INT-1636 added 'target-user-expression' to the Twitter DM adapter

spring-integration-twitter/src/main/java/org/springframework/integration/twitter/config/TwitterOutboundChannelAdapterParser.java

@@ -18,10 +18,14 @@ package org.springframework.integration.twitter.config;
 
 import static org.springframework.integration.twitter.config.TwitterNamespaceHandler.BASE_PACKAGE;
 
+import org.springframework.beans.factory.config.BeanDefinition;
 import org.springframework.beans.factory.support.AbstractBeanDefinition;
 import org.springframework.beans.factory.support.BeanDefinitionBuilder;
+import org.springframework.beans.factory.support.RootBeanDefinition;
 import org.springframework.beans.factory.xml.ParserContext;
 import org.springframework.integration.config.xml.AbstractOutboundChannelAdapterParser;
+import org.springframework.util.StringUtils;
+
 import org.w3c.dom.Element;
 
 /**
@@ -38,6 +42,12 @@ public class TwitterOutboundChannelAdapterParser extends AbstractOutboundChannel
 		String className = determineClassName(element, parserContext);
 		BeanDefinitionBuilder builder = BeanDefinitionBuilder.rootBeanDefinition(className);
 		builder.addConstructorArgReference(element.getAttribute("twitter-template"));
+		String targetUserExpression = element.getAttribute("target-user-expression");
+		if (StringUtils.hasText(targetUserExpression)){
+			BeanDefinition expressionDef = new RootBeanDefinition("org.springframework.integration.config.ExpressionFactoryBean");
+			expressionDef.getConstructorArgumentValues().addGenericArgumentValue(targetUserExpression);
+			builder.addPropertyValue("targetUserExpression", expressionDef);
+		}
 		return builder.getBeanDefinition();
 	}
 
@@ -54,6 +64,7 @@ public class TwitterOutboundChannelAdapterParser extends AbstractOutboundChannel
 		else {
 			parserContext.getReaderContext().error("element '" + elementName + "' is not supported by this parser.", element);
 		}
+		
 		return className;
 	}
 

spring-integration-twitter/src/main/java/org/springframework/integration/twitter/outbound/DirectMessageSendingMessageHandler.java

@@ -16,6 +16,14 @@
 
 package org.springframework.integration.twitter.outbound;
 
+import org.springframework.beans.factory.BeanFactory;
+import org.springframework.context.expression.BeanFactoryResolver;
+import org.springframework.core.convert.ConversionService;
+import org.springframework.expression.Expression;
+import org.springframework.expression.ExpressionParser;
+import org.springframework.expression.spel.standard.SpelExpressionParser;
+import org.springframework.expression.spel.support.StandardEvaluationContext;
+import org.springframework.expression.spel.support.StandardTypeConverter;
 import org.springframework.integration.Message;
 import org.springframework.integration.handler.AbstractMessageHandler;
 import org.springframework.integration.twitter.core.TwitterHeaders;
@@ -32,6 +40,10 @@ import org.springframework.util.Assert;
 public class DirectMessageSendingMessageHandler extends AbstractMessageHandler {
 
 	private final TwitterOperations twitterOperations;
+	private final StandardEvaluationContext evaluationContext = new StandardEvaluationContext();
+	private static final ExpressionParser PARSER = new SpelExpressionParser();
+	
+	private volatile Expression targetUserExpression;
 
 
 	public DirectMessageSendingMessageHandler(TwitterOperations twitterOperations) {
@@ -39,14 +51,20 @@ public class DirectMessageSendingMessageHandler extends AbstractMessageHandler {
 		this.twitterOperations = twitterOperations;
 	}
 
+	public void setTargetUserExpression(Expression targetUserExpression) {
+		Assert.notNull(targetUserExpression, "'targetUserExpression' must not be null");
+		this.targetUserExpression = targetUserExpression;
+	}
 
 	@Override
 	protected void handleMessageInternal(Message<?> message) throws Exception {
 		Assert.isInstanceOf(String.class, message.getPayload(), "Only payload of type String is supported. If your payload " +
 				"is not of type String consider adding a transformer to the message flow in front of this adapter.");
-		Assert.isTrue(message.getHeaders().containsKey(TwitterHeaders.DM_TARGET_USER_ID), 
-				"the '" + TwitterHeaders.DM_TARGET_USER_ID + "' header is required");
-		Object toUser = message.getHeaders().get(TwitterHeaders.DM_TARGET_USER_ID);
+//		Assert.isTrue(message.getHeaders().containsKey(TwitterHeaders.DM_TARGET_USER_ID), 
+//				"the '" + TwitterHeaders.DM_TARGET_USER_ID + "' header is required");
+		
+		Object toUser = targetUserExpression.getValue(this.evaluationContext, message);
+		
 		Assert.isTrue(toUser instanceof String || toUser instanceof Integer,
 				"the header '" + TwitterHeaders.DM_TARGET_USER_ID + 
 				"' must be either a String (a screenname) or an int (a user ID)");
@@ -58,5 +76,22 @@ public class DirectMessageSendingMessageHandler extends AbstractMessageHandler {
 			this.twitterOperations.sendDirectMessage((String) toUser, payload);
 		}
 	}
+	
+	@Override
+	public void onInit() throws Exception{
+		super.onInit();
+		BeanFactory beanFactory = this.getBeanFactory();
+		if (beanFactory != null) {
+			this.evaluationContext.setBeanResolver(new BeanFactoryResolver(beanFactory));
+		}
+		ConversionService conversionService = this.getConversionService();
+		if (conversionService != null) {
+			this.evaluationContext.setTypeConverter(new StandardTypeConverter(conversionService));
+		}
+		if (targetUserExpression == null){
+			targetUserExpression = 
+				PARSER.parseExpression("headers[T(org.springframework.integration.twitter.core.TwitterHeaders).DM_TARGET_USER_ID]");
+		}
+	}
 
