GH-1014 Fix CustomRuntimeEventLoop to default to RoutingFunction

Resolves #1014

spring-cloud-function-adapters/spring-cloud-function-adapter-aws/src/main/java/org/springframework/cloud/function/adapter/aws/CustomRuntimeEventLoop.java

@@ -33,6 +33,7 @@ import org.apache.commons.logging.LogFactory;
 
 import org.springframework.cloud.function.context.FunctionCatalog;
 import org.springframework.cloud.function.context.catalog.SimpleFunctionRegistry.FunctionInvocationWrapper;
+import org.springframework.cloud.function.context.config.RoutingFunction;
 import org.springframework.cloud.function.json.JsonMapper;
 import org.springframework.context.ConfigurableApplicationContext;
 import org.springframework.context.SmartLifecycle;
@@ -218,7 +219,8 @@ public final class CustomRuntimeEventLoop implements SmartLifecycle {
 		return null;
 	}
 
-	private FunctionInvocationWrapper locateFunction(Environment environment, FunctionCatalog functionCatalog, HttpHeaders httpHeaders) {
+	private FunctionInvocationWrapper locateFunction(Environment environment, FunctionCatalog functionCatalog,
+			HttpHeaders httpHeaders) {
 		MediaType contentType = httpHeaders.getContentType();
 		String handlerName = environment.getProperty("DEFAULT_HANDLER");
 		if (logger.isDebugEnabled()) {
@@ -257,6 +259,15 @@ public final class CustomRuntimeEventLoop implements SmartLifecycle {
 			function = functionCatalog.lookup(handlerName, contentType.toString());
 		}
 
+		if (function == null) {
+			function = functionCatalog.lookup(RoutingFunction.FUNCTION_NAME, "application/json");
+			if (function != null && logger.isInfoEnabled()) {
+				logger.info("Will default to RoutingFunction, since multiple functions available in FunctionCatalog."
+								+ "Expecting 'spring.cloud.function.definition' or 'spring.cloud.function.routing-expression' as Message headers. "
+								+ "If invocation is over API Gateway, Message headers can be provided as HTTP headers.");
+			}
+		}
+
 		Assert.notNull(function, "Failed to locate function. Tried locating default function, "
 				+ "function by 'DEFAULT_HANDLER', '_HANDLER' env variable as well as'spring.cloud.function.definition'. "
 				+ "Functions available in catalog are: " + functionCatalog.getNames(null));

spring-cloud-function-samples/function-sample-aws-native/Dockerfile

@@ -40,7 +40,4 @@ RUN ln -s /usr/lib/gradle/bin/gradle /usr/bin/gradle
 
 ENV JAVA_HOME /usr/lib/graalvm
 
-ENTRYPOINT ["sh"]
+WORKDIR /function-sample-aws-native
-COPY . /home
-WORKDIR /home
-ENTRYPOINT ["sh"]

spring-cloud-function-samples/function-sample-aws-native/README.md

@@ -1,3 +1,9 @@
+# Introduction
+
+This example shows GraaalVM native spring-cloud-function application. The application itself is very simple and contains two functions - `uppercase` & `lowercase`.
+Unless specific value is specified as `handler`, the application will fall back on `RoutingFunction` where you can pass the routing instruction 
+via `spring.cloud.function.definition` Message header. If using API Gateway you can pass such header as HTTP header.
+
 # To run
 
 ## If you are on OSX Apple M1 Pro (arch64)
@@ -11,7 +17,7 @@ $ docker build -t "al2-graalvm19:native-uppercase" .
 Start the container
 
 ```
-$ docker run -dit al2-graalvm19:native-uppercase
+$ docker run -dit -v `pwd`:`pwd` -w `pwd` -v ~/.m2:/root/.m2 al2-graalvm19:native-uppercase
  ```
  
 Now navigate to the image terminal. Your working directory is alredy set for the root of the project. You can verify it by executing `ls`.

spring-cloud-function-samples/function-sample-aws-native/pom.xml

@@ -148,5 +148,40 @@
 			</plugin>
 		</plugins>
 	</build>
+	
+	<repositories>
+		<repository>
+			<id>spring-snapshots</id>
+			<name>Spring Snapshots</name>
+			<url>https://repo.spring.io/snapshot</url>
+		</repository>
+		<repository>
+			<id>spring-milestones</id>
+			<name>Spring Milestones</name>
+			<url>https://repo.spring.io/milestone</url>
+		</repository>
+		<repository>
+			<id>spring-releases</id>
+			<name>Spring Releases</name>
+			<url>https://repo.spring.io/release</url>
+		</repository>
+	</repositories>
+	<pluginRepositories>
+		<pluginRepository>
+			<id>spring-snapshots</id>
+			<name>Spring Snapshots</name>
+			<url>https://repo.spring.io/snapshot</url>
+		</pluginRepository>
+		<pluginRepository>
+			<id>spring-milestones</id>
+			<name>Spring Milestones</name>
+			<url>https://repo.spring.io/milestone</url>
+		</pluginRepository>
+		<pluginRepository>
+			<id>spring-releases</id>
+			<name>Spring Releases</name>
+			<url>https://repo.spring.io/release</url>
+		</pluginRepository>
+	</pluginRepositories>
 
