Add Tests for Servlet.fn

This commit adds tests for Servlet.fn, the servlet-based version of
HandlerFunctions and RouterFunctions.

See gh-21490

spring-webmvc/src/test/java/org/springframework/web/servlet/function/DefaultEntityResponseBuilderTests.java

@@ -0,0 +1,208 @@
+/*
+ * Copyright 2002-2019 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
+ *
+ *      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.web.servlet.function;
+
+import java.io.IOException;
+import java.time.ZonedDateTime;
+import java.time.format.DateTimeFormatter;
+import java.time.temporal.ChronoUnit;
+import java.util.Collections;
+import java.util.EnumSet;
+import java.util.List;
+import java.util.Set;
+import javax.servlet.ServletException;
+import javax.servlet.http.Cookie;
+
+import org.junit.Test;
+
+import org.springframework.http.CacheControl;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.mock.web.test.MockHttpServletRequest;
+import org.springframework.mock.web.test.MockHttpServletResponse;
+import org.springframework.util.LinkedMultiValueMap;
+import org.springframework.util.MultiValueMap;
+import org.springframework.web.servlet.ModelAndView;
+
+import static org.junit.Assert.*;
+
+/**
+ * @author Arjen Poutsma
+ */
+public class DefaultEntityResponseBuilderTests {
+
+	static final ServerResponse.Context EMPTY_CONTEXT = new ServerResponse.Context() {
+		@Override
+		public List<HttpMessageConverter<?>> messageConverters() {
+			return Collections.emptyList();
+		}
+
+	};
+
+	@Test
+	public void fromObject() {
+		String body = "foo";
+		EntityResponse<String> response = EntityResponse.fromObject(body).build();
+		assertSame(body, response.entity());
+	}
+
+	@Test
+	public void status() {
+		String body = "foo";
+		EntityResponse<String> result =
+				EntityResponse.fromObject(body).status(HttpStatus.CREATED).build();
+
+		assertEquals(HttpStatus.CREATED, result.statusCode());
+	}
+
+	@Test
+	public void allow() {
+		String body = "foo";
+		EntityResponse<String> result =
+				EntityResponse.fromObject(body).allow(HttpMethod.GET).build();
+		Set<HttpMethod> expected = EnumSet.of(HttpMethod.GET);
+		assertEquals(expected, result.headers().getAllow());
+	}
+
+	@Test
+	public void contentLength() {
+		String body = "foo";
+		EntityResponse<String> result = EntityResponse.fromObject(body).contentLength(42).build();
+		assertEquals(42, result.headers().getContentLength());
+	}
+
+	@Test
+	public void contentType() {
+		String body = "foo";
+		EntityResponse<String>
+				result =
+				EntityResponse.fromObject(body).contentType(MediaType.APPLICATION_JSON).build();
+
+		assertEquals(MediaType.APPLICATION_JSON, result.headers().getContentType());
+	}
+
+	@Test
+	public void etag() {
+		String body = "foo";
+		EntityResponse<String> result = EntityResponse.fromObject(body).eTag("foo").build();
+
+		assertEquals("\"foo\"", result.headers().getETag());
+	}
+
+	@Test
+	public void lastModified() {
+		ZonedDateTime now = ZonedDateTime.now();
+		String body = "foo";
+		EntityResponse<String> result = EntityResponse.fromObject(body).lastModified(now).build();
+		long expected = now.toInstant().toEpochMilli() / 1000;
+		assertEquals(expected, result.headers().getLastModified() / 1000);
+	}
+
+	@Test
+	public void cacheControlTag() {
+		String body = "foo";
+		EntityResponse<String> result =
+				EntityResponse.fromObject(body).cacheControl(CacheControl.noCache()).build();
+		assertEquals("no-cache", result.headers().getCacheControl());
+	}
+
+	@Test
+	public void varyBy() {
+		String body = "foo";
+		EntityResponse<String> result = EntityResponse.fromObject(body).varyBy("foo").build();
+		List<String> expected = Collections.singletonList("foo");
