GH-792 Fix Supplier streaming in s-c-function-web

Resolves #792

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

@@ -1,7 +1,7 @@
 <?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">
+	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>
@@ -14,29 +14,20 @@
 	<parent>
 		<groupId>org.springframework.boot</groupId>
 		<artifactId>spring-boot-starter-parent</artifactId>
-<<<<<<< HEAD
-		<version>2.6.1</version>
-=======
 		<version>3.0.0-SNAPSHOT</version>
->>>>>>> 4.x
-		<relativePath/>
+		<relativePath />
 	</parent>
 
 	<properties>
-<<<<<<< HEAD
-		<java.version>1.8</java.version>
-		<spring-cloud-function.version>3.2.2-SNAPSHOT</spring-cloud-function.version>
-=======
 		<spring-cloud-function.version>4.0.0-SNAPSHOT</spring-cloud-function.version>
->>>>>>> 4.x
 		<wrapper.version>1.0.27.RELEASE</wrapper.version>
 	</properties>
 
 	<dependencies>
 		<dependency>
-    <groupId>org.springframework.boot</groupId>
-    <artifactId>spring-boot-starter-actuator</artifactId>
-</dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-actuator</artifactId>
+		</dependency>
 		<dependency>
 			<groupId>org.springframework.cloud</groupId>
 			<artifactId>spring-cloud-starter-function-webflux</artifactId>

spring-cloud-function-samples/function-sample/src/main/java/com/example/Client.java

@@ -0,0 +1,44 @@
+/*
+ * 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 com.example;
+
+import org.springframework.web.reactive.function.client.WebClient;
+
+/**
+ * Sample client to test infinite stream from function.
+ *
+ * @author Oleg Zhurakousky
+ *
+ */
+public class Client {
+
+	public static void main(String[] args) throws Exception {
+		WebClient client = WebClient.create();
+		WebClient.ResponseSpec responseSpec = client.post()
+			    .uri("http://localhost:8080/infinite")
+			    .header("accept", "text/event-stream")
+			    .retrieve();
+
+		responseSpec.bodyToFlux(String.class).subscribe(v -> {
+			System.out.println(v);
+		});
+
+		System.in.read();
+
+	}
+
+}

spring-cloud-function-samples/function-sample/src/main/java/com/example/SampleApplication.java

@@ -16,10 +16,12 @@
 
 package com.example;
 
+import java.time.Duration;
 import java.util.function.Function;
 import java.util.function.Supplier;
 
 import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
@@ -55,9 +57,11 @@ public Supplier<String> hello() {
 	}
 
 	@Bean
-	public Supplier<Flux<String>> words() {
-		return () -> Flux.fromArray(new String[] {"foo", "bar"});
+	public Supplier<Flux<String>> infinite() {
+	    return () -> Flux
+	            .interval(Duration.ofSeconds(1))
+	            .log()
+	            .map(counter -> String.format("Counter: %s", counter));
 	}
 
 }
-// @checkstyle:on

spring-cloud-function-samples/function-sample/src/test/java/com/example/FunctionTests.java

@@ -51,15 +51,6 @@ public void testHello() {
 		assertThat(output).isEqualTo("hello");
 	}
 
-	@Test
-	public void testWords() {
-		Flux<String> output = this.functions.words().get();
-		List<String> results = output.collectList().block();
-		assertThat(results.size()).isEqualTo(2);
-		assertThat(results.get(0)).isEqualTo("foo");
-		assertThat(results.get(1)).isEqualTo("bar");
-	}
-
 	@Test
 	public void testGreeter() {
 		assertThat(new Greeter().apply("World")).isEqualTo("Hello World");

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

@@ -16,6 +16,7 @@
 
 package org.springframework.cloud.function.web.flux;
 
+import org.reactivestreams.Publisher;
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 
@@ -74,27 +75,25 @@ public Mono<ResponseEntity<?>> post(ServerWebExchange request,
 		return (Mono<ResponseEntity<?>>) FunctionWebRequestProcessingHelper.processRequest(wrapper(request), body, false);
 	}
 
