Added tests for gRPC retries.

pom.xml

@@ -140,6 +140,12 @@
       <artifactId>grpc-all</artifactId>
       <version>0.9.0</version>
     </dependency>
+    <dependency>
+      <groupId>io.grpc</groupId>
+      <artifactId>grpc-interop-testing</artifactId>
+      <version>0.9.0</version>
+      <scope>test</scope>
+    </dependency>
 
     <!-- Used to test the custom builder logic -->
     <dependency>

src/main/java/com/google/cloud/genomics/utils/grpc/GenomicsChannel.java

@@ -1,13 +1,23 @@
+/*
+ * Copyright (C) 2015 Google Inc.
+ *
+ * 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 com.google.cloud.genomics.utils.grpc;
 
-import com.google.auth.oauth2.GoogleCredentials;
-import com.google.cloud.genomics.utils.GenomicsFactory;
-
 import io.grpc.CallOptions;
 import io.grpc.Channel;
-import io.grpc.ManagedChannel;
 import io.grpc.ClientCall;
 import io.grpc.ClientInterceptors;
+import io.grpc.ManagedChannel;
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
 import io.grpc.auth.ClientAuthInterceptor;
@@ -26,10 +36,13 @@
 
 import javax.net.ssl.SSLException;
 
+import com.google.auth.oauth2.GoogleCredentials;
+import com.google.cloud.genomics.utils.GenomicsFactory;
+
 /**
  * A convenience class for creating gRPC channels to the Google Genomics API.
  */
-public class GenomicsChannel extends Channel {
+public class GenomicsChannel extends ManagedChannel {
   private static final String GENOMICS_ENDPOINT = "genomics.googleapis.com";
   private static final String GENOMICS_SCOPE = "https://www.googleapis.com/auth/genomics";
   private static final String API_KEY_HEADER = "X-Goog-Api-Key";
@@ -40,12 +53,11 @@ public class GenomicsChannel extends Channel {
   // the shutdown method and the ClientInterceptors do not return the ManagedChannel instance.
   private final ManagedChannel managedChannel;
   private final Channel delegate;
-  
+
   private ManagedChannel getGenomicsManagedChannel() throws SSLException {
     // Java 8's implementation of GCM ciphers is extremely slow. Therefore we disable
     // them here.
-    List<String> defaultCiphers =
-        GrpcSslContexts.forClient().ciphers(null).build().cipherSuites();
+    List<String> defaultCiphers = GrpcSslContexts.forClient().ciphers(null).build().cipherSuites();
     List<String> performantCiphers = new ArrayList<>();
     for (String cipher : defaultCiphers) {
       if (!cipher.contains("GCM")) {
@@ -55,75 +67,96 @@ private ManagedChannel getGenomicsManagedChannel() throws SSLException {
 
     return NettyChannelBuilder.forAddress(GENOMICS_ENDPOINT, 443)
         .negotiationType(NegotiationType.TLS)
-        .sslContext(GrpcSslContexts.forClient().ciphers(performantCiphers).build())
-        .build();
+        .sslContext(GrpcSslContexts.forClient().ciphers(performantCiphers).build()).build();
   }
-  
+
   private GenomicsChannel(String apiKey) throws SSLException {
     managedChannel = getGenomicsManagedChannel();
     Metadata headers = new Metadata();
     Metadata.Key<String> apiKeyHeader =
         Metadata.Key.of(API_KEY_HEADER, Metadata.ASCII_STRING_MARSHALLER);
     headers.put(apiKeyHeader, apiKey);
-    delegate = ClientInterceptors.intercept(managedChannel,
-        MetadataUtils.newAttachHeadersInterceptor(headers)); 
+    delegate =
+        ClientInterceptors.intercept(managedChannel,
+            MetadataUtils.newAttachHeadersInterceptor(headers));
   }
-  
+
   private GenomicsChannel(GoogleCredentials creds) throws SSLException {
     managedChannel = getGenomicsManagedChannel();
-    creds = creds.createScoped(
-        Arrays.asList(GENOMICS_SCOPE));
-    ClientAuthInterceptor interceptor = new ClientAuthInterceptor(creds,
-        Executors.newSingleThreadExecutor());
+    creds = creds.createScoped(Arrays.asList(GENOMICS_SCOPE));
+    ClientAuthInterceptor interceptor =
+        new ClientAuthInterceptor(creds, Executors.newSingleThreadExecutor());
     delegate = ClientInterceptors.intercept(managedChannel, interceptor);
   }
-  
+
   @Override
   public <RequestT, ResponseT> ClientCall<RequestT, ResponseT> newCall(
       MethodDescriptor<RequestT, ResponseT> arg0, CallOptions arg1) {
     return delegate.newCall(arg0, arg1);
   }
 
