GH-718 Improve support for Function bean definition

Added sample for functional bean definition

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

@@ -52,8 +52,6 @@ public class CustomRuntimeInitializer implements ApplicationContextInitializer<G
 			if (context.getBeanFactory().getBeanNamesForType(DestinationResolver.class, false, false).length == 0) {
 				context.registerBean(LambdaDestinationResolver.class, () -> new LambdaDestinationResolver());
 			}
-			context.registerBean(StringUtils.uncapitalize(CustomRuntimeAutoConfiguration.class.getSimpleName()),
-					CommandLineRunner.class, () -> args -> CustomRuntimeAutoConfiguration.background());
 		}
 	}
 

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

@@ -23,6 +23,7 @@ import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Set;
 
 import com.amazonaws.services.lambda.runtime.Context;
 import com.amazonaws.services.lambda.runtime.RequestStreamHandler;
@@ -34,9 +35,11 @@ import reactor.core.publisher.Flux;
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.cloud.function.context.FunctionCatalog;
+import org.springframework.cloud.function.context.FunctionalSpringApplication;
 import org.springframework.cloud.function.context.catalog.SimpleFunctionRegistry.FunctionInvocationWrapper;
 import org.springframework.cloud.function.context.config.RoutingFunction;
 import org.springframework.cloud.function.utils.FunctionClassUtils;
+import org.springframework.context.ApplicationContextInitializer;
 import org.springframework.context.ConfigurableApplicationContext;
 import org.springframework.core.env.Environment;
 import org.springframework.messaging.Message;
@@ -117,7 +120,12 @@ public class FunctionInvoker implements RequestStreamHandler {
 	}
 
 	private void start() {
-		ConfigurableApplicationContext context = SpringApplication.run(FunctionClassUtils.getStartClass(), "--spring.main.web-application-type=none");
+		Class<?> startClass = FunctionClassUtils.getStartClass();
+		String[] properties = new String[] {"--spring.cloud.function.web.export.enabled=false", "--spring.main.web-application-type=none"};
+		ConfigurableApplicationContext context = ApplicationContextInitializer.class.isAssignableFrom(startClass)
+				? FunctionalSpringApplication.run(startClass, properties)
+						: SpringApplication.run(FunctionClassUtils.getStartClass(), properties);
+
 		Environment environment = context.getEnvironment();
 		String functionName = environment.getProperty("spring.cloud.function.definition");
 		FunctionCatalog functionCatalog = context.getBean(FunctionCatalog.class);
@@ -129,11 +137,21 @@ public class FunctionInvoker implements RequestStreamHandler {
 
 		this.function = functionCatalog.lookup(functionName, "application/json");
 
-		if (this.function == null && !CollectionUtils.isEmpty(functionCatalog.getNames(null))) {
+		Set<String> names = functionCatalog.getNames(null);
+		if (this.function == null && !CollectionUtils.isEmpty(names)) {
+
 			if (logger.isInfoEnabled()) {
-				logger.info("More then one function is available in FunctionCatalog. Will default to RoutingFunction, "
+				if (names.size() == 1) {
-						+ "expecting 'spring.cloud.function.definition' or 'spring.cloud.function.routing-expression' as Message headers. "
+					logger.info("Will default to RoutingFunction, since it is the only function available in FunctionCatalog."
-						+ "If invocation is over API Gateway, Message headers can be provided as HTTP headers.");
+							+ "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.");
+				}
+				else {
+					logger.info("More then one function is available in FunctionCatalog. " + names
+							+ " Will default to RoutingFunction, "
+							+ "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.");
+				}
 			}
 			this.function = functionCatalog.lookup(RoutingFunction.FUNCTION_NAME, "application/json");
 		}

