Support encoded query string in reactive requests

In addition to the updates from PR#1297 this commit adds an integration
test and fixes for the resulting failures with RxNetty, Reactor Netty,
and Undertow.

Also replaced use of URLDecoder which is not for decoding URIs with use
of UriUtils for decoding query parameters.

Issue: SPR-15140

Author: rstoyanchev

spring-web-reactive/src/test/java/org/springframework/web/reactive/result/method/annotation/RequestMappingIntegrationTests.java

@@ -60,6 +60,12 @@ public void handleWithParam() throws Exception {
 		assertEquals(expected, performGet("/param?name=George", new HttpHeaders(), String.class).getBody());
 	}
 
+	@Test // SPR-15140
+	public void handleWithEncodedParam() throws Exception {
+		String expected = "Hello  ++\u00e0!";
+		assertEquals(expected, performGet("/param?name=%20%2B+%C3%A0", new HttpHeaders(), String.class).getBody());
+	}
+
 	@Test
 	public void longStreamResult() throws Exception {
 		String[] expected = {"0", "1", "2", "3", "4"};

spring-web/src/main/java/org/springframework/http/server/reactive/AbstractServerHttpRequest.java

@@ -16,9 +16,7 @@
 
 package org.springframework.http.server.reactive;
 
-import java.io.UnsupportedEncodingException;
 import java.net.URI;
-import java.net.URLDecoder;
 import java.nio.charset.StandardCharsets;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
@@ -29,6 +27,7 @@
 import org.springframework.util.LinkedMultiValueMap;
 import org.springframework.util.MultiValueMap;
 import org.springframework.util.StringUtils;
+import org.springframework.web.util.UriUtils;
 
 /**
  * Common base class for {@link ServerHttpRequest} implementations.
@@ -79,22 +78,6 @@ public MultiValueMap<String, String> getQueryParams() {
 		return this.queryParams;
 	}
 
-	/**
-	 * A method for decoding name and value string in a name-value pair.
-	 * <p>Note that the plus sign "+" is converted into a space character " ".</p>
-	 * @param encodedString the string to be decoded
-	 * @return the decoded string
-	 * @see java.net.URLDecoder#decode(String, String)
-	 */
-	private static String decodeQueryParam(final String encodedString) {
-		try {
-			return URLDecoder.decode(encodedString, StandardCharsets.UTF_8.name());
-		} catch (UnsupportedEncodingException e) {
-			// StandardCharsets are guaranteed to be available on every implementation of the Java platform, so this should never happen.
-			throw new IllegalStateException(e);
-		}
-	}
-
 	/**
 	 * A method for parsing of the query into name-value pairs. The return
 	 * value is turned into an immutable map and cached.
@@ -113,13 +96,16 @@ protected MultiValueMap<String, String> initQueryParams() {
 				String eq = matcher.group(2);
 				String value = matcher.group(3);
 				value = (value != null ? value : (StringUtils.hasLength(eq) ? "" : null));
-				queryParams.add(decodeQueryParam(name),
-						value != null ? decodeQueryParam(value) : null);
+				queryParams.add(decodeQueryParam(name), decodeQueryParam(value));
 			}
 		}
 		return queryParams;
 	}
 
+	private static String decodeQueryParam(String value) {
+		return (value != null ? UriUtils.decode(value, StandardCharsets.UTF_8) : null);
+	}
+
 	@Override
 	public MultiValueMap<String, HttpCookie> getCookies() {
 		if (this.cookies == null) {

spring-web/src/main/java/org/springframework/http/server/reactive/ReactorServerHttpRequest.java

@@ -56,20 +56,17 @@ public ReactorServerHttpRequest(HttpServerRequest request, NettyDataBufferFactor
 
 	private static URI initUri(HttpServerRequest channel) {
 		Assert.notNull("'channel' must not be null");
+		InetSocketAddress address = channel.remoteAddress();
+		return (address == null ? URI.create(channel.uri()) : getBaseUrl(address).resolve(channel.uri()));
+	}
+
+	private static URI getBaseUrl(InetSocketAddress address) {
 		try {
-			URI uri = new URI(channel.uri());
-			InetSocketAddress remoteAddress = channel.remoteAddress();
-			return new URI(
-					uri.getScheme(),
-					uri.getUserInfo(),
-					(remoteAddress != null ? remoteAddress.getHostString() : null),
-					(remoteAddress != null ? remoteAddress.getPort() : -1),
-					uri.getPath(),
-					uri.getQuery(),
-					uri.getFragment());
+			return new URI(null, null, address.getHostString(), address.getPort(), null, null, null);
 		}
 		catch (URISyntaxException ex) {
-			throw new IllegalStateException("Could not get URI: " + ex.getMessage(), ex);
+			// Should not happen...
+			throw new IllegalStateException(ex);
 		}
 	}
 

spring-web/src/main/java/org/springframework/http/server/reactive/RxNettyServerHttpRequest.java

