Add BasicAuthenticationInterceptor for client

samples/grpc-tomcat-secure/src/test/java/org/springframework/grpc/sample/GrpcServerApplicationTests.java

@@ -3,8 +3,6 @@ package org.springframework.grpc.sample;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 
-import java.util.Base64;
-
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.junit.jupiter.api.Test;
@@ -18,20 +16,13 @@ import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Lazy;
 import org.springframework.grpc.client.ChannelBuilderOptions;
 import org.springframework.grpc.client.GrpcChannelFactory;
+import org.springframework.grpc.client.security.BasicAuthenticationInterceptor;
 import org.springframework.grpc.sample.proto.HelloReply;
 import org.springframework.grpc.sample.proto.HelloRequest;
 import org.springframework.grpc.sample.proto.SimpleGrpc;
-import org.springframework.grpc.server.security.GrpcSecurity;
-import org.springframework.grpc.test.LocalGrpcPort;
 import org.springframework.test.annotation.DirtiesContext;
 
-import io.grpc.CallOptions;
-import io.grpc.Channel;
-import io.grpc.ClientCall;
-import io.grpc.ClientInterceptor;
-import io.grpc.ForwardingClientCall.SimpleForwardingClientCall;
 import io.grpc.Status.Code;
-import io.grpc.MethodDescriptor;
 import io.grpc.StatusRuntimeException;
 
 @SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
@@ -79,22 +70,9 @@ public class GrpcServerApplicationTests {
 		@Lazy
 		SimpleGrpc.SimpleBlockingStub basic(GrpcChannelFactory channels, @LocalServerPort int port) {
 			return SimpleGrpc.newBlockingStub(channels.createChannel("0.0.0.0:" + port,
-					ChannelBuilderOptions.defaults().withCustomizer((__, channel) -> {
-						channel.intercept(new ClientInterceptor() {
-							@Override
-							public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(
-									MethodDescriptor<ReqT, RespT> method, CallOptions callOptions, Channel next) {
-								return new SimpleForwardingClientCall<ReqT, RespT>(next.newCall(method, callOptions)) {
-									public void start(ClientCall.Listener<RespT> responseListener,
-											io.grpc.Metadata headers) {
-										headers.put(GrpcSecurity.AUTHORIZATION_KEY,
-												"Basic " + Base64.getEncoder().encodeToString("user:user".getBytes()));
-										super.start(responseListener, headers);
-									};
-								};
-							}
-						});
-					})));
+					ChannelBuilderOptions.defaults()
+						.withCustomizer((authority, channel) -> channel
+							.intercept(new BasicAuthenticationInterceptor("user", "user")))));
 		}
 
 		@Bean

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

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2024-2024 the original author or authors.
+ *
+ * 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 org.springframework.grpc.client.security;
+
+import java.util.Base64;
+
+import org.springframework.grpc.server.security.GrpcSecurity;
+
+import io.grpc.CallOptions;
+import io.grpc.Channel;
+import io.grpc.ClientCall;
+import io.grpc.ClientInterceptor;
+import io.grpc.ForwardingClientCall.SimpleForwardingClientCall;
+import io.grpc.MethodDescriptor;
+
+/**
+ * An interceptor that adds basic authentication headers to gRPC client calls. This
+ * interceptor is used to authenticate gRPC client calls with a username and password. The
+ * username and password are encoded using Base64 and added to the Authorization header.
+ *
+ * @author Dave Syer
+ */
+public class BasicAuthenticationInterceptor implements ClientInterceptor {
+
+	private final String username;
+
+	private final String password;
+
+	public BasicAuthenticationInterceptor(String username, String password) {
+		this.username = username;
+		this.password = password;
+	}
+
+	@Override
+	public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(MethodDescriptor<ReqT, RespT> method,
+			CallOptions callOptions, Channel next) {
+		return new SimpleForwardingClientCall<ReqT, RespT>(next.newCall(method, callOptions)) {
+			public void start(ClientCall.Listener<RespT> responseListener, io.grpc.Metadata headers) {
+				headers.put(GrpcSecurity.AUTHORIZATION_KEY,
+						"Basic " + Base64.getEncoder()
+							.encodeToString((BasicAuthenticationInterceptor.this.username + ":"
+									+ BasicAuthenticationInterceptor.this.password)
+								.getBytes()));
+				super.start(responseListener, headers);
+			};
+		};
+	}
+
+}