   /**
-   * @see io.grpc.ManagedChannel#shutdownNow()
-   */
-  public void shutdownNow() {
-    managedChannel.shutdownNow();
-  }
-
-  /**
-   * @throws InterruptedException 
+   * @throws InterruptedException
    * @see io.grpc.ManagedChannel#shutdown()
    * @see io.grpc.ManagedChannel#awaitTermination(long, TimeUnit)
    */
   public void shutdown(long timeout, TimeUnit unit) throws InterruptedException {
     managedChannel.shutdown().awaitTermination(timeout, unit);
   }
 
+
+  @Override
+  public boolean awaitTermination(long time, TimeUnit unit) throws InterruptedException {
+    return managedChannel.awaitTermination(time, unit);
+  }
+
+  @Override
+  public boolean isShutdown() {
+    return managedChannel.isShutdown();
+  }
+
+  @Override
+  public boolean isTerminated() {
+    return managedChannel.isTerminated();
+  }
+
+  @Override
+  public ManagedChannel shutdown() {
+    return managedChannel.shutdown();
+  }
+
+  @Override
+  public ManagedChannel shutdownNow() {
+    return managedChannel.shutdownNow();
+  }
+
+  @Override
+  public String authority() {
+    return managedChannel.authority();
+  }
+
   /**
-   * Creates a new gRPC channel to the Google Genomics API, using the application
-   * default credentials for auth.
+   * Creates a new gRPC channel to the Google Genomics API, using the application default
+   * credentials for auth.
    */
   public static GenomicsChannel fromDefaultCreds() throws IOException {
     return fromCreds(GoogleCredentials.getApplicationDefault());
   }
-  
+
   /**
-   * Creates a new gRPC channel to the Google Genomics API, using the provided
-   * api key for auth.
+   * Creates a new gRPC channel to the Google Genomics API, using the provided api key for auth.
    */
   public static GenomicsChannel fromApiKey(String apiKey) throws SSLException {
     return new GenomicsChannel(apiKey);
   }
-  
+
   /**
-   * Creates a new gRPC channel to the Google Genomics API, using the provided
-   * credentials for auth.
+   * Creates a new gRPC channel to the Google Genomics API, using the provided credentials for auth.
    */
   public static GenomicsChannel fromCreds(GoogleCredentials creds) throws IOException {
     return new GenomicsChannel(creds);
   }
-  
+
   /**
    * Initialize auth for a gRPC channel from OfflineAuth or the application default credentials.
    * 
@@ -132,23 +165,19 @@ public static GenomicsChannel fromCreds(GoogleCredentials creds) throws IOExcept
    * https://developers.google.com/identity/protocols/application-default-credentials
    * 
    * @param auth An OfflineAuth object.
-   * @return The gRPC channel authorized using either the information in the OfflineAuth or application default credentials.
+   * @return The gRPC channel authorized using either the information in the OfflineAuth or
+   *         application default credentials.
    * @throws IOException
    * @throws GeneralSecurityException
    */
-  public static GenomicsChannel fromOfflineAuth(GenomicsFactory.OfflineAuth auth) throws IOException, GeneralSecurityException {
-    if(auth.hasUserCredentials()) {
+  public static GenomicsChannel fromOfflineAuth(GenomicsFactory.OfflineAuth auth)
+      throws IOException, GeneralSecurityException {
+    if (auth.hasUserCredentials()) {
       return fromCreds(auth.getUserCredentials());
-    } else if(auth.hasApiKey()) {
+    } else if (auth.hasApiKey()) {
       return fromApiKey(auth.apiKey);
     }
     // Fall back to Default Credentials if the user did not specify user credentials or an api key.
     return fromDefaultCreds();
   }
-
-  @Override
-  public String authority() {
-    return delegate.authority();
-  }
 }
-

src/main/java/com/google/cloud/genomics/utils/grpc/GenomicsStreamIterator.java

@@ -13,16 +13,16 @@
  */
 package com.google.cloud.genomics.utils.grpc;
 