+		assertEquals(expected, result.headers().getVary());
+	}
+
+	@Test
+	public void header() {
+		String body = "foo";
+		EntityResponse<String> result = EntityResponse.fromObject(body).header("foo", "bar").build();
+		assertEquals("bar", result.headers().getFirst("foo"));
+	}
+
+	@Test
+	public void headers() {
+		String body = "foo";
+		HttpHeaders headers = new HttpHeaders();
+		headers.set("foo", "bar");
+		EntityResponse<String> result = EntityResponse.fromObject(body).headers(headers).build();
+		assertEquals(headers, result.headers());
+	}
+
+	@Test
+	public void cookie() {
+		Cookie cookie = new Cookie("name", "value");
+		EntityResponse<String> result =
+				EntityResponse.fromObject("foo").cookie(cookie)
+						.build();
+		assertTrue(result.cookies().get("name").contains(cookie));
+	}
+
+	@Test
+	public void cookies() {
+		MultiValueMap<String, Cookie> newCookies = new LinkedMultiValueMap<>();
+		newCookies.add("name", new Cookie("name", "value"));
+		EntityResponse<String> result =
+				EntityResponse.fromObject("foo").cookies(cookies -> cookies.addAll(newCookies))
+						.build();
+		assertEquals(newCookies, result.cookies());
+	}
+
+	@Test
+	public void notModifiedEtag() throws Exception {
+		String etag = "\"foo\"";
+		EntityResponse<String> entityResponse = EntityResponse.fromObject("bar")
+				.eTag(etag)
+				.build();
+
+		MockHttpServletRequest mockRequest = new MockHttpServletRequest("GET", "http://example.com");
+		mockRequest.addHeader(HttpHeaders.IF_NONE_MATCH, etag);
+
+		MockHttpServletResponse mockResponse = new MockHttpServletResponse();
+
+		ModelAndView mav = entityResponse.writeTo(mockRequest, mockResponse, EMPTY_CONTEXT);
+		assertNull(mav);
+
+		assertEquals(HttpStatus.NOT_MODIFIED.value(), mockResponse.getStatus());
+	}
+
+
+	@Test
+	public void notModifiedLastModified() throws ServletException, IOException {
+		ZonedDateTime now = ZonedDateTime.now();
+		ZonedDateTime oneMinuteBeforeNow = now.minus(1, ChronoUnit.MINUTES);
+
+		EntityResponse<String> entityResponse = EntityResponse.fromObject("bar")
+				.lastModified(oneMinuteBeforeNow)
+				.build();
+
+		MockHttpServletRequest mockRequest = new MockHttpServletRequest("GET", "http://example.com");
+		mockRequest.addHeader(HttpHeaders.IF_MODIFIED_SINCE, DateTimeFormatter.RFC_1123_DATE_TIME.format(now));
+
+		MockHttpServletResponse mockResponse = new MockHttpServletResponse();
+
+		ModelAndView mav = entityResponse.writeTo(mockRequest, mockResponse, EMPTY_CONTEXT);
+		assertNull(mav);
+
+		assertEquals(HttpStatus.NOT_MODIFIED.value(), mockResponse.getStatus());
+	}
+
+}

spring-webmvc/src/test/java/org/springframework/web/servlet/function/DefaultRenderingResponseTests.java

@@ -0,0 +1,190 @@
+/*
+ * Copyright 2002-2019 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
+ *
+ *      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.web.servlet.function;
+
+import java.time.ZonedDateTime;
+import java.time.format.DateTimeFormatter;
+import java.time.temporal.ChronoUnit;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+import javax.servlet.http.Cookie;
+
+import org.junit.Test;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.mock.web.test.MockHttpServletRequest;
+import org.springframework.mock.web.test.MockHttpServletResponse;
+import org.springframework.util.LinkedMultiValueMap;
+import org.springframework.util.MultiValueMap;
+import org.springframework.web.servlet.ModelAndView;
+
+import static org.junit.Assert.*;
+
+/**
+ * @author Arjen Poutsma
+ */
+public class DefaultRenderingResponseTests {
+
+	static final ServerResponse.Context EMPTY_CONTEXT = new ServerResponse.Context() {
+		@Override
+		public List<HttpMessageConverter<?>> messageConverters() {
