Add support for detecting FunctionRegistration or Function

User can now provide a Function or an ApplicationInitializer. Also
the initializer can create a FunctionRegistration with the handler
name instead of a bean with the handler name. Better control of
input and output types that way.

Fixes gh-231

spring-cloud-function-deployer/src/it/flux/pom.xml

@@ -5,7 +5,7 @@
 
 	<groupId>com.example</groupId>
 	<artifactId>flux-sample</artifactId>
-	<version>1.0.0.M1</version>
+	<version>1.0.0.RC1</version>
 	<packaging>jar</packaging>
 
 	<parent>
@@ -18,7 +18,7 @@
 	<properties>
 		<java.version>1.8</java.version>
 		<spring-cloud-function.version>2.0.0.BUILD-SNAPSHOT</spring-cloud-function.version>
-		<wrapper.version>1.0.15.RELEASE</wrapper.version>
+		<wrapper.version>1.0.17.RELEASE</wrapper.version>
 	</properties>
 
 	<dependencies>

spring-cloud-function-deployer/src/it/support/pom.xml

@@ -18,7 +18,7 @@
 	<properties>
 		<java.version>1.8</java.version>
 		<spring-cloud-function.version>2.0.0.BUILD-SNAPSHOT</spring-cloud-function.version>
-		<wrapper.version>1.0.12.RELEASE</wrapper.version>
+		<wrapper.version>1.0.17.RELEASE</wrapper.version>
 	</properties>
 
 	<dependencies>

spring-cloud-function-deployer/src/main/java/org/springframework/cloud/function/deployer/ContextRunner.java

@@ -18,13 +18,10 @@ package org.springframework.cloud.function.deployer;
 
 import java.lang.reflect.Field;
 import java.net.URL;
-import java.util.Collections;
 import java.util.Map;
 
-import org.springframework.beans.BeanUtils;
 import org.springframework.boot.SpringApplication;
-import org.springframework.context.ApplicationContext;
-import org.springframework.context.ApplicationContextInitializer;
+import org.springframework.cloud.function.context.FunctionalSpringApplication;
 import org.springframework.context.ConfigurableApplicationContext;
 import org.springframework.core.env.MapPropertySource;
 import org.springframework.core.env.StandardEnvironment;
@@ -59,16 +56,7 @@ public class ContextRunner {
 							new MapPropertySource("appDeployer", properties));
 					running = true;
 					Class<?> sourceClass = ClassUtils.resolveClassName(source, null);
-					ApplicationContextInitializer<?> initializer = null;
-					if (ApplicationContextInitializer.class.isAssignableFrom(sourceClass)) {
-						initializer = BeanUtils.instantiateClass(sourceClass, ApplicationContextInitializer.class);
-						sourceClass = Dummy.class;
-					}
 					SpringApplication builder = builder(sourceClass);
-					if (initializer!=null) {
-						builder.addInitializers(initializer);
-						builder.setDefaultProperties(Collections.singletonMap("spring.functional.enabled", "true"));
-					}
 					builder.setEnvironment(environment);
 					builder.setRegisterShutdownHook(false);
 					context = builder.run(args);
@@ -131,19 +119,8 @@ public class ContextRunner {
 	}
 
 	private static SpringApplication builder(Class<?> type) {
-		if (type==Dummy.class) {
-			SpringApplication application = new SpringApplication() {
-				@Override
-				protected void load(ApplicationContext context, Object[] sources) {
-				}
-			};
-			// Boot doesn't allow null sources
-			application.setSources(Collections.singleton(Dummy.class.getName()));
-			return application;
-		}
-		return new SpringApplication(type);
+		SpringApplication application = new FunctionalSpringApplication(type);
+		return application;
 	}
-	
-	private class Dummy {}
 
 }

spring-cloud-function-deployer/src/main/java/org/springframework/cloud/function/deployer/FunctionCreatorConfiguration.java

