GH-3154: Support UriBuilderFactory.EncodingMode (#3162)

* GH-3154: Support `UriBuilderFactory.EncodingMode`

Fixes https://github.com/spring-projects/spring-integration/issues/3154

Spring Framework now provides a `DefaultUriBuilderFactory.EncodingMode`
for encoding URIs in the `RestTemplate` before and after uri template
enrichment with uri variables.
Therefore `encodeUri` and manual uri variables substitution is not necessary
in Spring Integration HTTP components

* Deprecate `AbstractHttpRequestExecutingMessageHandler.encodeUri` in favor of
`DefaultUriBuilderFactory.EncodingMode` and respective configuration
on the `RestTemplate` in HTTP module and `WebClient` in WebFlux module

* * Really populate `uriFactory` into an internal `RestTemplate`
* Ensure in tests that `encoding-mode` is populated properly into an internal `RestTemplate`
* Clean up affected HTTP tests for AssertJ and JUnit 5

* * Clean up formatting

* * Apply fix for WebFlux module
* Add docs for new `encoding-mode` option

* * Remove unused import in the test

spring-integration-webflux/src/main/java/org/springframework/integration/webflux/config/WebFluxOutboundChannelAdapterParser.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -22,6 +22,7 @@ import org.springframework.beans.factory.config.RuntimeBeanReference;
 import org.springframework.beans.factory.support.BeanDefinitionBuilder;
 import org.springframework.beans.factory.xml.ParserContext;
 import org.springframework.integration.config.ExpressionFactoryBean;
+import org.springframework.integration.config.xml.IntegrationNamespaceUtils;
 import org.springframework.integration.http.config.HttpOutboundChannelAdapterParser;
 import org.springframework.integration.webflux.outbound.WebFluxRequestExecutingMessageHandler;
 import org.springframework.util.StringUtils;
@@ -52,6 +53,9 @@ public class WebFluxOutboundChannelAdapterParser extends HttpOutboundChannelAdap
 					.getConstructorArgumentValues()
 					.addIndexedArgumentValue(1, new RuntimeBeanReference(webClientRef));
 		}
+		else {
+			IntegrationNamespaceUtils.setValueIfAttributeDefined(builder, element, "encoding-mode");
+		}
 
 		String type = element.getAttribute("publisher-element-type");
 		String typeExpression = element.getAttribute("publisher-element-type-expression");

spring-integration-webflux/src/main/java/org/springframework/integration/webflux/outbound/WebFluxRequestExecutingMessageHandler.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2019 the original author or authors.
+ * Copyright 2017-2020 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.
@@ -18,7 +18,7 @@ package org.springframework.integration.webflux.outbound;
 
 import java.net.URI;
 import java.nio.charset.StandardCharsets;
-import java.util.function.Supplier;
+import java.util.Map;
 
 import org.reactivestreams.Publisher;
 
@@ -50,6 +50,7 @@ import org.springframework.web.reactive.function.BodyInserters;
 import org.springframework.web.reactive.function.client.ClientResponse;
 import org.springframework.web.reactive.function.client.WebClient;
 import org.springframework.web.reactive.function.client.WebClientResponseException;
+import org.springframework.web.util.DefaultUriBuilderFactory;
 
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
@@ -71,6 +72,8 @@ public class WebFluxRequestExecutingMessageHandler extends AbstractHttpRequestEx
 
 	private final WebClient webClient;
 
+	private final boolean webClientExplicitlySet;
+
 	private boolean replyPayloadToFlux;
 
 	private BodyExtractor<?, ClientHttpResponse> bodyExtractor;
@@ -124,10 +127,26 @@ public class WebFluxRequestExecutingMessageHandler extends AbstractHttpRequestEx
 	 */
 	public WebFluxRequestExecutingMessageHandler(Expression uriExpression, @Nullable WebClient webClient) {
 		super(uriExpression);
-		this.webClient = (webClient == null ? WebClient.create() : webClient);
+		this.webClientExplicitlySet = webClient != null;
+		this.webClient =
+				!this.webClientExplicitlySet
+						? WebClient.builder().uriBuilderFactory(this.uriFactory).build()
+						: webClient;
 		this.setAsync(true);
 	}
 