+			return Collections.emptyList();
+		}
+
+	};
+
+	@Test
+	public void create() throws Exception {
+		String name = "foo";
+		RenderingResponse result = RenderingResponse.create(name).build();
+
+		MockHttpServletRequest request = new MockHttpServletRequest();
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		ModelAndView mav = result.writeTo(request, response, EMPTY_CONTEXT);
+
+		assertEquals(name, mav.getViewName());
+	}
+
+	@Test
+	public void status() throws Exception {
+		HttpStatus status = HttpStatus.I_AM_A_TEAPOT;
+		RenderingResponse result = RenderingResponse.create("foo").status(status).build();
+
+		MockHttpServletRequest request = new MockHttpServletRequest();
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		ModelAndView mav = result.writeTo(request, response, EMPTY_CONTEXT);
+		assertNotNull(mav);
+		assertEquals(status.value(), response.getStatus());
+	}
+
+	@Test
+	public void headers() throws Exception {
+		HttpHeaders headers = new HttpHeaders();
+		headers.set("foo", "bar");
+		RenderingResponse result = RenderingResponse.create("foo").headers(headers).build();
+
+		MockHttpServletRequest request = new MockHttpServletRequest();
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		ModelAndView mav = result.writeTo(request, response, EMPTY_CONTEXT);
+		assertNotNull(mav);
+
+		assertEquals("bar", response.getHeader("foo"));
+	}
+
+	@Test
+	public void modelAttribute() throws Exception {
+		RenderingResponse result = RenderingResponse.create("foo")
+				.modelAttribute("foo", "bar").build();
+
+		MockHttpServletRequest request = new MockHttpServletRequest();
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		ModelAndView mav = result.writeTo(request, response, EMPTY_CONTEXT);
+		assertNotNull(mav);
+
+		assertEquals("bar", mav.getModel().get("foo"));
+	}
+
+
+	@Test
+	public void modelAttributeConventions() throws Exception {
+		RenderingResponse result = RenderingResponse.create("foo")
+				.modelAttribute("bar").build();
+		MockHttpServletRequest request = new MockHttpServletRequest();
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		ModelAndView mav = result.writeTo(request, response, EMPTY_CONTEXT);
+		assertNotNull(mav);
+		assertEquals("bar", mav.getModel().get("string"));
+	}
+
+	@Test
+	public void modelAttributes() throws Exception {
+		Map<String, String> model = Collections.singletonMap("foo", "bar");
+		RenderingResponse result = RenderingResponse.create("foo")
+				.modelAttributes(model).build();
+		MockHttpServletRequest request = new MockHttpServletRequest();
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		ModelAndView mav = result.writeTo(request, response, EMPTY_CONTEXT);
+		assertNotNull(mav);
+		assertEquals("bar", mav.getModel().get("foo"));
+	}
+
+	@Test
+	public void modelAttributesConventions() throws Exception {
+		RenderingResponse result = RenderingResponse.create("foo")
+				.modelAttributes("bar").build();
+		MockHttpServletRequest request = new MockHttpServletRequest();
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		ModelAndView mav = result.writeTo(request, response, EMPTY_CONTEXT);
+		assertNotNull(mav);
+		assertEquals("bar", mav.getModel().get("string"));
+	}
+
+	@Test
+	public void cookies() throws Exception {
+		MultiValueMap<String, Cookie> newCookies = new LinkedMultiValueMap<>();
+		newCookies.add("name", new Cookie("name", "value"));
+		RenderingResponse result =
+				RenderingResponse.create("foo").cookies(cookies -> cookies.addAll(newCookies)).build();
+		MockHttpServletRequest request = new MockHttpServletRequest();
+		MockHttpServletResponse response = new MockHttpServletResponse();
+		ModelAndView mav = result.writeTo(request, response, EMPTY_CONTEXT);