@@ -51,10 +51,12 @@ import org.springframework.boot.loader.archive.Archive;
 import org.springframework.boot.loader.archive.ExplodedArchive;
 import org.springframework.boot.loader.archive.JarFileArchive;
 import org.springframework.cloud.deployer.resource.support.DelegatingResourceLoader;
+import org.springframework.cloud.function.context.FunctionCatalog;
 import org.springframework.cloud.function.context.FunctionRegistration;
 import org.springframework.cloud.function.context.FunctionRegistry;
 import org.springframework.cloud.function.context.FunctionType;
 import org.springframework.cloud.function.context.catalog.FunctionInspector;
+import org.springframework.cloud.function.core.FluxFunction;
 import org.springframework.context.ConfigurableApplicationContext;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.env.Environment;
@@ -381,6 +383,32 @@ class FunctionCreatorConfiguration {
 				Object result = null;
 				if (this.runner != null) {
 					result = this.runner.getBean(type);
+					if (result == null) {
+						if (this.runner.containsBean(FunctionCatalog.class.getName())) {
+							Object catalog = this.runner
+									.getBean(FunctionCatalog.class.getName());
+							result = this.runner.evaluate("lookup(#function).getTarget()",
+									catalog, "function", type);
+							if (result != null) {
+								logger.info("Located registration: " + type + " of type "
+										+ result.getClass());
+							}
+						}
+					}
+					else {
+						logger.info("Located bean: " + type + " of type "
+								+ result.getClass());
+						if (result.getClass().getName()
+								.equals(FunctionRegistration.class.getName())) {
+							result = this.runner.evaluate("getTarget()", result);
+						}
+					}
+					if (result != null) {
+						if (result.getClass().getName()
+								.equals(FluxFunction.class.getName())) {
+							result = this.runner.evaluate("getTarget()", result);
+						}
+					}
 				}
 				if (result == null) {
 					logger.info("No bean found. Instantiating: " + type);
@@ -390,7 +418,6 @@ class FunctionCreatorConfiguration {
 					}
 				}
 				if (result != null) {
-					logger.info("Located bean: " + type);
 					return result;
 				}
 				throw new IllegalStateException("Cannot create bean for: " + type);

spring-cloud-function-deployer/src/test/java/org/springframework/cloud/function/deployer/FunctionCreatorConfigurationTests.java

@@ -21,7 +21,6 @@ import java.util.function.Supplier;
 
 import org.junit.Assume;
 import org.junit.BeforeClass;
-import org.junit.Ignore;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -97,13 +96,45 @@ public abstract class FunctionCreatorConfigurationTests {
 	@EnableAutoConfiguration
 	@TestPropertySource(properties = {
 			"function.location=app:classpath,file:target/test-classes,file:target/test-classes/app",
-			"function.bean=myDoubler",
+			"function.bean=doubler",
 			"function.main=org.springframework.cloud.function.test.FunctionRegistrar" })
 	public static class SingleFunctionWithRegistrarTests
 			extends FunctionCreatorConfigurationTests {
 
 		@Test
-		@Ignore // related to boot 2.1 no bean override change
+		public void testDouble() {
+			Function<Flux<Integer>, Flux<Integer>> function = catalog
+					.lookup(Function.class, "function0");
+			assertThat(function.apply(Flux.just(2)).blockFirst()).isEqualTo(4);
+		}
+
+	}
+
+	@EnableAutoConfiguration
+	@TestPropertySource(properties = {
+			"function.location=app:classpath,file:target/test-classes,file:target/test-classes/app",
+			"function.bean=frenchizer",
+			"function.main=org.springframework.cloud.function.test.FunctionRegistrar" })
+	public static class SingleFunctionWithRegistrarAndRegistrationTests
+			extends FunctionCreatorConfigurationTests {
+
+		@Test
+		public void testFrenchize() {
+			Function<Flux<Integer>, Flux<String>> function = catalog
+					.lookup(Function.class, "function0");
+			assertThat(function.apply(Flux.just(2)).blockFirst()).isEqualTo("deux");
+		}
+	}
+
+	@EnableAutoConfiguration
+	@TestPropertySource(properties = {
+			"function.location=app:classpath,file:target/test-classes,file:target/test-classes/app",
+			"function.bean=myDoubler",
+			"function.main=org.springframework.cloud.function.test.FunctionInitializer" })
+	public static class SingleFunctionWithInitializerTests
+			extends FunctionCreatorConfigurationTests {
+
+		@Test
 		public void testDouble() {
 			Function<Flux<Integer>, Flux<Integer>> function = catalog
 					.lookup(Function.class, "function0");

spring-cloud-function-deployer/src/test/java/org/springframework/cloud/function/test/FunctionInitializer.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2017 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
+ *
+ *      http://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.cloud.function.test;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.cloud.function.context.FunctionalSpringApplication;
+import org.springframework.context.ApplicationContextInitializer;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.support.GenericApplicationContext;
+
+/**
+ * @author Dave Syer
+ */
+public class FunctionInitializer
+		implements ApplicationContextInitializer<GenericApplicationContext> {
+
+	@Bean
+	public Doubler myDoubler() {
+		return new Doubler();
+	}
+
+	@Bean
+	public Frenchizer myFrenchizer() {
+		return new Frenchizer();
+	}
+
+	public static void main(String[] args) throws Exception {
+		SpringApplication application = new FunctionalSpringApplication(
+				FunctionInitializer.class);
+		application.run(args);
+	}
+
+	@Override
+	public void initialize(GenericApplicationContext context) {
+		// TODO: support for FunctionRegistration
+		context.registerBean("myDoubler", Doubler.class, () -> myDoubler());
+		context.registerBean("myFrenchizer", Frenchizer.class, () -> myFrenchizer());
+	}
+}

spring-cloud-function-deployer/src/test/java/org/springframework/cloud/function/test/FunctionRegistrar.java