+import io.grpc.ManagedChannel;
+
 import java.io.IOException;
-import java.security.GeneralSecurityException;
 import java.util.Iterator;
 import java.util.List;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
 import com.google.api.client.util.BackOff;
 import com.google.api.client.util.ExponentialBackOff;
-import com.google.cloud.genomics.utils.GenomicsFactory;
 import com.google.common.base.Predicate;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Lists;
@@ -33,7 +33,7 @@
  * Includes complex retry logic to upon failure resume the stream at the last known good start
  * position without returning duplicate data.
  * 
- * TODO: refactor this further to simplify the generic signature. 
+ * TODO: refactor this further to simplify the generic signature.
  * 
  * @param <Request> Streaming request type.
  * @param <Response> Streaming response type.
@@ -43,12 +43,14 @@
 public abstract class GenomicsStreamIterator<Request, Response, Item, Stub extends io.grpc.stub.AbstractStub<Stub>>
     implements Iterator<Response> {
   private static final Logger LOG = Logger.getLogger(GenomicsStreamIterator.class.getName());
-  private final ExponentialBackOff backoff;
-  private final GenomicsChannel genomicsChannel;
-  private final Predicate<Item> shardPredicate;
+
+  protected final ManagedChannel genomicsChannel;
+  protected final Predicate<Item> shardPredicate;
   protected final Stub stub;
   protected final Request originalRequest;
 
+  protected ExponentialBackOff backoff;
+
   // Stateful members used to facilitate complex retry behavior for gRPC streams.
   private Iterator<Response> delegate;
   private Item lastSuccessfulDataItem;
@@ -57,20 +59,19 @@ public abstract class GenomicsStreamIterator<Request, Response, Item, Stub exten
   /**
    * Create a stream iterator that will filter shard data using the predicate, if supplied.
    * 
+   * @param channel The channel.
    * @param request The request for the shard of data.
-   * @param auth The OfflineAuth to use for the request.
    * @param fields Which fields to include in a partial response or null for all. NOT YET
    *        IMPLEMENTED.
-   * @param shardPredicate A predicate used to client-side filter results returned (e.g., enforce
-   *             a shard boundary and/or limit to SNPs only) or null for no filtering.
-   * @throws IOException
-   * @throws GeneralSecurityException
+   * @param shardPredicate A predicate used to client-side filter results returned (e.g., enforce a
+   *        shard boundary and/or limit to SNPs only) or null for no filtering.
    */
-  public GenomicsStreamIterator(Request request, GenomicsFactory.OfflineAuth auth, String fields,
-      Predicate<Item> shardPredicate) throws IOException, GeneralSecurityException {
+
+  protected GenomicsStreamIterator(ManagedChannel channel, Request request, String fields,
+      Predicate<Item> shardPredicate) {
     this.originalRequest = request;
     this.shardPredicate = shardPredicate;
-    genomicsChannel = GenomicsChannel.fromOfflineAuth(auth);
+    this.genomicsChannel = channel;
     stub = createStub(genomicsChannel);
 
     // Using default backoff settings. For details, see
@@ -83,7 +84,7 @@ public GenomicsStreamIterator(Request request, GenomicsFactory.OfflineAuth auth,
     idSentinel = null;
   }
 
-  abstract Stub createStub(GenomicsChannel genomicsChannel);
+  abstract Stub createStub(ManagedChannel genomicsChannel);
 
   abstract Iterator<Response> createIteratorFromStub(Request request);
 
@@ -168,6 +169,7 @@ private void setStreamStateForRetry() {
       // We have never returned any data. No need to set up state needed to filter previously
       // returned results.
       delegate = createIterator(originalRequest);
+      return;
     }
 
     if (getRequestStart(originalRequest) < getDataItemStart(lastSuccessfulDataItem)) {