spring-cloud-function-samples/function-functional-sample-aws/build.gradle

@@ -0,0 +1,93 @@
+buildscript {
+	ext {
+		springBootVersion = '2.2.0.BUILD-SNAPSHOT'
+		wrapperVersion = '1.0.17.RELEASE'
+		shadowVersion = '5.1.0'
+	}
+	repositories {
+		mavenLocal()
+		jcenter()
+		mavenCentral()
+		maven { url "https://repo.spring.io/snapshot" }
+		maven { url "https://repo.spring.io/milestone" }
+	}
+	dependencies {
+		classpath "com.github.jengelman.gradle.plugins:shadow:${shadowVersion}"
+		classpath("org.springframework.boot.experimental:spring-boot-thin-gradle-plugin:${wrapperVersion}")
+		classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
+		classpath("io.spring.gradle:dependency-management-plugin:1.0.8.RELEASE")
+	}
+}
+
+apply plugin: 'java'
+apply plugin: 'maven'
+apply plugin: 'eclipse'
+apply plugin: 'com.github.johnrengelman.shadow'
+apply plugin: 'org.springframework.boot'
+apply plugin: 'org.springframework.boot.experimental.thin-launcher'
+apply plugin: 'io.spring.dependency-management'
+
+group = 'io.spring.sample'
+version = '2.0.0.RELEASE'
+sourceCompatibility = 1.8
+targetCompatibility = 1.8
+
+repositories {
+	mavenLocal()
+	mavenCentral()
+	maven { url "https://repo.spring.io/snapshot" }
+	maven { url "https://repo.spring.io/milestone" }
+}
+
+ext {
+	springCloudFunctionVersion = "3.0.0.BUILD-SNAPSHOT"
+	awsLambdaEventsVersion = "2.0.2"
+	awsLambdaCoreVersion = "1.1.0"
+}
+ext['reactor.version'] = "3.1.7.RELEASE"
+
+assemble.dependsOn = [shadowJar, thinJar]
+
+jar {
+	manifest {
+		attributes 'Main-Class': 'example.Config'
+	}
+}
+
+import com.github.jengelman.gradle.plugins.shadow.transformers.*
+
+shadowJar {
+	classifier = 'aws'
+	dependencies {
+		exclude(
+			dependency("org.springframework.cloud:spring-cloud-function-web:${springCloudFunctionVersion}"))
+	}
+	// Required for Spring
+	mergeServiceFiles()
+	append 'META-INF/spring.handlers'
+	append 'META-INF/spring.schemas'
+	append 'META-INF/spring.tooling'
+	transform(PropertiesFileTransformer) {
+		paths = ['META-INF/spring.factories']
+		mergeStrategy = "append"
+	}
+}
+
+configurations {
+	testCompile.extendsFrom(compileOnly)
+}
+
+dependencyManagement {
+	imports {
+		mavenBom "org.springframework.cloud:spring-cloud-function-dependencies:${springCloudFunctionVersion}"
+	}
+}
+
+dependencies {
+	compile("org.springframework.cloud:spring-cloud-function-adapter-aws")
+	compile("org.springframework.cloud:spring-cloud-starter-function-webflux")
+	compile("org.springframework.boot:spring-boot-configuration-processor")
+	compileOnly("com.amazonaws:aws-lambda-java-events:${awsLambdaEventsVersion}")
+	compileOnly("com.amazonaws:aws-lambda-java-core:${awsLambdaCoreVersion}")
+	testCompile('org.springframework.boot:spring-boot-starter-test')
+}

spring-cloud-function-samples/function-functional-sample-aws/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.5.1-bin.zip

spring-cloud-function-samples/function-functional-sample-aws/gradlew

@@ -0,0 +1,164 @@
+#!/usr/bin/env bash
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+        PRG="$link"
+    else
+        PRG=`dirname "$PRG"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS=""
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn ( ) {
+    echo "$*"
+}
+
+die ( ) {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+        JAVACMD="$JAVA_HOME/bin/java"
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=$((i+1))
+    done
+    case $i in
+        (0) set -- ;;
+        (1) set -- "$args0" ;;
+        (2) set -- "$args0" "$args1" ;;
+        (3) set -- "$args0" "$args1" "$args2" ;;
+        (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Split up the JVM_OPTS And GRADLE_OPTS values into an array, following the shell quoting and substitution rules
+function splitJvmOpts() {
+    JVM_OPTS=("$@")
+}
+eval splitJvmOpts $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS
+JVM_OPTS[${#JVM_OPTS[*]}]="-Dorg.gradle.appname=$APP_BASE_NAME"
+
+exec "$JAVACMD" "${JVM_OPTS[@]}" -classpath "$CLASSPATH" org.gradle.wrapper.GradleWrapperMain "$@"

spring-cloud-function-samples/function-functional-sample-aws/gradlew.bat

@@ -0,0 +1,90 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS=
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+if "%@eval[2+2]" == "4" goto 4NT_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+goto execute
+
+:4NT_args
+@rem Get arguments from the 4NT Shell from JP Software
+set CMD_LINE_ARGS=%$
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