-	@SuppressWarnings("unchecked")
 	@PostMapping(path = "/**", produces = MediaType.TEXT_EVENT_STREAM_VALUE)
 	@ResponseBody
-	public Mono<ResponseEntity<?>> postStream(ServerWebExchange request, @RequestBody(required = false) Flux<String> body) {
-		return (Mono<ResponseEntity<?>>) FunctionWebRequestProcessingHelper.processRequest(wrapper(request), body, false);
+	public Publisher<?> postStream(ServerWebExchange request, @RequestBody(required = false) Flux<String> body) {
+		return FunctionWebRequestProcessingHelper.processRequest(wrapper(request), body, true);
 	}
 
-	@SuppressWarnings("unchecked")
-	@GetMapping(path = "/**")
+	@GetMapping(path = "/**", produces = MediaType.TEXT_EVENT_STREAM_VALUE)
 	@ResponseBody
-	public Mono<ResponseEntity<?>> get(ServerWebExchange request) {
+	public Publisher<?> getStream(ServerWebExchange request) {
 		FunctionWrapper wrapper = wrapper(request);
-		return (Mono<ResponseEntity<?>>) FunctionWebRequestProcessingHelper.processRequest(wrapper, wrapper.getArgument(), false);
+		return FunctionWebRequestProcessingHelper.processRequest(wrapper, wrapper.getArgument(), true);
 	}
 
 	@SuppressWarnings("unchecked")
-	@GetMapping(path = "/**", produces = MediaType.TEXT_EVENT_STREAM_VALUE)
+	@GetMapping(path = "/**")
 	@ResponseBody
-	public Mono<ResponseEntity<?>> getStream(ServerWebExchange request) {
+	public Mono<ResponseEntity<?>> get(ServerWebExchange request) {
 		FunctionWrapper wrapper = wrapper(request);
-		return (Mono<ResponseEntity<?>>) FunctionWebRequestProcessingHelper.processRequest(wrapper, wrapper.getArgument(), true);
+		return (Mono<ResponseEntity<?>>) FunctionWebRequestProcessingHelper.processRequest(wrapper, wrapper.getArgument(), false);
 	}
 
 	private FunctionWrapper wrapper(ServerWebExchange request) {

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

@@ -94,21 +94,18 @@ public Mono<ResponseEntity<Publisher<?>>> postStream(WebRequest request,
 				.headers(response.getHeaders()).body((Publisher<?>) response.getBody()));
 	}
 
-	@SuppressWarnings("unchecked")
 	@GetMapping(path = "/**", produces = MediaType.TEXT_EVENT_STREAM_VALUE)
 	@ResponseBody
-	public Mono<ResponseEntity<Publisher<?>>> getStream(WebRequest request) {
+	public Publisher<?> getStream(WebRequest request) {
 		FunctionWrapper wrapper = wrapper(request);
-		return ((Mono<ResponseEntity<?>>) FunctionWebRequestProcessingHelper
-				.processRequest(wrapper, wrapper.getArgument(), true)).map(response -> ResponseEntity.ok()
-				.headers(response.getHeaders()).body((Publisher<?>) response.getBody()));
+		return FunctionWebRequestProcessingHelper
+				.processRequest(wrapper, wrapper.getArgument(), true);
 	}
 
 	@PostMapping(path = "/**")
 	@ResponseBody
 	public Object post(WebRequest request, @RequestBody(required = false) String body) {
-		String argument = StringUtils.hasText(body) ? body : "";
-		return FunctionWebRequestProcessingHelper.processRequest(wrapper(request), argument, false);
+		return FunctionWebRequestProcessingHelper.processRequest(wrapper(request), body, false);
 	}
 
 	@GetMapping(path = "/**")

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

@@ -84,7 +84,7 @@ public static Object invokeFunction(FunctionInvocationWrapper function, Object i
 	}
 
 	@SuppressWarnings({ "rawtypes", "unchecked" })
-	public static Object processRequest(FunctionWrapper wrapper, Object argument, boolean eventStream) {
+	public static Publisher<?> processRequest(FunctionWrapper wrapper, Object argument, boolean eventStream) {
 		FunctionInvocationWrapper function = wrapper.getFunction();
 
 		if (function == null) {
@@ -99,7 +99,7 @@ public static Object processRequest(FunctionWrapper wrapper, Object argument, bo
 			function.setSkipOutputConversion(true);
 		}
 
-		Object input = argument == null ? Flux.empty() : (argument instanceof Publisher ? Flux.from((Publisher) argument) : inputMessage);
+		Object input = argument == null ? "" : (argument instanceof Publisher ? Flux.from((Publisher) argument) : inputMessage);
 
