Add Supplier Exporter sample

spring-cloud-function-samples/function-sample-supplier-exporter/src/test/java/com/example/demo/DemoApplicationTests.java

@@ -0,0 +1,55 @@
+package com.example.demo;
+
+import com.example.test.TestServer;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.boot.SpringApplication;
+import org.springframework.cloud.function.context.test.FunctionalSpringBootTest;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.util.SocketUtils;
+import org.springframework.web.reactive.function.client.WebClient;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@FunctionalSpringBootTest({"spring.cloud.function.web.export.source.url=http://localhost:${export.port}/home",
+    "spring.cloud.function.web.export.sink.url=http://localhost:${export.port}/echo",
+    "logging.level.reactor=OFF",
+    "logging.level.io.netty=OFF"})
+public class DemoApplicationTests {
+
+    static ConfigurableApplicationContext context;
+
+    @Value("${export.port}")
+    private int port;
+
+    @Autowired
+    private WebClient.Builder builder;
+
+	@Test
+	public void contextLoads() throws Exception {
+        WebClient client = builder.baseUrl("http://localhost:" + port).build();
+        client.post().uri("/add").bodyValue("{\"name\":\"Fred\"}").exchange().block();
+        Thread.sleep(1000L);
+        String response = client.get().uri("/take").exchange().block().bodyToMono(String.class).block();
+        assertThat(response).isEqualTo("{\"name\":\"hi Fred!\"}");
+    }
+
+    @AfterAll
+    static void after() {
+        if (context != null) {
+            context.close();
+        }
+    }
+
+    @BeforeAll
+    static void before() {
+        int port = SocketUtils.findAvailableTcpPort();
+        System.setProperty("export.port", "" + port);
+        context = SpringApplication.run(TestServer.class, "--server.port="+port, "--spring.cloud.function.web.export.enabled=false", "--spring.main.web-application-type=reactive");
+    }
+
+}