import com.google.api.gax.rpc.UnaryCallSettings;
+import com.google.cloud.bigquery.storage.v1beta2.stub.EnhancedBigQueryReadStubSettings;
+import java.io.IOException;
+import java.util.List;
+
+/**
+ * Settings class to configure an instance of {@link BigQueryReadClient}.
+ *
+ * <p>The default instance has everything set to sensible defaults:
+ *
+ * <ul>
+ *   <li>The default service address (bigquerystorage.googleapis.com) and default port (443) are
+ *       used.
+ *   <li>Credentials are acquired automatically through Application Default Credentials.
+ *   <li>Retries are configured for idempotent methods but not for non-idempotent methods.
+ * </ul>
+ *
+ * <p>The builder of this class is recursive, so contained classes are themselves builders. When
+ * build() is called, the tree of builders is called to create the complete settings object.
+ *
+ * <p>For example, to set the total timeout of createReadSession to 30 seconds:
+ *
+ * <pre>
+ * <code>
+ * BigQueryReadSettings.Builder BigQueryReadSettingsBuilder =
+ *     BigQueryReadSettings.newBuilder();
+ * BigQueryReadSettingsBuilder.createReadSessionSettings().getRetrySettings().toBuilder()
+ *     .setTotalTimeout(Duration.ofSeconds(30));
+ * BigQueryReadSettings BigQueryReadSettings = BigQueryReadSettingsBuilder.build();
+ * </code>
+ * </pre>
+ */
+@BetaApi
+public class BigQueryReadSettings extends ClientSettings<BigQueryReadSettings> {
+  /** Returns the object with the settings used for calls to createReadSession. */
+  public UnaryCallSettings<CreateReadSessionRequest, ReadSession> createReadSessionSettings() {
+    return getTypedStubSettings().createReadSessionSettings();
+  }
+
+  /** Returns the object with the settings used for calls to readRows. */
+  public ServerStreamingCallSettings<ReadRowsRequest, ReadRowsResponse> readRowsSettings() {
+    return getTypedStubSettings().readRowsSettings();
+  }
+
+  /** Returns the object with the settings used for calls to splitReadStream. */
+  public UnaryCallSettings<SplitReadStreamRequest, SplitReadStreamResponse>
+      splitReadStreamSettings() {
+    return getTypedStubSettings().splitReadStreamSettings();
+  }
+
+  EnhancedBigQueryReadStubSettings getTypedStubSettings() {
+    return (EnhancedBigQueryReadStubSettings) getStubSettings();
+  }
+
+  public static final BigQueryReadSettings create(EnhancedBigQueryReadStubSettings stub)
+      throws IOException {
+    return new BigQueryReadSettings.Builder(stub.toBuilder()).build();
+  }
+
+  /** Returns a builder for the default ExecutorProvider for this service. */
+  public static InstantiatingExecutorProvider.Builder defaultExecutorProviderBuilder() {
+    return EnhancedBigQueryReadStubSettings.defaultExecutorProviderBuilder();
+  }
+
+  /** Returns the default service endpoint. */
+  public static String getDefaultEndpoint() {
+    return EnhancedBigQueryReadStubSettings.getDefaultEndpoint();
+  }
+
+  /** Returns the default service scopes. */
+  public static List<String> getDefaultServiceScopes() {
+    return EnhancedBigQueryReadStubSettings.getDefaultServiceScopes();
+  }
+
+  /** Returns a builder for the default credentials for this service. */
+  public static GoogleCredentialsProvider.Builder defaultCredentialsProviderBuilder() {
+    return EnhancedBigQueryReadStubSettings.defaultCredentialsProviderBuilder();
+  }
+
+  /** Returns a builder for the default ChannelProvider for this service. */
+  public static InstantiatingGrpcChannelProvider.Builder defaultGrpcTransportProviderBuilder() {
+    return EnhancedBigQueryReadStubSettings.defaultGrpcTransportProviderBuilder();
+  }
+
+  public static TransportChannelProvider defaultTransportChannelProvider() {
+    return EnhancedBigQueryReadStubSettings.defaultTransportChannelProvider();
+  }
+
+  @BetaApi("The surface for customizing headers is not stable yet and may change in the future.")