+		assertNotNull(mav);
+		assertEquals(1, response.getCookies().length);
+		assertEquals("name", response.getCookies()[0].getName());
+		assertEquals("value", response.getCookies()[0].getValue());
+	}
+
+	@Test
+	public void notModifiedEtag() throws Exception {
+		String etag = "\"foo\"";
+		RenderingResponse result = RenderingResponse.create("bar")
+				.header(HttpHeaders.ETAG, etag)
+				.build();
+
+		MockHttpServletRequest request = new MockHttpServletRequest("GET", "http://example.com");
+		request.addHeader(HttpHeaders.IF_NONE_MATCH, etag);
+		MockHttpServletResponse response = new MockHttpServletResponse();
+
+		ModelAndView mav = result.writeTo(request, response, EMPTY_CONTEXT);
+		assertNull(mav);
+		assertEquals(HttpStatus.NOT_MODIFIED.value(), response.getStatus());
+	}
+
+
+	@Test
+	public void notModifiedLastModified() throws Exception {
+		ZonedDateTime now = ZonedDateTime.now();
+		ZonedDateTime oneMinuteBeforeNow = now.minus(1, ChronoUnit.MINUTES);
+
+		RenderingResponse result = RenderingResponse.create("bar")
+				.header(HttpHeaders.LAST_MODIFIED, DateTimeFormatter.RFC_1123_DATE_TIME.format(oneMinuteBeforeNow))
+				.build();
+
+		MockHttpServletRequest request = new MockHttpServletRequest("GET", "http://example.com");
+		request.addHeader(HttpHeaders.IF_MODIFIED_SINCE,DateTimeFormatter.RFC_1123_DATE_TIME.format(now));
+		MockHttpServletResponse response = new MockHttpServletResponse();
+
+		ModelAndView mav = result.writeTo(request, response, EMPTY_CONTEXT);
+		assertNull(mav);
+		assertEquals(HttpStatus.NOT_MODIFIED.value(), response.getStatus());
+	}
+
+
+}

spring-webmvc/src/test/java/org/springframework/web/servlet/function/DefaultServerRequestBuilderTests.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright 2002-2019 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
+ *
+ *      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.web.servlet.function;
+
+import java.io.IOException;
+import java.util.Collections;
+import java.util.List;
+import javax.servlet.ServletException;
+import javax.servlet.http.Cookie;
+
+import org.junit.Test;
+
+import org.springframework.http.HttpMethod;
+import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.http.converter.StringHttpMessageConverter;
+import org.springframework.mock.web.test.MockHttpServletRequest;
+
+import static org.junit.Assert.*;
+
+/**
+ * @author Arjen Poutsma
+ */
+public class DefaultServerRequestBuilderTests {
+
+	private final List<HttpMessageConverter<?>> messageConverters = Collections.singletonList(
+			new StringHttpMessageConverter());
+
+	@Test
+	public void from() throws ServletException, IOException {
+		MockHttpServletRequest request = new MockHttpServletRequest("POST", "http://example.com");
+		request.addHeader("foo", "bar");
+
+		ServerRequest other = ServerRequest.create(request, messageConverters);
+
+		ServerRequest result = ServerRequest.from(other)
+				.method(HttpMethod.HEAD)
+				.header("foo", "bar")
+				.headers(httpHeaders -> httpHeaders.set("baz", "qux"))
+				.cookie("foo", "bar")
+				.cookies(cookies -> cookies.set("baz", new Cookie("baz", "qux")))
+				.attribute("foo", "bar")
+				.attributes(attributes -> attributes.put("baz", "qux"))
+				.body("baz")
+				.build();
+
+		assertEquals(HttpMethod.HEAD, result.method());
+		assertEquals(2, result.headers().asHttpHeaders().size());
+		assertEquals("bar", result.headers().asHttpHeaders().getFirst("foo"));
+		assertEquals("qux", result.headers().asHttpHeaders().getFirst("baz"));
+		assertEquals(2, result.cookies().size());
+		assertEquals("bar", result.cookies().getFirst("foo").getValue());
+		assertEquals("qux", result.cookies().getFirst("baz").getValue());
+		assertEquals(2, result.attributes().size());