@@ -16,10 +16,10 @@
 
 package org.springframework.cloud.function.test;
 
-import java.util.Collections;
-
 import org.springframework.boot.SpringApplication;
-import org.springframework.context.ApplicationContext;
+import org.springframework.cloud.function.context.FunctionRegistration;
+import org.springframework.cloud.function.context.FunctionType;
+import org.springframework.cloud.function.context.FunctionalSpringApplication;
 import org.springframework.context.ApplicationContextInitializer;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.support.GenericApplicationContext;
@@ -41,21 +41,21 @@ public class FunctionRegistrar
 	}
 
 	public static void main(String[] args) throws Exception {
-		SpringApplication application = new SpringApplication(Object.class) {
-			@Override
-			protected void load(ApplicationContext context, Object[] sources) {
-			}
-		};
-		application.addInitializers(new FunctionRegistrar());
-		application.setDefaultProperties(
-				Collections.singletonMap("spring.functional.enabled", "true"));
+		SpringApplication application = new FunctionalSpringApplication(
+				FunctionRegistrar.class);
 		application.run(args);
 	}
 
 	@Override
 	public void initialize(GenericApplicationContext context) {
-		// TODO: support for FunctionRegistration
-		context.registerBean("myDoubler", Doubler.class, () -> myDoubler());
-		context.registerBean("myFrenchizer", Frenchizer.class, () -> myFrenchizer());
+		context.registerBean("theDoubler", FunctionRegistration.class,
+				() -> new FunctionRegistration<>(myDoubler(), "doubler")
+						.type(FunctionType.of((Doubler.class))));
+		context.registerBean("frenchizer", FunctionRegistration.class, () -> {
+			Frenchizer function = myFrenchizer();
+			function.init();
+			return new FunctionRegistration<>(function, "theFrenchizer")
+					.type(FunctionType.of((Frenchizer.class)));
+		});
 	}
 }

spring-cloud-function-web/src/main/java/org/springframework/cloud/function/web/RequestProcessor.java

@@ -16,10 +16,13 @@
 
 package org.springframework.cloud.function.web;
 
+import java.lang.reflect.Method;
 import java.lang.reflect.ParameterizedType;
 import java.lang.reflect.Type;
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
@@ -38,15 +41,29 @@ import org.springframework.cloud.function.context.message.MessageUtils;
 import org.springframework.cloud.function.core.FluxWrapper;
 import org.springframework.cloud.function.json.JsonMapper;
 import org.springframework.cloud.function.web.util.HeaderUtils;
+import org.springframework.core.MethodParameter;
+import org.springframework.core.ReactiveAdapter;
+import org.springframework.core.ReactiveAdapterRegistry;
 import org.springframework.core.ResolvableType;
+import org.springframework.core.codec.DecodingException;
+import org.springframework.core.codec.Hints;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
 import org.springframework.http.ResponseEntity;
 import org.springframework.http.ResponseEntity.BodyBuilder;
+import org.springframework.http.codec.HttpMessageReader;
+import org.springframework.http.codec.ServerCodecConfigurer;
+import org.springframework.http.server.reactive.ServerHttpRequest;
+import org.springframework.http.server.reactive.ServerHttpResponse;
 import org.springframework.messaging.Message;
 import org.springframework.util.LinkedMultiValueMap;
 import org.springframework.util.MultiValueMap;
+import org.springframework.util.ReflectionUtils;
 import org.springframework.util.StringUtils;
+import org.springframework.web.server.ServerWebExchange;
+import org.springframework.web.server.ServerWebInputException;
+import org.springframework.web.server.UnsupportedMediaTypeStatusException;
 
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
@@ -65,11 +82,16 @@ public class RequestProcessor {
 
 	private final JsonMapper mapper;
 