+  public static ApiClientHeaderProvider.Builder defaultApiClientHeaderProviderBuilder() {
+    return EnhancedBigQueryReadStubSettings.defaultApiClientHeaderProviderBuilder();
+  }
+
+  /** Returns a new builder for this class. */
+  public static Builder newBuilder() {
+    return Builder.createDefault();
+  }
+
+  /** Returns a new builder for this class. */
+  public static Builder newBuilder(ClientContext clientContext) {
+    return new Builder(clientContext);
+  }
+
+  /** Returns a builder containing all the values of this settings class. */
+  public Builder toBuilder() {
+    return new Builder(this);
+  }
+
+  protected BigQueryReadSettings(Builder settingsBuilder) throws IOException {
+    super(settingsBuilder);
+  }
+
+  /** Builder for BigQueryReadSettings. */
+  public static class Builder extends ClientSettings.Builder<BigQueryReadSettings, Builder> {
+    protected Builder() throws IOException {
+      this((ClientContext) null);
+    }
+
+    protected Builder(ClientContext clientContext) {
+      super(EnhancedBigQueryReadStubSettings.newBuilder(clientContext));
+    }
+
+    private static Builder createDefault() {
+      return new Builder(EnhancedBigQueryReadStubSettings.newBuilder());
+    }
+
+    protected Builder(BigQueryReadSettings settings) {
+      super(settings.getStubSettings().toBuilder());
+    }
+
+    protected Builder(EnhancedBigQueryReadStubSettings.Builder stubSettings) {
+      super(stubSettings);
+    }
+
+    public EnhancedBigQueryReadStubSettings.Builder getStubSettingsBuilder() {
+      return ((EnhancedBigQueryReadStubSettings.Builder) getStubSettings());
+    }
+
+    // NEXT_MAJOR_VER: remove 'throws Exception'
+    /**
+     * Applies the given settings updater function to all of the unary API methods in this service.
+     *
+     * <p>Note: This method does not support applying settings to streaming methods.
+     */
+    public Builder applyToAllUnaryMethods(
+        ApiFunction<UnaryCallSettings.Builder<?, ?>, Void> settingsUpdater) throws Exception {
+      super.applyToAllUnaryMethods(
+          getStubSettingsBuilder().unaryMethodSettingsBuilders(), settingsUpdater);
+      return this;
+    }
+
+    /** Returns the builder for the settings used for calls to createReadSession. */
+    public UnaryCallSettings.Builder<CreateReadSessionRequest, ReadSession>
+        createReadSessionSettings() {
+      return getStubSettingsBuilder().createReadSessionSettings();
+    }
+
+    /** Returns the builder for the settings used for calls to readRows. */
+    public ServerStreamingCallSettings.Builder<ReadRowsRequest, ReadRowsResponse>
+        readRowsSettings() {
+      return getStubSettingsBuilder().readRowsSettings();
+    }
+
+    /** Returns the builder for the settings used for calls to splitReadStream. */
+    public UnaryCallSettings.Builder<SplitReadStreamRequest, SplitReadStreamResponse>
+        splitReadStreamSettings() {
+      return getStubSettingsBuilder().splitReadStreamSettings();
+    }
+
+    @Override
+    public BigQueryReadSettings build() throws IOException {
+      return new BigQueryReadSettings(this);
+    }
+  }
+}

google-cloud-bigquerystorage/src/main/java/com/google/cloud/bigquery/storage/v1beta2/stub/EnhancedBigQueryReadStub.java

@@ -0,0 +1,121 @@
+/*
+ * Copyright 2020 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.bigquery.storage.v1beta2.stub;
+
+import com.google.api.core.InternalApi;
+import com.google.api.gax.core.BackgroundResource;
+import com.google.api.gax.rpc.ClientContext;
+import com.google.api.gax.rpc.ServerStreamingCallable;
+import com.google.api.gax.rpc.UnaryCallable;
+import com.google.cloud.bigquery.storage.v1beta2.CreateReadSessionRequest;
+import com.google.cloud.bigquery.storage.v1beta2.ReadRowsRequest;
+import com.google.cloud.bigquery.storage.v1beta2.ReadRowsResponse;
+import com.google.cloud.bigquery.storage.v1beta2.ReadSession;
+import com.google.cloud.bigquery.storage.v1beta2.SplitReadStreamRequest;
+import com.google.cloud.bigquery.storage.v1beta2.SplitReadStreamResponse;
+import java.io.IOException;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * Enhanced stub class for BigQuery Storage API.
