Experimental Azure function adapter for HTTP trigger

spring-cloud-function-adapters/pom.xml

@@ -17,6 +17,7 @@
 	<modules>
 		<module>spring-cloud-function-adapter-aws</module>
 		<module>spring-cloud-function-adapter-openwhisk</module>
+		<module>spring-cloud-function-adapter-azure</module>
   	</modules>
 
 </project>

spring-cloud-function-adapters/spring-cloud-function-adapter-azure/README.adoc

@@ -0,0 +1,75 @@
+This work is experimental.
+This project provides an adapter layer for a Spring Cloud Function application onto Azure.
+You can write an app with a single `@Bean` of type `Function` and it will be deployable in Azure if you get the JAR file laid out right.
+
+The adapter has a generic http request handler that you can use.
+There is a `AzureSpringBootRequestHandler` which you must extend, and provide the input and output types as type parameters (enabling Azure to inspect the class and do the JSON conversions itself).
+
+If your app has more than one `@Bean` of type `Function` etc. then you can choose the one to use by configuring `function.name`.
+The functions are extracted from the Spring Cloud `FunctionCatalog`.
+
+=== Notes on JAR Layout
+
+You don't need the Spring Cloud Function Web at runtime in Azure, so you need to exclude this before you create the JAR you deploy to Azure.
+A function application on Azure has to be shaded, but a Spring Boot standalone application does not, so you can run the same app using 2 separate jars (as per the sample here).
+The sample app creates the shaded jar file, with an `azure` classifier for deploying in Azure.
+
+== Build
+
+----
+./mvnw -U clean package
+----
+
+== Running the sample
+
+Before running the sample, we need to install a custom azure maven plugin.
+Checkout this fork: https://github.com/sobychacko/azure-maven-plugins/tree/for-spring-boot-apps
+----
+cd azure-functions-maven-plugin
+mvn clean install -Dcheckstyle.skip=true -DskipTests -Dfindbugs.skip=true
+----
+
+Build the sample under `spring-cloud-function-samples/function-sample-azure`.
+
+----
+mvn clean package
+----
+
+Running Azure function locally.
+
+----
+mvn azure-functions:run
+
+On another terminal try this: curl localhost:7071/api/uppercase -d '{"value": "hello foobar"}'
+----
+
+Deploying the function that ran locally on Azure runtime.
+
+----
+az login
+
+mvn azure-functions:deploy
+
+On another terminal try this: curl https://<azure-function-url-from-the-log>/api/uppercase -d '{"value": "hello foobar!"}'
+
+Please ensure that you use the right URL for the function above.
+----
+
+Running the function as a standalone Spring Boot app
+
+Go to the samples project and uncomment `spring-cloud-function-web` dependency and `spring-boot-maven-plugin`.
+
+----
+mvn clean package
+java -jar target/<spring boot uber jar>
+
+On another terminal: curl -H "Content-Type: text/plain" localhost:8080/function -d '{"value": "hello foobar"}'
+----
+
+The input type for the function in the Azure sample is a Foo with a single property called "value". So you would need this to test it with something as below.
+
+----
+{
+  "value": "foobar"
+}
+----

spring-cloud-function-adapters/spring-cloud-function-adapter-azure/pom.xml

@@ -0,0 +1,89 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>spring-cloud-function-adapter-azure</artifactId>
+    <packaging>jar</packaging>
+
+    <name>spring-cloud-function-adapter-aws</name>
+    <description>Azure Function Adapter for Spring Cloud Function</description>
+
+    <parent>
+        <groupId>org.springframework.cloud</groupId>
+        <artifactId>spring-cloud-function-adapter-parent</artifactId>
+        <version>1.0.0.BUILD-SNAPSHOT</version>
+    </parent>
+
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
+        <java.version>1.8</java.version>
+        <aws-lambda-events.version>1.2.1</aws-lambda-events.version>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.cloud</groupId>
+            <artifactId>spring-cloud-function-context</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.projectreactor</groupId>
+            <artifactId>reactor-core</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>com.microsoft.azure</groupId>
+            <artifactId>azure-functions-java-core</artifactId>
+            <version>[1.0.0-beta-1,1.0.0)</version>
+        </dependency>
+
+    </dependencies>
+
+    <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-adapters/spring-cloud-function-adapter-azure/src/main/java/org/springframework/cloud/function/adapter/azure/AzureSpringBootRequestHandler.java