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

@@ -0,0 +1,150 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+		 xmlns="http://maven.apache.org/POM/4.0.0"
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+
+	<groupId>io.spring.sample</groupId>
+	<artifactId>function-functional-sample-aws</artifactId>
+	<version>2.0.0.RELEASE</version>
+	<packaging>jar</packaging>
+
+	<name>function-functional-sample-aws</name>
+	<description>Spring Cloud Function Sample for AWS Lambda functional style</description>
+
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.4.7</version>
+		<relativePath/> <!-- lookup parent from repository -->
+	</parent>
+
+	<properties>
+		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
+		<java.version>1.8</java.version>
+		<wrapper.version>1.0.17.RELEASE</wrapper.version>
+		<aws-lambda-events.version>3.9.0</aws-lambda-events.version>
+		<spring-cloud-function.version>3.2.0-SNAPSHOT</spring-cloud-function.version>
+	</properties>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-function-adapter-aws</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-function-web</artifactId>
+		</dependency>
+<!-- 		<dependency> -->
+<!-- 			<groupId>org.springframework.boot</groupId> -->
+<!-- 			<artifactId>spring-boot-starter-web</artifactId> -->
+<!-- 		</dependency> -->
+
+		<dependency>
+			<groupId>com.amazonaws</groupId>
+			<artifactId>aws-lambda-java-events</artifactId>
+			<version>${aws-lambda-events.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>com.amazonaws</groupId>
+			<artifactId>aws-lambda-java-core</artifactId>
+			<version>1.1.0</version>
+			<scope>provided</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-configuration-processor</artifactId>
+			<optional>true</optional>
+		</dependency>
+	</dependencies>
+
+	<dependencyManagement>
+		<dependencies>
+			<dependency>
+				<groupId>org.springframework.cloud</groupId>
+				<artifactId>spring-cloud-function-dependencies</artifactId>
+				<version>${spring-cloud-function.version}</version>
+				<type>pom</type>
+				<scope>import</scope>
+			</dependency>
+		</dependencies>
+	</dependencyManagement>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-deploy-plugin</artifactId>
+				<configuration>
+					<skip>true</skip>
+				</configuration>
+			</plugin>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+				<dependencies>
+					<dependency>
+						<groupId>org.springframework.boot.experimental</groupId>
+						<artifactId>spring-boot-thin-layout</artifactId>
+						<version>${wrapper.version}</version>
+					</dependency>
+				</dependencies>
+			</plugin>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-shade-plugin</artifactId>
+				<version>3.2.4</version>
+				<configuration>
+					<createDependencyReducedPom>false</createDependencyReducedPom>
+					<shadedArtifactAttached>true</shadedArtifactAttached>
+					<shadedClassifierName>aws</shadedClassifierName>
+				</configuration>
+			</plugin>
+		</plugins>
+	</build>
+
+	<repositories>
+		<repository>
+			<id>spring-snapshots</id>
+			<name>Spring Snapshots</name>
+			<url>https://repo.spring.io/snapshot</url>
+			<snapshots>
+				<enabled>true</enabled>
+			</snapshots>
+		</repository>
+		<repository>
+			<id>spring-milestones</id>
+			<name>Spring Milestones</name>
+			<url>https://repo.spring.io/milestone</url>
+			<snapshots>
+				<enabled>false</enabled>
+			</snapshots>
+		</repository>
+	</repositories>
+	<pluginRepositories>
+		<pluginRepository>
+			<id>spring-snapshots</id>
+			<name>Spring Snapshots</name>
+			<url>https://repo.spring.io/snapshot</url>
+			<snapshots>
+				<enabled>true</enabled>
+			</snapshots>
+		</pluginRepository>
+		<pluginRepository>
+			<id>spring-milestones</id>
+			<name>Spring Milestones</name>
+			<url>https://repo.spring.io/milestone</url>
+			<snapshots>
+				<enabled>false</enabled>
+			</snapshots>
+		</pluginRepository>
+	</pluginRepositories>
+
+</project>

spring-cloud-function-samples/function-functional-sample-aws/src/main/java/example/FunctionConfiguration.java

@@ -0,0 +1,30 @@
+package example;
+
+import java.util.function.Function;
+
+import org.springframework.boot.SpringBootConfiguration;
+import org.springframework.cloud.function.context.FunctionRegistration;
+import org.springframework.cloud.function.context.FunctionType;
+import org.springframework.context.ApplicationContextInitializer;
+import org.springframework.context.support.GenericApplicationContext;
+
+@SpringBootConfiguration
+public class FunctionConfiguration implements ApplicationContextInitializer<GenericApplicationContext> {
+
+	/*
+	 * You need this main method (empty) or explicit <start-class>example.FunctionConfiguration</start-class>
+	 * in the POM to ensure boot plug-in makes the correct entry
+	 */
+    public static void main(String[] args) {
+    	// empty unless using Custom runtime at which point it should include
+    	// FunctionalSpringApplication.run(FunctionConfiguration.class, args);
+    }
+
+    @Override
+    public void initialize(GenericApplicationContext context) {
+    	Function<String, String> function = (str) -> str + str.toUpperCase();
+    	context.registerBean("uppercase", FunctionRegistration.class,
+				() -> new FunctionRegistration<>(function).type(
+						FunctionType.from(String.class).to(String.class)));
+    }
+}

spring-cloud-function-samples/function-functional-sample-aws/src/main/resources/application.properties