 }

spring-integration-twitter/src/main/resources/org/springframework/integration/twitter/config/spring-integration-twitter-2.0.xsd

@@ -94,7 +94,15 @@
 		</xsd:annotation>
 		<xsd:complexType>
 			<xsd:complexContent>
-				<xsd:extension base="outbound-twitter-type"/>
+				<xsd:extension base="outbound-twitter-type">
+					<xsd:attribute name="target-user-expression" use="optional">
+						<xsd:annotation>
+							<xsd:documentation>
+								Allows you to provide a valid SpEL Expression which will compute the target userid.
+							</xsd:documentation>
+						</xsd:annotation>	
+					</xsd:attribute>
+				</xsd:extension>
 			</xsd:complexContent>
 		</xsd:complexType>
 	</xsd:element>

spring-integration-twitter/src/test/java/org/springframework/integration/twitter/config/TestSendingMessageHandlerParser-context.xml

@@ -24,7 +24,10 @@
 	
    <channel id="inputChannel"/>
 
-	<twitter:dm-outbound-channel-adapter twitter-template="twitter" channel="inputChannel" />
+	<twitter:dm-outbound-channel-adapter id="dmAdapter"
+										 twitter-template="twitter" 
+								         channel="inputChannel" 
+								         target-user-expression="'z' + '_oleg'"/>
 	
 	<twitter:outbound-channel-adapter twitter-template="twitter" channel="inputChannel" />
    

spring-integration-twitter/src/test/java/org/springframework/integration/twitter/config/TestSendingMessageHandlerParserTests.java

@@ -16,8 +16,16 @@
 
 package org.springframework.integration.twitter.config;
 
+import static junit.framework.Assert.assertEquals;
+
 import org.junit.Test;
+
+import org.springframework.context.ApplicationContext;
 import org.springframework.context.support.ClassPathXmlApplicationContext;
+import org.springframework.expression.Expression;
+import org.springframework.integration.endpoint.EventDrivenConsumer;
+import org.springframework.integration.test.util.TestUtils;
+import org.springframework.integration.twitter.outbound.DirectMessageSendingMessageHandler;
 
 /**
  * @author Oleg Zhurakousky
@@ -27,8 +35,12 @@ public class TestSendingMessageHandlerParserTests {
 
 	@Test
 	public void testSendingMessageHandlerSuccessfulBootstrap(){
-		new ClassPathXmlApplicationContext("TestSendingMessageHandlerParser-context.xml", this.getClass());
-		// the fact that no exception was thrown satisfies this test	
+		ApplicationContext ac = new ClassPathXmlApplicationContext("TestSendingMessageHandlerParser-context.xml", this.getClass());
+		EventDrivenConsumer dmAdapter = ac.getBean("dmAdapter", EventDrivenConsumer.class);
+		DirectMessageSendingMessageHandler handler = 
+			(DirectMessageSendingMessageHandler) TestUtils.getPropertyValue(dmAdapter, "handler");
+		Expression targetUserExpression = (Expression) TestUtils.getPropertyValue(handler, "targetUserExpression");
+		assertEquals("'z' + '_oleg'", targetUserExpression.getExpressionString());
 	}
 
 }

spring-integration-twitter/src/test/java/org/springframework/integration/twitter/outbound/DirectMessageSendingMessageHandlerTests.java

@@ -23,6 +23,7 @@ import static org.mockito.Mockito.verify;
 import org.junit.Test;
 
 import org.springframework.integration.Message;
+import org.springframework.integration.config.ExpressionFactoryBean;
 import org.springframework.integration.support.MessageBuilder;
 import org.springframework.integration.twitter.core.TwitterHeaders;
 import org.springframework.integration.twitter.core.TwitterOperations;
@@ -47,5 +48,17 @@ public class DirectMessageSendingMessageHandlerTests {
 		handler.handleMessage(message2);
 		verify(twitter, times(1)).sendDirectMessage(123, "hello");
 	}
+	
+	@Test
+	public void validateSendDirectMessageWithTargetUserExpression() throws Exception{
+		Message<?> message1 = MessageBuilder.withPayload("hello").build();
+		DirectMessageSendingMessageHandler handler = new DirectMessageSendingMessageHandler(twitter);
+		ExpressionFactoryBean efb = new ExpressionFactoryBean("'z' + '_oleg'");
+		efb.afterPropertiesSet();
+		handler.setTargetUserExpression(efb.getObject());
+		handler.afterPropertiesSet();
+		handler.handleMessage(message1);
+		verify(twitter, times(1)).sendDirectMessage("z_oleg", "hello");
+	}
 
 }