@@ -0,0 +1,67 @@
+/*
+ * 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.adapter.azure;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+
+import com.microsoft.azure.serverless.functions.ExecutionContext;
+import reactor.core.publisher.Flux;
+
+/**
+ * @author Soby Chacko
+ */
+public class AzureSpringBootRequestHandler<I,O> extends AzureSpringFunctionInitializer {
+
+	public Object handleRequest(I foo, ExecutionContext context) {
+		context.getLogger().info("Handler Java HTTP trigger processed a request.");
+		initialize(context);
+
+		Object convertedEvent = convertEvent(foo);
+		Flux<?> output = apply(extract(convertedEvent));
+		return result(convertedEvent, output);
+	}
+
+	protected Object convertEvent(I input) {
+		return input;
+	}
+
+	private Flux<?> extract(Object input) {
+		if (input instanceof Collection) {
+			return Flux.fromIterable((Iterable<?>) input);
+		}
+		return Flux.just(input);
+	}
+
+	private Object result(Object input, Flux<?> output) {
+		List<Object> result = new ArrayList<>();
+		for (Object value : output.toIterable()) {
+			result.add(value);
+		}
+		if (isSingleValue(input) && result.size()==1) {
+			return result.get(0);
+		}
+		return result;
+	}
+
+	private boolean isSingleValue(Object input) {
+		return !(input instanceof Collection);
+	}
+
+
+}

spring-cloud-function-adapters/spring-cloud-function-adapter-azure/src/main/java/org/springframework/cloud/function/adapter/azure/AzureSpringFunctionInitializer.java

@@ -0,0 +1,163 @@
+/*
+ * 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.adapter.azure;
+
+import java.io.Closeable;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URL;
+import java.util.Collections;
+import java.util.List;
+import java.util.Set;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.function.Function;
+import java.util.jar.Manifest;
+
+import com.microsoft.azure.serverless.functions.ExecutionContext;
+import reactor.core.publisher.Flux;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.builder.SpringApplicationBuilder;
+import org.springframework.cloud.function.core.FunctionCatalog;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.util.ClassUtils;
+
+/**
+ * @author Soby Chacko
+ */
+public class AzureSpringFunctionInitializer implements Closeable {
+
+	private Function<Flux<?>, Flux<?>> function;
+
+	private AtomicBoolean initialized = new AtomicBoolean();
+
+	private  Class<?> configurationClass;
+
+	@Autowired(required = false)
+	private FunctionCatalog catalog;
+
+	private static ConfigurableApplicationContext context;
+
+	public AzureSpringFunctionInitializer(Class<?> configurationClass) {
+		this.configurationClass = configurationClass;
+	}
+
+	public AzureSpringFunctionInitializer() {
+		this(getStartClass());
+	}
+
+
+	@Override
+	public void close() throws IOException {
+		if (AzureSpringFunctionInitializer.context != null) {
+			AzureSpringFunctionInitializer.context.close();
+		}
+	}
+
+	@SuppressWarnings("unchecked")
+	protected void initialize(ExecutionContext ctxt) {
+
+		ConfigurableApplicationContext context = AzureSpringFunctionInitializer.context;
+		
+		if (!this.initialized.compareAndSet(false, true)) {
+			return;
+		}
+		ctxt.getLogger().info("Initializing function");
+		
+		if (context==null) {
+			synchronized (AzureSpringFunctionInitializer.class) {
+				if (context==null) {
+					SpringApplicationBuilder builder = new SpringApplicationBuilder(
+							configurationClass);
+					ClassUtils.overrideThreadContextClassLoader(AzureSpringFunctionInitializer.class.getClassLoader());
+
+					context = builder.web(false).run();
+					AzureSpringFunctionInitializer.context = context;
+				}
+			}
+			
+		}
+
+		context.getAutowireCapableBeanFactory().autowireBean(this);
+		String name = context.getEnvironment().getProperty("function.name");
+
+		if (name == null) {
+			name = "function";
+		}
+		if (this.catalog == null) {
+			this.function = context.getBean(name, Function.class);
+		}
+		else {
+			Set<String> functionNames = this.catalog.getFunctionNames();
+			this.function = this.catalog.lookupFunction(functionNames.iterator().next());
+		}
+	}
+
+	protected Flux<?> apply(Flux<?> input) {
+		if (this.function != null) {
+			return function.apply(input);
+		}
+		throw new IllegalStateException("No function defined");
+	}
+
+	private static Class<?> getStartClass() {
+		ClassLoader classLoader = org.springframework.cloud.function.adapter.azure.AzureSpringFunctionInitializer.class.getClassLoader();
+		if (System.getenv("MAIN_CLASS") != null) {
+			return ClassUtils.resolveClassName(System.getenv("MAIN_CLASS"), classLoader);
+		}
+		try {
+			Class<?> result = getStartClass(
+					Collections.list(classLoader.getResources("META-INF/MANIFEST.MF")));
+			if (result == null) {
+				result = getStartClass(Collections
+						.list(classLoader.getResources("meta-inf/manifest.mf")));
+			}
+			return result;
+		}
+		catch (Exception ex) {
+			return null;
+		}
+	}
+
+	private static Class<?> getStartClass(List<URL> list) {
+		for (URL url : list) {
+			try {
+				InputStream inputStream = url.openStream();
+				try {
+					Manifest manifest = new Manifest(inputStream);
+					String startClass = manifest.getMainAttributes()
+							.getValue("Main-Class");
+					if (startClass != null) {
+						Class<?> aClass = ClassUtils.forName(startClass,
+								org.springframework.cloud.function.adapter.azure.AzureSpringFunctionInitializer.class.getClassLoader());
+						SpringBootApplication declaredAnnotation = aClass.getDeclaredAnnotation(SpringBootApplication.class);
+						if (declaredAnnotation != null) {
+							return aClass;
+						}
+					}
+				}
+				finally {
+					inputStream.close();
+				}
+			}
+			catch (Exception ex) {
+			}
+		}
+		return null;
+	}
+}