 </project>

spring-cloud-function-samples/function-sample-aws-native/src/assembly/native.xml

@@ -22,7 +22,7 @@
 			<useDefaultExcludes>true</useDefaultExcludes>
 			<fileMode>0775</fileMode>
 			<includes>
-				<include>native-uppercase</include>
+				<include>function-sample-aws-native</include>
 			</includes>
 		</fileSet>
 	</fileSets>

spring-cloud-function-samples/function-sample-aws-native/src/main/java/com/example/demo/NativeUppercaseApplication.java

@@ -2,17 +2,35 @@ package com.example.demo;
 
 import java.util.function.Function;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.cloud.function.context.DefaultMessageRoutingHandler;
+import org.springframework.cloud.function.context.MessageRoutingCallback;
 import org.springframework.context.annotation.Bean;
+import org.springframework.messaging.Message;
 
 @SpringBootApplication
 public class NativeUppercaseApplication {
 
+	Log logger = LogFactory.getLog(NativeUppercaseApplication.class);
+
 	public static void main(String[] args) {
 		SpringApplication.run(NativeUppercaseApplication.class, args);
 	}
-	
+
+	@Bean
+	public MessageRoutingCallback customRouter() {
+		return new MessageRoutingCallback() {
+			@Override
+			public String routingResult(Message<?> message) {
+				logger.info("Received message: " + message);
+				return (String) message.getHeaders().get("spring.cloud.function.definition");
+			}
+		};
+	}
+
 	@Bean
 	public Function<String, String> uppercase() {
 		return v -> {
@@ -21,4 +39,12 @@ public class NativeUppercaseApplication {
 		};
 	}
 
+	@Bean
+	public Function<String, String> lowercase() {
+		return v -> {
+			System.out.println("Lowercasing " + v);
+			return v.toUpperCase();
+		};
+	}
+
 }

spring-cloud-function-samples/function-sample-aws-native/src/shell/native/bootstrap

@@ -2,4 +2,4 @@
 
 cd ${LAMBDA_TASK_ROOT:-.}
 
-./native-uppercase -Dlogging.level.org.springframework=DEBUG
+./function-sample-aws-native -Dlogging.level.org.springframework=DEBUG

spring-cloud-function-samples/function-sample-cloudevent-rsocket/src/test/java/io/spring/cloudevent/DemoApplicationTests.java

@@ -21,7 +21,7 @@ import org.springframework.messaging.rsocket.RSocketRequester;
 import org.springframework.util.MimeTypeUtils;
 
 
-@SpringBootTest(properties = {"spring.rsocket.server.port=55555"})
+@SpringBootTest(properties = {"spring.rsocket.server.port=55551"})
 @ExtendWith(DemoApplicationTests.TestRule.class)
 public class DemoApplicationTests {
 
@@ -44,7 +44,7 @@ public class DemoApplicationTests {
 				"    }\n" +
 				"}";
 
-		this.rsocketRequesterBuilder.tcp("localhost", 55555)
+		this.rsocketRequesterBuilder.tcp("localhost", 55551)
 			.route("hire")
 			.metadata("{\"content-type\":\"application/cloudevents+json\"}", MimeTypeUtils.APPLICATION_JSON)
 			.data(payload)

spring-cloud-function-samples/function-sample-cloudevent-stream/pom.xml

@@ -28,7 +28,7 @@
 		 <dependency>
             <groupId>org.springframework.cloud</groupId>
             <artifactId>spring-cloud-stream</artifactId>
-            <version>4.0.0-SNAPSHOT</version>
+            <version>4.0.2-SNAPSHOT</version>
         </dependency>
         <!-- RabbitMQ - only needed if you intend to invoke via RabbitMQ -->
         <dependency>

spring-cloud-function-samples/function-sample-cloudevent-stream/src/main/resources/application.properties

@@ -1,3 +0,0 @@
-spring.cloud.function.definition=hire
-spring.cloud.stream.bindings.hire-in-0.binder=rabbit
-spring.cloud.stream.bindings.hire-out-0.binder=kafka

spring-cloud-function-samples/function-sample-cloudevent-stream/src/main/resources/application.yaml

@@ -0,0 +1,15 @@
+spring:
+  cloud:
+    stream:
+      bindings:
+        hire-in-0:
+          binder: rabbit1
+        hire-out-0:
+          binder: kafka1
+      binders:
+        rabbit1:
+          type: rabbit
+        kafka1:
+          type: kafka
+    function:
+      definition: hire