@@ -0,0 +1,4 @@
+logging.level.org.springframework.cloud=DEBUG
+#spring.cloud.function.web.export.enabled=false
+#spring.main.web-application-type=none
+#spring.functional.enabled=true

spring-cloud-function-samples/function-functional-sample-aws/src/main/resources/log4j.properties

@@ -0,0 +1,20 @@
+log4j.rootCategory=DEBUG, LAMBDA
+PID=????
+LOG_LEVEL_PATTERN=%5p
+LOG_PATTERN=[%d{yyyy-MM-dd HH:mm:ss.SSS}] boot%X{context} - ${PID} ${LOG_LEVEL_PATTERN} [%t] --- %c{1}: %m%n
+# CONSOLE is set to be a ConsoleAppender using a PatternLayout.
+log4j.appender.LAMBDA=com.amazonaws.services.lambda.runtime.log4j.LambdaAppender
+log4j.appender.LAMBDA.layout=org.apache.log4j.PatternLayout
+log4j.appender.LAMBDA.layout.conversionPattern=${LOG_PATTERN}
+log4j.category.org.apache.catalina.startup.DigesterFactory=ERROR
+log4j.category.org.apache.catalina.util.LifecycleBase=ERROR
+log4j.category.org.apache.coyote.http11.Http11NioProtocol=WARN
+log4j.category.org.apache.sshd.common.util.SecurityUtils
+log4j.category.org.apache.tomcat.util.net.NioSelectorPool=WARN
+log4j.category.org.crsh.plugin=WARN
+log4j.category.org.crsh.ssh=WARN
+log4j.category.org.eclipse.jetty.util.component.AbstractLifeCycle=ERROR
+log4j.category.org.hibernate.validator.internal.util.Version=WARN
+log4j.category.org.springframework.boot.actuate.autoconfigure.CrshAutoConfiguration=WARN
+log4j.category.org.springframework.boot.actuate.endpoint.jmx=WARN
+log4j.category.org.thymeleaf=WARN

spring-cloud-function-samples/function-functional-sample-aws/src/test/java/example/MapTests.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2012-2019 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 example;
+
+import org.junit.jupiter.api.Test;
+
+/**
+ * @author Dave Syer
+ *
+ */
+public class MapTests {
+
+	@Test
+	public void test() {
+
+	}
+}

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

@@ -37,10 +37,10 @@
 			<groupId>org.springframework.cloud</groupId>
 			<artifactId>spring-cloud-function-web</artifactId>
 		</dependency>
-		<dependency>
+<!-- 		<dependency> -->
-			<groupId>org.springframework.boot</groupId>
+<!-- 			<groupId>org.springframework.boot</groupId> -->
-			<artifactId>spring-boot-starter-web</artifactId>
+<!-- 			<artifactId>spring-boot-starter-web</artifactId> -->
-		</dependency>
+<!-- 		</dependency> -->
 
 		<dependency>
 			<groupId>com.amazonaws</groupId>

spring-cloud-function-samples/function-sample-aws/src/main/java/example/FunctionConfiguration.java

@@ -2,7 +2,6 @@ package example;
 
 import java.util.function.Function;
 
-import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.context.annotation.Bean;
 
@@ -10,11 +9,12 @@ import org.springframework.context.annotation.Bean;
 public class FunctionConfiguration {
 
 	/*
-	 * You need this main method or explicit <start-class>example.FunctionConfiguration</start-class>
+	 * You need this main method (empty) or explicit <start-class>example.FunctionConfiguration</start-class>
 	 * in the POM to ensure boot plug-in makes the correct entry
 	 */
 	public static void main(String[] args) {
-		SpringApplication.run(FunctionConfiguration.class, args);
+		// empty unless using Custom runtime at which point it should include
+		// SpringApplication.run(FunctionConfiguration.class, args);
 	}
 
 	@Bean

spring-cloud-function-samples/pom.xml

@@ -18,6 +18,7 @@
 		<module>function-sample-pof</module>
 		<module>function-sample-pojo</module>
 		<module>function-sample-aws</module>
+		<module>function-functional-sample-aws</module>
 		<module>function-sample-aws-routing</module>
 		<module>function-sample-aws-custom</module>
 		<module>function-sample-aws-custom-bean</module>