spring-cloud-function-samples/function-sample-azure/host.json

@@ -0,0 +1,2 @@
+{
+}

spring-cloud-function-samples/function-sample-azure/local.settings.json

@@ -0,0 +1,7 @@
+{
+  "IsEncrypted": false,
+  "Values": {
+    "AzureWebJobsStorage": "",
+    "AzureWebJobsDashboard": ""
+  }
+}

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

@@ -0,0 +1,155 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>io.spring.sample</groupId>
+    <artifactId>function-sample-azure</artifactId>
+    <version>1.0.0.BUILD-SNAPSHOT</version>
+    <packaging>jar</packaging>
+
+    <name>Azure Java Functions</name>
+
+    <parent>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-starter-parent</artifactId>
+        <version>1.5.8.RELEASE</version>
+        <relativePath /> <!-- lookup parent from repository -->
+    </parent>
+
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <maven.compiler.source>1.8</maven.compiler.source>
+        <maven.compiler.target>1.8</maven.compiler.target>
+        <functionAppName>function-sample-azure-11262017190909</functionAppName>
+        <functionAppRegion>westus</functionAppRegion>
+        <start-class>example.FooConfig</start-class>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>com.microsoft.azure</groupId>
+            <artifactId>azure-functions-java-core</artifactId>
+            <version>[1.0.0-beta-1,1.0.0)</version>
+        </dependency>
+        <!--<dependency>-->
+            <!--<groupId>org.springframework.cloud</groupId>-->
+            <!--<artifactId>spring-cloud-function-web</artifactId>-->
+            <!--<version>1.0.0.BUILD-SNAPSHOT</version>-->
+        <!--</dependency>-->
+        <dependency>
+            <groupId>org.springframework.cloud</groupId>
+            <artifactId>spring-cloud-function-adapter-azure</artifactId>
+            <version>1.0.0.BUILD-SNAPSHOT</version>
+        </dependency>
+        <dependency>
+            <groupId>io.projectreactor</groupId>
+            <artifactId>reactor-core</artifactId>
+            <version>3.0.7.RELEASE</version>
+        </dependency>
+
+        <!-- Test -->
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.12</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-core</artifactId>
+            <version>2.4.0</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <pluginManagement>
+            <plugins>
+                <plugin>
+                    <artifactId>maven-resources-plugin</artifactId>
+                    <version>3.0.2</version>
+                </plugin>
+                <plugin>
+                    <groupId>com.microsoft.azure</groupId>
+                    <artifactId>azure-functions-maven-plugin</artifactId>
+                    <version>0.1.7-SNAPSHOT</version>
+                </plugin>
+            </plugins>
+        </pluginManagement>
+
+        <plugins>
+            <plugin>
+                <groupId>com.microsoft.azure</groupId>
+                <artifactId>azure-functions-maven-plugin</artifactId>
+                <configuration>
+                    <resourceGroup>java-functions-group</resourceGroup>
+                    <appName>${functionAppName}</appName>
+                    <region>${functionAppRegion}</region>
+                    <appSettings>
+                        <property>
+                            <name>FUNCTIONS_EXTENSION_VERSION</name>
+                            <value>beta</value>
+                        </property>
+                    </appSettings>
+                </configuration>
+                <executions>
+                    <execution>
+                        <id>package-functions</id>
+                        <goals>
+                            <goal>package</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+            <plugin>
+                <artifactId>maven-resources-plugin</artifactId>
+                <executions>
+                    <execution>
+                        <id>copy-resources</id>
+                        <phase>package</phase>
+                        <goals>
+                            <goal>copy-resources</goal>
+                        </goals>
+                        <configuration>
+                            <overwrite>true</overwrite>
+                            <outputDirectory>${project.build.directory}/azure-functions/${functionAppName}
+                            </outputDirectory>
+                            <resources>
+                                <resource>
+                                    <directory>${project.basedir}</directory>
+                                    <includes>
+                                        <include>host.json</include>
+                                        <include>local.settings.json</include>
+                                    </includes>
+                                </resource>
+                            </resources>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
+            <!--<plugin>-->
+                <!--<groupId>org.springframework.boot</groupId>-->
+                <!--<artifactId>spring-boot-maven-plugin</artifactId>-->
+            <!--</plugin>-->
+
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-shade-plugin</artifactId>
+                <configuration>
+                    <createDependencyReducedPom>false</createDependencyReducedPom>
+                    <shadedArtifactAttached>true</shadedArtifactAttached>
+                    <shadedClassifierName>azure</shadedClassifierName>
+                    <outputDirectory>${project.build.directory}/azure-functions/${functionAppName}</outputDirectory>
+                </configuration>
+            </plugin>
+
+        </plugins>
+
+    </build>
+
+
+
+
+</project>