-	public RequestProcessor(FunctionInspector inspector, ObjectProvider<JsonMapper> mapper,
-			StringConverter converter) {
+	private final List<HttpMessageReader<?>> messageReaders;
+
+	public RequestProcessor(FunctionInspector inspector,
+			ObjectProvider<JsonMapper> mapper, StringConverter converter,
+			ObjectProvider<ServerCodecConfigurer> codecs) {
 		this.mapper = mapper.getIfAvailable();
 		this.inspector = inspector;
 		this.converter = converter;
+		ServerCodecConfigurer source = codecs.getIfAvailable();
+		this.messageReaders = source == null ? null : source.getReaders();
 	}
 
 	public static FunctionWrapper wrapper(
@@ -95,6 +117,12 @@ public class RequestProcessor {
 		}
 	}
 
+	public Mono<ResponseEntity<?>> post(FunctionWrapper wrapper,
+			ServerWebExchange exchange) {
+		return Mono.from(body(wrapper.handler(), exchange))
+				.flatMap(body -> response(wrapper, body, false));
+	}
+
 	public Mono<ResponseEntity<?>> post(FunctionWrapper wrapper, String body,
 			boolean stream) {
 		Object function = wrapper.handler();
@@ -102,12 +130,15 @@ public class RequestProcessor {
 		Type itemType = getItemType(function);
 
 		Object input = body;
-		if (StringUtils.hasText(body) && this.mapper!=null) {
+		if (StringUtils.hasText(body) && this.mapper != null) {
 			if (body.startsWith("[")) {
-				Class<?> collectionType = Collection.class.isAssignableFrom(inputType) ? inputType : Collection.class;
-				input = mapper.toObject(body, ResolvableType
-						.forClassWithGenerics(collectionType, (Class<?>) itemType)
-						.getType());
+				Class<?> collectionType = Collection.class.isAssignableFrom(inputType)
+						? inputType
+						: Collection.class;
+				input = mapper.toObject(body,
+						ResolvableType
+								.forClassWithGenerics(collectionType, (Class<?>) itemType)
+								.getType());
 			}
 			else {
 				if (inputType == String.class) {
@@ -124,7 +155,7 @@ public class RequestProcessor {
 				}
 			}
 		}
-		return post(wrapper, input, null, stream);
+		return response(wrapper, input, stream);
 	}
 
 	public Mono<ResponseEntity<?>> stream(FunctionWrapper request) {
@@ -134,19 +165,17 @@ public class RequestProcessor {
 		return stream(request, result);
 	}
 
-	private Mono<ResponseEntity<?>> post(FunctionWrapper wrapper, Object body,
-			MultiValueMap<String, String> params, boolean stream) {
+	private Mono<ResponseEntity<?>> response(FunctionWrapper wrapper, Object body,
+			boolean stream) {
 
 		Iterable<?> iterable = body instanceof Collection ? (Collection<?>) body
-				: (body instanceof Set ? Collections.singleton(body) : Collections.singletonList(body));
+				: (body instanceof Set ? Collections.singleton(body)
+						: Collections.singletonList(body));
 
 		Function<Publisher<?>, Publisher<?>> function = wrapper.function();
 		Consumer<Publisher<?>> consumer = wrapper.consumer();
 
 		MultiValueMap<String, String> form = wrapper.params();
-		if (params != null) {
-			form.putAll(params);
-		}
 
 		boolean inputIsCollection = Collection.class
 				.isAssignableFrom(inspector.getInputType(wrapper.handler()));
@@ -250,6 +279,98 @@ public class RequestProcessor {
 		}
 	}
 