+		assertEquals("bar", result.attributes().get("foo"));
+		assertEquals("qux", result.attributes().get("baz"));
+
+		String body = result.body(String.class);
+		assertEquals("baz", body);
+	}
+
+
+}

spring-webmvc/src/test/java/org/springframework/web/servlet/function/DefaultServerRequestTests.java

@@ -0,0 +1,296 @@
+/*
+ * Copyright 2002-2019 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
+ *
+ *      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.web.servlet.function;
+
+import java.net.InetSocketAddress;
+import java.net.URI;
+import java.nio.charset.Charset;
+import java.security.Principal;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.OptionalLong;
+import javax.servlet.http.Cookie;
+
+import org.junit.Test;
+
+import org.springframework.core.ParameterizedTypeReference;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.HttpRange;
+import org.springframework.http.MediaType;
+import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.http.converter.StringHttpMessageConverter;
+import org.springframework.mock.web.test.MockHttpServletRequest;
+import org.springframework.mock.web.test.MockHttpSession;
+import org.springframework.util.LinkedMultiValueMap;
+import org.springframework.util.MultiValueMap;
+import org.springframework.web.HttpMediaTypeNotSupportedException;
+
+import static java.nio.charset.StandardCharsets.UTF_8;
+import static org.junit.Assert.*;
+
+/**
+ * @author Arjen Poutsma
+ * @since 5.1
+ */
+public class DefaultServerRequestTests {
+
+	private final List<HttpMessageConverter<?>> messageConverters = Collections.singletonList(
+			new StringHttpMessageConverter());
+
+	@Test
+	public void method() {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("HEAD", "/");
+		DefaultServerRequest request =
+				new DefaultServerRequest(servletRequest, this.messageConverters);
+
+		assertEquals(HttpMethod.HEAD, request.method());
+	}
+
+	@Test
+	public void uri() {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/");
+		servletRequest.setServerName("example.com");
+		servletRequest.setScheme("https");
+		servletRequest.setServerPort(443);
+
+		DefaultServerRequest request =
+				new DefaultServerRequest(servletRequest, this.messageConverters);
+
+		assertEquals(URI.create("https://example.com/"), request.uri());
+	}
+
+	@Test
+	public void uriBuilder() {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/path");
+		servletRequest.setQueryString("a=1");
+
+		DefaultServerRequest request =
+				new DefaultServerRequest(servletRequest, this.messageConverters);
+
+		URI result = request.uriBuilder().build();
+		assertEquals("http", result.getScheme());
+		assertEquals("localhost", result.getHost());
+		assertEquals(-1, result.getPort());
+		assertEquals("/path", result.getPath());
+		assertEquals("a=1", result.getQuery());
+	}
+
+	@Test
+	public void attribute() {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/");
+		servletRequest.setAttribute("foo", "bar");
+
+		DefaultServerRequest request =
+				new DefaultServerRequest(servletRequest, this.messageConverters);
+
+		assertEquals(Optional.of("bar"), request.attribute("foo"));
+	}
+
+	@Test
+	public void params() {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/");
+		servletRequest.setParameter("foo", "bar");
+
+		DefaultServerRequest request =
+				new DefaultServerRequest(servletRequest, this.messageConverters);
+
+		assertEquals(Optional.of("bar"), request.param("foo"));
+	}
+
+	@Test
+	public void emptyQueryParam() {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/");
+		servletRequest.setParameter("foo", "");
+
+		DefaultServerRequest request =
+				new DefaultServerRequest(servletRequest, this.messageConverters);
+