 		Object result = function.apply(input);
 		if (function.isConsumer()) {
@@ -115,7 +115,7 @@ public static Object processRequest(FunctionWrapper wrapper, Object argument, bo
 		if (result instanceof Publisher) {
 			pResult = (Publisher) result;
 			if (eventStream) {
-				return Flux.from(pResult).then(Mono.fromSupplier(() -> responseOkBuilder.body(result)));
+				return Flux.from(pResult);
 			}
 
 			if (pResult instanceof Flux) {

spring-cloud-function-web/src/test/java/org/springframework/cloud/function/web/flux/HttpPostIntegrationTests.java

@@ -333,6 +333,8 @@ public void uppercaseJsonArray() throws Exception {
 	@Test
 	@DirtiesContext
 	public void uppercaseSSE() throws Exception {
+		String s = this.rest.exchange(RequestEntity.post(new URI("/uppercase")).contentType(MediaType.APPLICATION_JSON)
+				.body("[\"foo\",\"bar\"]"), String.class).getBody();
 		assertThat(this.rest.exchange(RequestEntity.post(new URI("/uppercase")).contentType(MediaType.APPLICATION_JSON)
 				.body("[\"foo\",\"bar\"]"), String.class).getBody())
 						.isEqualTo(sse("(FOO)", "(BAR)"));

spring-cloud-function-web/src/test/java/org/springframework/cloud/function/web/function/UserSubmittedTests.java

@@ -64,6 +64,18 @@ public void testIssue274() throws Exception {
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}
 
+	@Test
+	public void testIssue274WithData() throws Exception {
+		SpringApplication.run(Issue274Configuration.class);
+		TestRestTemplate testRestTemplate = new TestRestTemplate();
+		String port = System.getProperty("server.port");
+		Thread.sleep(200);
+		ResponseEntity<String> response = testRestTemplate
+				.postForEntity(new URI("http://localhost:" + port + "/echo"), "hello", String.class);
+		assertThat(response.getBody()).isEqualTo("HELLO");
+		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
+	}
+
 
 	@SpringBootApplication
 	protected static class Issue274Configuration {

spring-cloud-function-web/src/test/java/org/springframework/cloud/function/web/mvc/HttpPostIntegrationTests.java

@@ -290,12 +290,29 @@ public void uppercaseJsonArray() throws Exception {
 
 	@Test
 	public void uppercaseSSE() throws Exception {
-		assertThat(this.rest.exchange(RequestEntity.post(new URI("/uppercase"))
-				.accept(EVENT_STREAM).contentType(MediaType.APPLICATION_JSON)
+		String s = this.rest.exchange(RequestEntity.post(new URI("/uppercase")).contentType(MediaType.APPLICATION_JSON)
+				.body("[\"foo\",\"bar\"]"), String.class).getBody();
+		assertThat(this.rest.exchange(RequestEntity.post(new URI("/uppercase")).contentType(MediaType.APPLICATION_JSON)
 				.body("[\"foo\",\"bar\"]"), String.class).getBody())
 						.isEqualTo(sse("(FOO)", "(BAR)"));
 	}
 
+//	@Test
+//	public void uppercaseSSE() throws Exception {
+//		assertThat(this.rest.exchange(RequestEntity.post(new URI("/uppercase"))
+//				.accept(EVENT_STREAM).contentType(MediaType.APPLICATION_JSON)
+//				.body("[\"foo\",\"bar\"]"), String.class).getBody())
+//						.isEqualTo(sse("(FOO)", "(BAR)"));
+//
+////		String body = this.rest.exchange(RequestEntity.post(new URI("/uppercase")).contentType(MediaType.APPLICATION_JSON)
+////				.body("[\"foo\",\"bar\"]"), String.class).getBody();
+//
+////		System.out.println(body);
+//
+////		assertThat(body)
+////						.isEqualTo(sse("(FOO)", "(BAR)"));
+//	}
+
 	@Test
 	public void sum() throws Exception {
 
@@ -334,7 +351,8 @@ public void count() throws Exception {
 	}
 
 	private String sse(String... values) {
-		return "data:" + StringUtils.arrayToDelimitedString(values, "\n\ndata:") + "\n\n";
+		//return "data:" + StringUtils.arrayToDelimitedString(values, "\n\ndata:") + "\n\n";
+		return "[\"" + StringUtils.arrayToDelimitedString(values, "\",\"") + "\"]";
 	}
 
 	@EnableAutoConfiguration