+	private void assertLocalWebClient(String option) {
+		Assert.isTrue(!this.webClientExplicitlySet,
+				() -> "The option '" + option + "' must be provided on the externally configured WebClient: "
+						+ this.webClient);
+	}
+
+	@Override
+	public void setEncodingMode(DefaultUriBuilderFactory.EncodingMode encodingMode) {
+		assertLocalWebClient("encodingMode on UriBuilderFactory");
+		super.setEncodingMode(encodingMode);
+	}
+
 	/**
 	 * The boolean flag to identify if the reply payload should be as a {@link Flux} from the response body
 	 * or as resolved value from the {@link Mono} of the response body.
@@ -185,13 +204,20 @@ public class WebFluxRequestExecutingMessageHandler extends AbstractHttpRequestEx
 	}
 
 	@Override
-	protected Object exchange(Supplier<URI> uriSupplier, HttpMethod httpMethod, HttpEntity<?> httpRequest,
-			Object expectedResponseType, Message<?> requestMessage) {
+	protected Object exchange(Object uri, HttpMethod httpMethod, HttpEntity<?> httpRequest,
+			Object expectedResponseType, Message<?> requestMessage, Map<String, ?> uriVariables) {
 
-		WebClient.RequestBodySpec requestSpec =
-				this.webClient.method(httpMethod)
-						.uri(b -> uriSupplier.get())
-						.headers(headers -> headers.putAll(httpRequest.getHeaders()));
+		WebClient.RequestBodyUriSpec requestBodyUriSpec = this.webClient.method(httpMethod);
+		WebClient.RequestBodySpec requestSpec;
+
+		if (uri instanceof URI) {
+			requestSpec = requestBodyUriSpec.uri((URI) uri);
+		}
+		else {
+			requestSpec = requestBodyUriSpec.uri((String) uri, uriVariables);
+		}
+
+		requestSpec = requestSpec.headers(headers -> headers.putAll(httpRequest.getHeaders()));
 		BodyInserter<?, ? super ClientHttpRequest> inserter = buildBodyInserterForRequest(requestMessage, httpRequest);
 		if (inserter != null) {
 			requestSpec.body(inserter);

spring-integration-webflux/src/test/java/org/springframework/integration/webflux/config/WebFluxOutboundChannelAdapterParserTests-context.xml

@@ -10,7 +10,8 @@
 
 	<si:channel id="requests"/>
 
-	<outbound-channel-adapter id="reactiveMinimalConfig" url="http://localhost/test1" channel="requests"/>
+	<outbound-channel-adapter id="reactiveMinimalConfig" url="http://localhost/test1" channel="requests"
+							  encoding-mode="VALUES_ONLY"/>
 
 	<outbound-channel-adapter id="reactiveWebClientConfig" url="http://localhost/test1" channel="requests"
 							  web-client="webClient"

spring-integration-webflux/src/test/java/org/springframework/integration/webflux/config/WebFluxOutboundChannelAdapterParserTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2019 the original author or authors.
+ * Copyright 2017-2020 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.
@@ -18,11 +18,10 @@ package org.springframework.integration.webflux.config;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
-import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
 import java.util.Date;
 
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 
 import org.springframework.beans.DirectFieldAccessor;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -33,15 +32,16 @@ import org.springframework.http.HttpMethod;
 import org.springframework.integration.endpoint.AbstractEndpoint;
 import org.springframework.integration.test.util.TestUtils;
 import org.springframework.test.annotation.DirtiesContext;
-import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
 import org.springframework.web.reactive.function.client.WebClient;
+import org.springframework.web.util.DefaultUriBuilderFactory;
 
 /**
  * @author Artem Bilan
  *
  * @since 5.0
  */
-@RunWith(SpringRunner.class)
+@SpringJUnitConfig
 @DirtiesContext
 public class WebFluxOutboundChannelAdapterParserTests {
 
@@ -75,8 +75,12 @@ public class WebFluxOutboundChannelAdapterParserTests {
 		assertThat(uriExpression.getValue()).isEqualTo("http://localhost/test1");
 		assertThat(TestUtils.getPropertyValue(handler, "httpMethodExpression", Expression.class).getExpressionString())
 				.isEqualTo(HttpMethod.POST.name());
-		assertThat(handlerAccessor.getPropertyValue("charset")).isEqualTo(Charset.forName("UTF-8"));
+		assertThat(handlerAccessor.getPropertyValue("charset")).isEqualTo(StandardCharsets.UTF_8);
 		assertThat(handlerAccessor.getPropertyValue("extractPayload")).isEqualTo(true);
+		assertThat(
+				TestUtils.getPropertyValue(handler, "webClient.uriBuilderFactory.encodingMode",
+						DefaultUriBuilderFactory.EncodingMode.class))
+				.isEqualTo(DefaultUriBuilderFactory.EncodingMode.VALUES_ONLY);
 	}
 
 	@Test