Switch back to factory methods only.

Now that we are using ManagedChannel instead of ChannelImpl.

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

@@ -1,5 +1,7 @@
 package com.google.cloud.genomics.utils.grpc;
 
+import io.grpc.ManagedChannel;
+
 import java.io.FileNotFoundException;
 import java.util.Iterator;
 
@@ -34,7 +36,7 @@ public static void main(String[] args) throws Exception {
       return;
     }
 
-    GenomicsChannel channel = GenomicsChannel.fromOfflineAuth(auth);
+    ManagedChannel channel = GenomicsChannel.fromOfflineAuth(auth);
 
     // Regular RPC example: list all reference set assembly ids.
     ReferenceServiceV1BlockingStub refStub =

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

@@ -13,13 +13,9 @@
  */
 package com.google.cloud.genomics.utils.grpc;
 
-import io.grpc.CallOptions;
-import io.grpc.Channel;
-import io.grpc.ClientCall;
-import io.grpc.ClientInterceptors;
+import io.grpc.ClientInterceptor;
 import io.grpc.ManagedChannel;
 import io.grpc.Metadata;
-import io.grpc.MethodDescriptor;
 import io.grpc.auth.ClientAuthInterceptor;
 import io.grpc.netty.GrpcSslContexts;
 import io.grpc.netty.NegotiationType;
@@ -30,9 +26,9 @@
 import java.security.GeneralSecurityException;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 import java.util.concurrent.Executors;
-import java.util.concurrent.TimeUnit;
 
 import javax.net.ssl.SSLException;
 
@@ -42,19 +38,15 @@
 /**
  * A convenience class for creating gRPC channels to the Google Genomics API.
  */
-public class GenomicsChannel extends ManagedChannel {
+public class GenomicsChannel {
   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";
   // TODO https://github.com/googlegenomics/utils-java/issues/48
   private static final String PARTIAL_RESPONSE_HEADER = "X-Goog-FieldMask";
 
-  // NOTE: Unfortunately we need to keep a handle to both of these since Channel does not expose
-  // 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 {
+  private static ManagedChannel getGenomicsManagedChannel(List<ClientInterceptor> interceptors)
+      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();
@@ -67,110 +59,68 @@ 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())
+        .intercept(interceptors).build();
   }
 
-  private GenomicsChannel(String apiKey) throws SSLException {
-    managedChannel = getGenomicsManagedChannel();
+  /**
+   * Create a new gRPC channel to the Google Genomics API, using the provided api key for auth.
+   *
+   * @param apiKey the api key
+   * @return the ManagedChannel
+   * @throws SSLException
+   */
+  public static ManagedChannel fromApiKey(String apiKey) throws SSLException {
     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));
-  }
-
-  private GenomicsChannel(GoogleCredentials creds) throws SSLException {
-    managedChannel = getGenomicsManagedChannel();
-    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);
+    // TODO https://github.com/googlegenomics/utils-java/issues/48
+    return getGenomicsManagedChannel(Collections.singletonList(MetadataUtils
+        .newAttachHeadersInterceptor(headers)));
   }
 
   /**
-   * @throws InterruptedException
-   * @see io.grpc.ManagedChannel#shutdown()
-   * @see io.grpc.ManagedChannel#awaitTermination(long, TimeUnit)
+   * Create a new gRPC channel to the Google Genomics API, using the provided credentials for auth.
+   *
+   * @param creds the credential
+   * @return the ManagedChannel
+   * @throws SSLException
    */
-  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();
+  public static ManagedChannel fromCreds(GoogleCredentials creds) throws SSLException {
+    ClientInterceptor interceptor =
+        new ClientAuthInterceptor(creds.createScoped(Arrays.asList(GENOMICS_SCOPE)),
+            Executors.newSingleThreadExecutor());
+    // TODO https://github.com/googlegenomics/utils-java/issues/48
+    return getGenomicsManagedChannel(Collections.singletonList(interceptor));
   }
 
   /**
-   * Creates a new gRPC channel to the Google Genomics API, using the application default
-   * credentials for auth.
+   * Create a new gRPC channel to the Google Genomics API, using the application default credentials
+   * for auth.
+   *
+   * @return the ManagedChannel
+   * @throws SSLException
+   * @throws IOException
    */
-  public static GenomicsChannel fromDefaultCreds() throws IOException {
+  public static ManagedChannel fromDefaultCreds() throws SSLException, IOException {
     return fromCreds(GoogleCredentials.getApplicationDefault());
   }
 
   /**
-   * 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.
-   */
-  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.
+   * Create a new gRPC channel to the Google Genomics API, using OfflineAuth or the application
+   * default credentials.
    * 
    * This library works with both the older and newer support for OAuth2 clients.
    * 
    * 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.
+   * @param auth the OfflineAuth object
+   * @return the ManagedChannel
    * @throws IOException
    * @throws GeneralSecurityException
    */
-  public static GenomicsChannel fromOfflineAuth(GenomicsFactory.OfflineAuth auth)
+  public static ManagedChannel fromOfflineAuth(GenomicsFactory.OfflineAuth auth)
       throws IOException, GeneralSecurityException {
     if (auth.hasUserCredentials()) {
       return fromCreds(auth.getUserCredentials());

src/test/java/com/google/cloud/genomics/utils/grpc/FaultyGenomicsServerITCase.java

@@ -45,7 +45,7 @@ public class FaultyGenomicsServerITCase {
 
   protected static Server server;
   protected static IntegrationTestHelper helper;
-  protected static GenomicsChannel genomicsChannel;
+  protected static ManagedChannel genomicsChannel;
 
   // Variable accessed by both the InProcess Server executor threads and the test thread.
   protected static volatile double faultPercentage = 0.0;