spring-cloud-function-samples/function-sample-azure/src/main/java/example/Config.java

@@ -0,0 +1,85 @@
+/*
+ * 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 example;
+
+import java.util.function.Function;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.Bean;
+
+@SpringBootApplication
+class FooConfig {
+
+	@Bean
+	public Function<Foo, Bar> uppercase() {
+		return value -> new Bar(value.getValue().toUpperCase());
+	}
+
+	public static void main(String[] args) throws Exception {
+		SpringApplication.run(FooConfig.class, args);
+	}
+}
+
+class Foo {
+
+	private String value;
+
+	Foo() {
+	}
+
+	public String lowercase() {
+		return value.toLowerCase();
+	}
+
+	public Foo(String value) {
+		this.value = value;
+	}
+
+	public String uppercase() {
+		return value.toUpperCase();
+	}
+
+	public String getValue() {
+		return value;
+	}
+
+	public void setValue(String value) {
+		this.value = value;
+	}
+}
+
+class Bar {
+
+	private String value;
+
+	Bar() {
+	}
+
+	public Bar(String value) {
+		this.value = value;
+	}
+
+	public String getValue() {
+		return value;
+	}
+
+	public void setValue(String value) {
+		this.value = value;
+	}
+
+}

spring-cloud-function-samples/function-sample-azure/src/main/java/example/FooHandler.java

@@ -0,0 +1,34 @@
+/*
+ * 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 example;
+
+import com.microsoft.azure.serverless.functions.ExecutionContext;
+
+import org.springframework.cloud.function.adapter.azure.AzureSpringBootRequestHandler;
+
+/**
+ * @author Soby Chacko
+ */
+public class FooHandler extends AzureSpringBootRequestHandler {
+
+	@SuppressWarnings("unchecked")
+	public Bar handleRequest(Foo foo, ExecutionContext context) {
+		context.getLogger().info("Invoking entry point method");
+		return (Bar)super.handleRequest(foo,context);
+	}
+
+}

spring-cloud-function-samples/pom.xml

@@ -19,6 +19,7 @@
 		<module>function-sample-compiler</module>
 		<module>function-sample-task</module>
 		<module>function-sample-aws</module>
+		<module>function-sample-azure</module>
 	</modules>
 
 	<build>