+ *
+ * <p>This class is for advanced usage and reflects the underlying API directly.
+ */
+public class EnhancedBigQueryReadStub implements BackgroundResource {
+  private final GrpcBigQueryReadStub stub;
+
+  public static EnhancedBigQueryReadStub create(EnhancedBigQueryReadStubSettings settings)
+      throws IOException {
+    // Configure the base settings.
+    BigQueryReadStubSettings.Builder baseSettingsBuilder =
+        BigQueryReadStubSettings.newBuilder()
+            .setTransportChannelProvider(settings.getTransportChannelProvider())
+            .setEndpoint(settings.getEndpoint())
+            .setHeaderProvider(settings.getHeaderProvider())
+            .setCredentialsProvider(settings.getCredentialsProvider())
+            .setStreamWatchdogCheckInterval(settings.getStreamWatchdogCheckInterval())
+            .setStreamWatchdogProvider(settings.getStreamWatchdogProvider());
+
+    baseSettingsBuilder
+        .createReadSessionSettings()
+        .setRetryableCodes(settings.createReadSessionSettings().getRetryableCodes())
+        .setRetrySettings(settings.createReadSessionSettings().getRetrySettings());
+
+    baseSettingsBuilder
+        .readRowsSettings()
+        .setRetryableCodes(settings.readRowsSettings().getRetryableCodes())
+        .setRetrySettings(settings.readRowsSettings().getRetrySettings())
+        .setResumptionStrategy(settings.readRowsSettings().getResumptionStrategy())
+        .setIdleTimeout(settings.readRowsSettings().getIdleTimeout());
+
+    baseSettingsBuilder
+        .splitReadStreamSettings()
+        .setRetryableCodes(settings.splitReadStreamSettings().getRetryableCodes())
+        .setRetrySettings(settings.splitReadStreamSettings().getRetrySettings());
+
+    BigQueryReadStubSettings baseSettings = baseSettingsBuilder.build();
+    ClientContext clientContext = ClientContext.create(baseSettings);
+    GrpcBigQueryReadStub stub = new GrpcBigQueryReadStub(baseSettings, clientContext);
+    return new EnhancedBigQueryReadStub(stub);
+  }
+
+  @InternalApi("Visible for testing")
+  EnhancedBigQueryReadStub(GrpcBigQueryReadStub stub) {
+    this.stub = stub;
+  }
+
+  public UnaryCallable<CreateReadSessionRequest, ReadSession> createReadSessionCallable() {
+    return stub.createReadSessionCallable();
+  }
+
+  public ServerStreamingCallable<ReadRowsRequest, ReadRowsResponse> readRowsCallable() {
+    return stub.readRowsCallable();
+  }
+
+  public UnaryCallable<SplitReadStreamRequest, SplitReadStreamResponse> splitReadStreamCallable() {
+    return stub.splitReadStreamCallable();
+  }
+
+  @Override
+  public void close() {
+    stub.close();
+  }
+
+  @Override
+  public void shutdown() {
+    stub.shutdown();
+  }
+
+  @Override
+  public boolean isShutdown() {
+    return stub.isShutdown();
+  }
+
+  @Override
+  public boolean isTerminated() {
+    return stub.isTerminated();
+  }
+
+  @Override
+  public void shutdownNow() {
+    stub.shutdownNow();
+  }
+
+  @Override
+  public boolean awaitTermination(long duration, TimeUnit unit) throws InterruptedException {
+    return stub.awaitTermination(duration, unit);
+  }
+}