fix: Make Java gRPC client use timeouts as expected

java/serving-client/src/main/java/dev/feast/FeastClient.java

@@ -26,7 +26,6 @@
 import feast.proto.serving.ServingServiceGrpc.ServingServiceBlockingStub;
 import feast.proto.types.ValueProto;
 import io.grpc.CallCredentials;
-import io.grpc.Deadline;
 import io.grpc.ManagedChannel;
 import io.grpc.ManagedChannelBuilder;
 import io.grpc.netty.shaded.io.grpc.netty.GrpcSslContexts;
@@ -50,6 +49,7 @@ public class FeastClient implements AutoCloseable {
 
   private final ManagedChannel channel;
   private final ServingServiceBlockingStub stub;
+  private final long requestTimeout;
 
   /**
    * Create a client to access Feast Serving.
@@ -68,12 +68,14 @@ public static FeastClient create(String host, int port) {
    *
    * @param host hostname or ip address of Feast serving GRPC server
    * @param port port number of Feast serving GRPC server
-   * @param deadline GRPC deadline of Feast serving GRPC server {@link Deadline}
+   * @param requestTimeout maximum duration for online retrievals from the GRPC server in
+   *     milliseconds, use 0 for no timeout
    * @return {@link FeastClient}
    */
-  public static FeastClient create(String host, int port, Deadline deadline) {
+  public static FeastClient create(String host, int port, long requestTimeout) {
     // configure client with no security config.
-    return FeastClient.createSecure(host, port, SecurityConfig.newBuilder().build(), deadline);
+    return FeastClient.createSecure(
+        host, port, SecurityConfig.newBuilder().build(), requestTimeout);
   }
 
   /**
@@ -86,7 +88,7 @@ public static FeastClient create(String host, int port, Deadline deadline) {
    * @return {@link FeastClient}
    */
   public static FeastClient createSecure(String host, int port, SecurityConfig securityConfig) {
-    return createSecure(host, port, securityConfig, null);
+    return FeastClient.createSecure(host, port, securityConfig, 0);
   }
 
   /**
@@ -96,11 +98,17 @@ public static FeastClient createSecure(String host, int port, SecurityConfig sec
    * @param port port number of Feast serving GRPC server
    * @param securityConfig security options to configure the Feast client. See {@link
    *     SecurityConfig} for options.
-   * @param deadline GRPC deadline of Feast serving GRPC server {@link Deadline}
+   * @param requestTimeout maximum duration for online retrievals from the GRPC server in
+   *     milliseconds
    * @return {@link FeastClient}
    */
   public static FeastClient createSecure(
-      String host, int port, SecurityConfig securityConfig, Deadline deadline) {
+      String host, int port, SecurityConfig securityConfig, long requestTimeout) {
+
+    if (requestTimeout < 0) {
+      throw new IllegalArgumentException("Request timeout can't be negative");
+    }
+
     // Configure client TLS
     ManagedChannel channel = null;
     if (securityConfig.isTLSEnabled()) {
@@ -127,7 +135,7 @@ public static FeastClient createSecure(
       channel = ManagedChannelBuilder.forAddress(host, port).usePlaintext().build();
     }
 
-    return new FeastClient(channel, securityConfig.getCredentials(), Optional.ofNullable(deadline));
+    return new FeastClient(channel, securityConfig.getCredentials(), requestTimeout);
   }
 
   /**
@@ -158,7 +166,10 @@ public List<Row> getOnlineFeatures(List<String> featureRefs, List<Row> entities)
 
     requestBuilder.putAllEntities(getEntityValuesMap(entities));
 
-    GetOnlineFeaturesResponse response = stub.getOnlineFeatures(requestBuilder.build());
+    ServingServiceGrpc.ServingServiceBlockingStub timedStub =
+        requestTimeout != 0 ? stub.withDeadlineAfter(requestTimeout, TimeUnit.MILLISECONDS) : stub;
+
+    GetOnlineFeaturesResponse response = timedStub.getOnlineFeatures(requestBuilder.build());
 
     List<Row> results = Lists.newArrayList();
     if (response.getResultsCount() == 0) {
@@ -231,12 +242,13 @@ public List<Row> getOnlineFeatures(List<String> featureRefs, List<Row> rows, Str
   }
 
   protected FeastClient(ManagedChannel channel, Optional<CallCredentials> credentials) {
-    this(channel, credentials, Optional.empty());
+    this(channel, credentials, 0);
   }
 
   protected FeastClient(
-      ManagedChannel channel, Optional<CallCredentials> credentials, Optional<Deadline> deadline) {
+      ManagedChannel channel, Optional<CallCredentials> credentials, long requestTimeout) {
     this.channel = channel;
+    this.requestTimeout = requestTimeout;
     TracingClientInterceptor tracingInterceptor =
         TracingClientInterceptor.newBuilder().withTracer(GlobalTracer.get()).build();
 
@@ -247,10 +259,6 @@ protected FeastClient(
       servingStub = servingStub.withCallCredentials(credentials.get());
     }
 
-    if (deadline.isPresent()) {
-      servingStub = servingStub.withDeadline(deadline.get());
-    }
-
     this.stub = servingStub;
   }
 

java/serving-client/src/test/java/dev/feast/FeastClientTest.java

@@ -38,15 +38,14 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Optional;
-import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
 import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
 
 public class FeastClientTest {
   private final String AUTH_TOKEN = "test token";
-  private final Deadline DEADLINE = Deadline.after(2, TimeUnit.SECONDS);
+  private final long TIMEOUT_MILLIS = 300;
 
   @Rule public GrpcCleanupRule grpcRule;
   private AtomicBoolean isAuthenticated;
@@ -88,7 +87,7 @@ public void setup() throws Exception {
     ManagedChannel channel =
         this.grpcRule.register(
             InProcessChannelBuilder.forName(serverName).directExecutor().build());
-    this.client = new FeastClient(channel, Optional.empty(), Optional.of(DEADLINE));
+    this.client = new FeastClient(channel, Optional.empty(), TIMEOUT_MILLIS);
   }
 
   @Test