@@ -63,25 +63,20 @@ public RxNettyServerHttpRequest(HttpServerRequest<ByteBuf> request,
 
 	private static URI initUri(HttpServerRequest<ByteBuf> request) {
 		Assert.notNull("'request', request must not be null");
+		return StringUtils.isEmpty(request.getHostHeader()) ?
+				URI.create(request.getUri()) : getBaseUrl(request).resolve(request.getUri());
+	}
+
+	private static URI getBaseUrl(HttpServerRequest<ByteBuf> request) {
+		HttpHeaders headers = new HttpHeaders();
+		headers.add("Host", request.getHostHeader());
+		InetSocketAddress address = headers.getHost();
 		try {
-			URI uri = new URI(request.getUri());
-			InetSocketAddress remoteAddress = null;
-			if (!StringUtils.isEmpty(request.getHostHeader())) {
-				HttpHeaders headers = new HttpHeaders();
-				headers.add("Host", request.getHostHeader());
-				remoteAddress = headers.getHost();
-			}
-			return new URI(
-					uri.getScheme(),
-					uri.getUserInfo(),
-					(remoteAddress != null ? remoteAddress.getHostString() : null),
-					(remoteAddress != null ? remoteAddress.getPort() : -1),
-					uri.getPath(),
-					uri.getQuery(),
-					uri.getFragment());
+			return new URI(null, null, address.getHostString(), address.getPort(), null, null, null);
 		}
 		catch (URISyntaxException ex) {
-			throw new IllegalStateException("Could not get URI: " + ex.getMessage(), ex);
+			// Should not happen...
+			throw new IllegalStateException(ex);
 		}
 	}
 

spring-web/src/main/java/org/springframework/http/server/reactive/UndertowServerHttpRequest.java

@@ -63,11 +63,19 @@ public UndertowServerHttpRequest(HttpServerExchange exchange, DataBufferFactory
 
 	private static URI initUri(HttpServerExchange exchange) {
 		Assert.notNull(exchange, "HttpServerExchange is required.");
+		String requestURI = exchange.getRequestURI();
+		String query = exchange.getQueryString();
+		String requestUriAndQuery = StringUtils.isEmpty(query) ? requestURI : requestURI + "?" + query;
+		return (exchange.isHostIncludedInRequestURI()) ?
+				URI.create(requestUriAndQuery) : getBaseUri(exchange).resolve(requestUriAndQuery);
+	}
+
+	private static URI getBaseUri(HttpServerExchange exchange) {
 		try {
-			String query = exchange.getQueryString();
-			return new URI(exchange.getRequestScheme(), null,
-					exchange.getHostName(), exchange.getHostPort(),
-					exchange.getRequestURI(), StringUtils.hasText(query) ? query : null, null);
+			String scheme = exchange.getRequestScheme();
+			String host = exchange.getHostName();
+			int port = exchange.getHostPort();
+			return new URI(scheme, null, host, port, null, null, null);
 		}
 		catch (URISyntaxException ex) {
 			throw new IllegalStateException("Could not get URI: " + ex.getMessage(), ex);

spring-web/src/test/java/org/springframework/http/server/reactive/ServerHttpRequestIntegrationTests.java

@@ -36,9 +36,9 @@ protected CheckRequestHandler createHttpHandler() {
 
 	@Test
 	public void checkUri() throws Exception {
-		RestTemplate restTemplate = new RestTemplate();
-		RequestEntity<Void> request = RequestEntity.post(new URI("http://localhost:" + port + "/foo?param=bar")).build();
-		ResponseEntity<Void> response = restTemplate.exchange(request, Void.class);
+		URI url = new URI("http://localhost:" + port + "/foo?param=bar");
+		RequestEntity<Void> request = RequestEntity.post(url).build();
+		ResponseEntity<Void> response = new RestTemplate().exchange(request, Void.class);
 		assertEquals(HttpStatus.OK, response.getStatusCode());
 	}
 

spring-web/src/test/java/org/springframework/http/server/reactive/ServerHttpRequestTests.java

@@ -64,11 +64,11 @@ public void queryParamsWithMulitpleValues() throws Exception {
 		assertEquals(Arrays.asList("1", "2"), params.get("a"));
 	}
 
-	@Test
-	public void queryParamsWithUrlEncodedValue() throws Exception {
+	@Test // SPR-15140
+	public void queryParamsWithEncodedValue() throws Exception {
 		MultiValueMap<String, String> params = createHttpRequest("/path?a=%20%2B+%C3%A0").getQueryParams();
 		assertEquals(1, params.size());
-		assertEquals(Collections.singletonList(" + \u00e0"), params.get("a"));
+		assertEquals(Collections.singletonList(" ++\u00e0"), params.get("a"));
 	}
 
 	@Test