Support for shutdown grace period in netty clients

spring-grpc-core/src/main/java/org/springframework/grpc/client/DefaultGrpcChannelFactory.java

@@ -16,10 +16,12 @@
 
 package org.springframework.grpc.client;
 
+import java.time.Duration;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.TimeUnit;
 
 import org.springframework.beans.factory.DisposableBean;
 
@@ -50,6 +52,8 @@ public class DefaultGrpcChannelFactory implements GrpcChannelFactory, Disposable
 
 	private VirtualTargets targets = VirtualTargets.DEFAULT;
 
+	private Duration shutdownGracePeriod;
+
 	public DefaultGrpcChannelFactory() {
 		this(List.of());
 	}
@@ -66,6 +70,10 @@ public void setCredentialsProvider(ChannelCredentialsProvider credentials) {
 		this.credentials = credentials;
 	}
 
+	public void setShutdownGracePeriod(Duration shutdownGracePeriod) {
+		this.shutdownGracePeriod = shutdownGracePeriod;
+	}
+
 	@Override
 	public ManagedChannelBuilder<?> createChannel(String authority) {
 		ManagedChannelBuilder<?> target = this.builders.computeIfAbsent(authority, path -> {
@@ -93,8 +101,20 @@ protected ManagedChannelBuilder<?> newChannel(String path, ChannelCredentials cr
 
 	@Override
 	public void destroy() {
+		long millis = this.shutdownGracePeriod.toMillis();
+
 		for (ManagedChannel channel : this.channels.values()) {
-			channel.shutdown();
+			try {
+				channel.shutdown();
+
+				if (!channel.awaitTermination(millis, TimeUnit.MILLISECONDS)) {
+					channel.shutdownNow();
+				}
+			}
+			catch (InterruptedException e) {
+				channel.shutdownNow();
+				Thread.currentThread().interrupt();
+			}
 		}
 	}
 

spring-grpc-spring-boot-autoconfigure/src/main/java/org/springframework/grpc/autoconfigure/client/GrpcClientAutoConfiguration.java

@@ -48,6 +48,9 @@ public DefaultGrpcChannelFactory defaultGrpcChannelFactory(final List<GrpcChanne
 		DefaultGrpcChannelFactory factory = new DefaultGrpcChannelFactory(configurers);
 		factory.setCredentialsProvider(credentials);
 		factory.setVirtualTargets(new NamedChannelVirtualTargets(channels));
+		// Take shutdownGracePeriod from the default channel since it is the same for all
+		// channels
+		factory.setShutdownGracePeriod(channels.getDefaultChannel().getShutdownGracePeriod());
 		return factory;
 	}
 

spring-grpc-spring-boot-autoconfigure/src/main/java/org/springframework/grpc/autoconfigure/client/GrpcClientProperties.java

@@ -221,6 +221,35 @@ public void setIdleTimeout(final Duration idleTimeout) {
 
 		// --------------------------------------------------
 
+		/**
+		 * Maximum time to wait for the client channels to gracefully shutdown. The
+		 * default is 30 seconds.
+		 */
+		@DurationUnit(ChronoUnit.SECONDS)
+		private Duration shutdownGracePeriod = Duration.ofSeconds(30);
+
+		/**
+		 * Gets the shutdown grace period.
+		 * @return The shutdown grace period.
+		 *
+		 * @see #setShutdownGracePeriod(Duration)
+		 */
+		public Duration getShutdownGracePeriod() {
+			return this.shutdownGracePeriod;
+		}
+
+		/**
+		 * The shutdown grace period.
+		 * @param shutdownGracePeriod shutdown grace period will client force shutdown
+		 * channels immediately
+		 *
+		 */
+		public void setShutdownGracePeriod(final Duration shutdownGracePeriod) {
+			this.shutdownGracePeriod = shutdownGracePeriod;
+		}
+
+		// --------------------------------------------------
+
 		@DurationUnit(ChronoUnit.SECONDS)
 		private Duration keepAliveTime;
 
@@ -431,6 +460,9 @@ public void copyDefaultsFrom(final NamedChannel config) {
 			if (this.address == null) {
 				this.address = config.address;
 			}
+			if (this.shutdownGracePeriod == null) {
+				this.shutdownGracePeriod = config.shutdownGracePeriod;
+			}
 			if (this.defaultLoadBalancingPolicy == null) {
 				this.defaultLoadBalancingPolicy = config.defaultLoadBalancingPolicy;
 			}