Add a sample app with just beans that are Functions

Make it deployable via its maven coordinates in
spring-cloud-function-deployer (it is deployed by default on start
up right now, but that's just a demo)

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

@@ -0,0 +1,57 @@
+/*
+ * Copyright 2016-2017 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.deployer;
+
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import org.springframework.boot.test.web.client.TestRestTemplate;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.util.SocketUtils;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * @author Dave Syer
+ *
+ */
+public class FunctionExtractingAppDeployerIntegrationTests {
+
+	private static ConfigurableApplicationContext context;
+	private static int port;
+
+	@BeforeClass
+	public static void open() {
+		port = SocketUtils.findAvailableTcpPort();
+		context = new ApplicationRunner().start("--server.port=" + port);
+	}
+
+	@AfterClass
+	public static void close() {
+		if (context != null) {
+			context.close();
+		}
+	}
+
+	@Test
+	public void test() {
+		assertThat(new TestRestTemplate()
+				.getForObject("http://localhost:" + port + "/words", String.class))
+						.isEqualTo("foobar");
+	}
+
+}

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

@@ -0,0 +1,96 @@
+/*
+ * Copyright 2016-2017 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.deployer;
+
+import java.util.Arrays;
+import java.util.Collections;
+
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+
+import org.springframework.boot.loader.thin.ArchiveUtils;
+import org.springframework.boot.loader.tools.LogbackInitializer;
+import org.springframework.cloud.deployer.spi.app.DeploymentState;
+import org.springframework.cloud.deployer.spi.core.AppDefinition;
+import org.springframework.cloud.deployer.spi.core.AppDeploymentRequest;
+import org.springframework.core.io.FileSystemResource;
+import org.springframework.core.io.Resource;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import reactor.core.publisher.Flux;
+
+/**
+ * @author Dave Syer
+ *
+ */
+public class FunctionExtractingAppDeployerTests {
+
+	private static String id;
+
+	static {
+		LogbackInitializer.initialize();
+	}
+
+	private static FunctionExtractingAppDeployer deployer = new FunctionExtractingAppDeployer();
+
+	@Rule
+	public ExpectedException expected = ExpectedException.none();
+
+	@Before
+	public void init() throws Exception {
+		if (id == null) {
+			id = deploy("maven://com.example:function-sample:1.0.0.BUILD-SNAPSHOT");
+			// "--debug");
+		}
+		assertThat(deployer.status(id).getState()).isEqualTo(DeploymentState.deployed);
+	}
+
+	@Test
+	public void deployAndExtractFunctions() throws Exception {
+		// This one can only work if you change the boot classpath to contain reactor-core
+		// and reactive-streams
+		expected.expect(ClassCastException.class);
+		@SuppressWarnings("unchecked")
+		Flux<String> result = (Flux<String>) deployer.lookupFunction("uppercase")
+				.apply(Flux.just("foo"));
+		assertThat(result.blockFirst()).isEqualTo("FOO");
+	}
+
+	@Test
+	public void deployAndExtractConsumers() throws Exception {
+		assertThat(deployer.lookupConsumer("sink")).isNull();
+	}
+
+	@Test
+	public void deployAndExtractSuppliers() throws Exception {
+		assertThat(deployer.lookupSupplier("words")).isNotNull();
+	}
+
+	private String deploy(String jarName, String... args) throws Exception {
+		Resource resource = new FileSystemResource(
+				ArchiveUtils.getArchiveRoot(ArchiveUtils.getArchive(jarName)));
+		AppDefinition definition = new AppDefinition(resource.getFilename(),
+				Collections.emptyMap());
+		AppDeploymentRequest request = new AppDeploymentRequest(definition, resource,
+				Collections.emptyMap(), Arrays.asList(args));
+		String deployed = deployer.deploy(request);
+		return deployed;
+	}
+
+}