+	private Publisher<?> body(Object handler, ServerWebExchange exchange) {
+
+		ResolvableType elementType = ResolvableType
+				.forClass(this.inspector.getInputType(handler));
+		ResolvableType actualType = elementType;
+		Class<?> resolvedType = elementType.resolve();
+		ReactiveAdapter adapter = (resolvedType != null
+				? getAdapterRegistry().getAdapter(resolvedType)
+				: null);
+
+		ServerHttpRequest request = exchange.getRequest();
+		ServerHttpResponse response = exchange.getResponse();
+
+		MediaType contentType = request.getHeaders().getContentType();
+		MediaType mediaType = (contentType != null ? contentType
+				: MediaType.APPLICATION_OCTET_STREAM);
+
+		if (logger.isDebugEnabled()) {
+			logger.debug(exchange.getLogPrefix() + (contentType != null
+					? "Content-Type:" + contentType
+					: "No Content-Type, using " + MediaType.APPLICATION_OCTET_STREAM));
+		}
+		boolean isBodyRequired = (adapter != null && !adapter.supportsEmpty());
+
+		MethodParameter bodyParam = new MethodParameter(handlerMethod(handler), 0);
+		for (HttpMessageReader<?> reader : getMessageReaders()) {
+			if (reader.canRead(elementType, mediaType)) {
+				Map<String, Object> readHints = Hints.from(Hints.LOG_PREFIX_HINT,
+						exchange.getLogPrefix());
+				if (adapter != null && adapter.isMultiValue()) {
+					if (logger.isDebugEnabled()) {
+						logger.debug(
+								exchange.getLogPrefix() + "0..N [" + elementType + "]");
+					}
+					Flux<?> flux = reader.read(actualType, elementType, request, response,
+							readHints);
+					flux = flux.onErrorResume(
+							ex -> Flux.error(handleReadError(bodyParam, ex)));
+					if (isBodyRequired) {
+						flux = flux.switchIfEmpty(
+								Flux.error(() -> handleMissingBody(bodyParam)));
+					}
+					return Mono.just(adapter.fromPublisher(flux));
+				}
+				else {
+					// Single-value (with or without reactive type wrapper)
+					if (logger.isDebugEnabled()) {
+						logger.debug(
+								exchange.getLogPrefix() + "0..1 [" + elementType + "]");
+					}
+					Mono<?> mono = reader.readMono(actualType, elementType, request,
+							response, readHints);
+					mono = mono.onErrorResume(
+							ex -> Mono.error(handleReadError(bodyParam, ex)));
+					if (isBodyRequired) {
+						mono = mono.switchIfEmpty(
+								Mono.error(() -> handleMissingBody(bodyParam)));
+					}
+					return (adapter != null ? Mono.just(adapter.fromPublisher(mono))
+							: Mono.from(mono));
+				}
+			}
+		}
+
+		return Mono.error(new UnsupportedMediaTypeStatusException(mediaType,
+				Arrays.asList(MediaType.APPLICATION_JSON), elementType));
+	}
+
+	private Method handlerMethod(Object handler) {
+		return ReflectionUtils.findMethod(handler.getClass(), "apply", (Class<?>[]) null);
+	}
+
+	public List<HttpMessageReader<?>> getMessageReaders() {
+		return this.messageReaders;
+	}
+
+	private Throwable handleReadError(MethodParameter parameter, Throwable ex) {
+		return (ex instanceof DecodingException
+				? new ServerWebInputException("Failed to read HTTP message", parameter,
+						ex)
+				: ex);
+	}
+
+	private ServerWebInputException handleMissingBody(MethodParameter param) {
+		return new ServerWebInputException(
+				"Request body is missing: " + param.getExecutable().toGenericString());
+	}
+
+	private ReactiveAdapterRegistry getAdapterRegistry() {
+		return ReactiveAdapterRegistry.getSharedInstance();
+	}
+
 	private Publisher<?> value(Function<Publisher<?>, Publisher<?>> function,
 			Publisher<String> value) {
 		Flux<?> input = Flux.from(value).map(body -> converter.convert(function, body));

spring-cloud-function-web/src/main/java/org/springframework/cloud/function/web/flux/FunctionController.java

@@ -83,6 +83,13 @@ public class FunctionController {
 		return map;
 	}
 
+	@PostMapping(path = "/**", consumes = MediaType.APPLICATION_OCTET_STREAM_VALUE)
+	@ResponseBody
+	public Mono<ResponseEntity<?>> post(ServerWebExchange request) {
+		FunctionWrapper wrapper = wrapper(request);
+		return processor.post(wrapper, request);
+	}
+
 	@PostMapping(path = "/**")
 	@ResponseBody
 	public Mono<ResponseEntity<?>> post(ServerWebExchange request,

spring-cloud-function-web/src/main/java/org/springframework/cloud/function/web/function/FunctionEndpointInitializer.java

@@ -106,7 +106,8 @@ class FunctionEndpointInitializer
 		context.registerBean(RequestProcessor.class,
 				() -> new RequestProcessor(context.getBean(FunctionInspector.class),
 						context.getBeanProvider(JsonMapper.class),
-						context.getBean(StringConverter.class)));
+						context.getBean(StringConverter.class),
+						context.getBeanProvider(ServerCodecConfigurer.class)));
 		context.registerBean(FunctionEndpointFactory.class,
 				() -> new FunctionEndpointFactory(context.getBean(FunctionCatalog.class),
 						context.getBean(FunctionInspector.class),
@@ -226,7 +227,8 @@ class FunctionEndpointFactory {
 			logger.info("Found functions: " + names);
 			if (handler != null) {
 				logger.info("Configured function: " + handler);
-				Assert.isTrue(names.contains(handler), "Cannot locate function: " + handler);
+				Assert.isTrue(names.contains(handler),
+						"Cannot locate function: " + handler);
 				return catalog.lookup(Function.class, handler);
 			}
 			return catalog.lookup(Function.class, names.iterator().next());