spring-projectsGH-3869: Create The Context Holder Request Handler Advice.

spring-projectsGH-3869: Add unit tests.

spring-projectsGH-3869: Create Advice.

spring-projectsGH-3869: Correct typo.

Author: adel-haidar

spring-integration-file/src/main/java/org/springframework/integration/file/remote/session/ContextHolderRequestHandlerAdvice.java

@@ -0,0 +1,86 @@
+/*
+ * Copyright 2015-2022 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.integration.file.remote.session;
+
+import java.util.function.Consumer;
+import java.util.function.Function;
+
+import org.springframework.messaging.Message;
+
+/**
+ * Provides a key for the context holder.This key could for example be stored in a message header.
+ *
+ * @author Adel Haidar
+ * @since 6.0
+ */
+public class ContextHolderRequestHandlerAdvice {
+	public Function<Message<?>, Object> keyProvider;
+
+	public Consumer<Object> contextSetHook;
+
+	public Consumer<Object> contextClearHook;
+
+	/**
+	 * Returns the key provider function.
+	 * @return The key provider function.
+	 *
+	 */
+	public Function<Message<?>, Object> getKeyProvider() {
+		return this.keyProvider;
+	}
+
+	/**
+	 * Sets the key provider function.
+	 * @param keyProvider the key provider.
+	 */
+	public void setKeyProvider(Function<Message<?>, Object> keyProvider) {
+		this.keyProvider = keyProvider;
+	}
+
+	/**
+	 * Returns the context set hook function.
+	 * @return The context set hook function.
+	 *
+	 */
+	public Consumer<Object> getContextSetHook() {
+		return this.contextSetHook;
+	}
+
+	/**
+	 * Sets the context set hook function.
+	 * @param contextSetHook the context set hook function.
+	 */
+	public void setContextSetHook(Consumer<Object> contextSetHook) {
+		this.contextSetHook = contextSetHook;
+	}
+
+	/**
+	 * Returns the context clear hook function.
+	 * @return The context clear hook function.
+	 */
+	public Consumer<Object> getContextClearHook() {
+		return this.contextClearHook;
+	}
+
+	/**
+	 * Sets the context clear hook function.
+	 * @param contextClearHook the context clear hook function.
+	 */
+	public void setContextClearHook(Consumer<Object> contextClearHook) {
+		this.contextClearHook = contextClearHook;
+	}
+}

spring-integration-file/src/main/java/org/springframework/integration/file/remote/session/DelegatingSessionFactory.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2021 the original author or authors.
+ * Copyright 2015-2022 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.
@@ -52,7 +52,7 @@ public DelegatingSessionFactory(Map<Object, SessionFactory<F>> factories, Sessio
 	 * @param factoryLocator the factory.
 	 */
 	public DelegatingSessionFactory(SessionFactoryLocator<F> factoryLocator) {
-		Assert.notNull(factoryLocator, "'factoryFactory' cannot be null");
+		Assert.notNull(factoryLocator, "'factoryLocator' cannot be null");
 		this.factoryLocator = factoryLocator;
 	}
 

spring-integration-file/src/test/java/org/springframework/integration/file/remote/session/ContextHolderRequestHandlerAdviceTests.java

@@ -0,0 +1,103 @@
+/*
+ * Copyright 2013-2022 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.integration.file.remote.session;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import org.springframework.integration.support.MessageBuilder;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.mock;
+
+public class ContextHolderRequestHandlerAdviceTests {
+
+	private ContextHolderRequestHandlerAdvice advice;
+
+	@BeforeEach
+	public void setUp() {
+		advice = new ContextHolderRequestHandlerAdvice();
+	}
+
+	@Test
+	public void shouldSetKeyProvider() {
+		// given
+		advice.setKeyProvider(message -> message.getHeaders().get("test-key"));
+		final var message = MessageBuilder.withPayload("test-payload").setHeader("test-key", new TestSessionFactory()).build();
+
+		// when
+		final var sessionFactory = advice.getKeyProvider().apply(message);
+
+		// then
+		assertThat(sessionFactory).isNotNull();
+		assertThat(sessionFactory).isInstanceOf(TestSessionFactory.class);
+	}
+
+	@Test
+	void shouldSetContextSetHook() {
+		// given
+		final Map<Object, SessionFactory<String>> factories = new HashMap<>();
+		final var testSessionFactory = new TestSessionFactory();
+		factories.put("test-key", testSessionFactory);
+		final var defaultFactory = new TestSessionFactory();
+		factories.put("default", defaultFactory);
+
+		final DelegatingSessionFactory<String> delegatingSessionFactory = new DelegatingSessionFactory<>(factories, testSessionFactory);
+		advice.setContextSetHook(delegatingSessionFactory::setThreadKey);
+
+		// when
+		advice.getContextSetHook().accept("test-key");
+
+		// then
+		assertThat(delegatingSessionFactory.getSession()).isNotEqualTo(defaultFactory.mockSession).isEqualTo(testSessionFactory.mockSession);
+	}
+
+	@Test
+	void shouldSetContextClearHook() {
+		// given
+		final Map<Object, SessionFactory<String>> factories = new HashMap<>();
+		final var testSessionFactory = new TestSessionFactory();
+		factories.put("test-key", testSessionFactory);
+		final var defaultFactory = new TestSessionFactory();
+		factories.put("default", defaultFactory);
+
+		final DelegatingSessionFactory<String> delegatingSessionFactory = new DelegatingSessionFactory<>(factories, defaultFactory);
+		advice.setContextClearHook(key -> delegatingSessionFactory.clearThreadKey());
+
+		// when
+		advice.getContextClearHook().accept("test-key");
+
+		// then
+		assertThat(delegatingSessionFactory.getSession()).isNotEqualTo(testSessionFactory.mockSession).isEqualTo(defaultFactory.mockSession);
+	}
+
+	private static class TestSessionFactory implements SessionFactory<String> {
+
+		@SuppressWarnings("unchecked")
+		private final Session<String> mockSession = mock(Session.class);
+
+		@Override
+		public Session<String> getSession() {
+			return this.mockSession;
+		}
+
+	}
+
+}