+		assertEquals(Optional.of(""), request.param("foo"));
+	}
+
+	@Test
+	public void absentQueryParam() {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/");
+		servletRequest.setParameter("foo", "");
+
+		DefaultServerRequest request =
+				new DefaultServerRequest(servletRequest, this.messageConverters);
+
+		assertEquals(Optional.empty(), request.param("bar"));
+	}
+
+	@Test
+	public void pathVariable() {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/");
+		Map<String, String> pathVariables = Collections.singletonMap("foo", "bar");
+		servletRequest
+				.setAttribute(RouterFunctions.URI_TEMPLATE_VARIABLES_ATTRIBUTE, pathVariables);
+
+		DefaultServerRequest request = new DefaultServerRequest(servletRequest,
+				this.messageConverters);
+
+		assertEquals("bar", request.pathVariable("foo"));
+	}
+
+	@Test(expected = IllegalArgumentException.class)
+	public void pathVariableNotFound() {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/");
+		Map<String, String> pathVariables = Collections.singletonMap("foo", "bar");
+		servletRequest
+				.setAttribute(RouterFunctions.URI_TEMPLATE_VARIABLES_ATTRIBUTE, pathVariables);
+
+		DefaultServerRequest request = new DefaultServerRequest(servletRequest,
+				this.messageConverters);
+
+		request.pathVariable("baz");
+	}
+
+	@Test
+	public void pathVariables() {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/");
+		Map<String, String> pathVariables = Collections.singletonMap("foo", "bar");
+		servletRequest
+				.setAttribute(RouterFunctions.URI_TEMPLATE_VARIABLES_ATTRIBUTE, pathVariables);
+
+		DefaultServerRequest request = new DefaultServerRequest(servletRequest,
+				this.messageConverters);
+
+		assertEquals(pathVariables, request.pathVariables());
+	}
+
+	@Test
+	public void header() {
+		HttpHeaders httpHeaders = new HttpHeaders();
+		List<MediaType> accept =
+				Collections.singletonList(MediaType.APPLICATION_JSON);
+		httpHeaders.setAccept(accept);
+		List<Charset> acceptCharset = Collections.singletonList(UTF_8);
+		httpHeaders.setAcceptCharset(acceptCharset);
+		long contentLength = 42L;
+		httpHeaders.setContentLength(contentLength);
+		MediaType contentType = MediaType.TEXT_PLAIN;
+		httpHeaders.setContentType(contentType);
+		InetSocketAddress host = InetSocketAddress.createUnresolved("localhost", 80);
+		httpHeaders.setHost(host);
+		List<HttpRange> range = Collections.singletonList(HttpRange.createByteRange(0, 42));
+		httpHeaders.setRange(range);
+
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/");
+		httpHeaders.forEach(servletRequest::addHeader);
+		servletRequest.setContentType(MediaType.TEXT_PLAIN_VALUE);
+
+		DefaultServerRequest request = new DefaultServerRequest(servletRequest,
+				this.messageConverters);
+
+		ServerRequest.Headers headers = request.headers();
+		assertEquals(accept, headers.accept());
+		assertEquals(acceptCharset, headers.acceptCharset());
+		assertEquals(OptionalLong.of(contentLength), headers.contentLength());
+		assertEquals(Optional.of(contentType), headers.contentType());
+		assertEquals(httpHeaders, headers.asHttpHeaders());
+	}
+
+	@Test
+	public void cookies() {
+		Cookie cookie = new Cookie("foo", "bar");
+
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/");
+		servletRequest.setCookies(cookie);
+
+		DefaultServerRequest request = new DefaultServerRequest(servletRequest,
+				this.messageConverters);
+
+		MultiValueMap<String, Cookie> expected = new LinkedMultiValueMap<>();
+		expected.add("foo", cookie);
+
+		assertEquals(expected, request.cookies());
+
+	}
+
+	@Test
+	public void bodyClass() throws Exception {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/");
+		servletRequest.setContentType(MediaType.TEXT_PLAIN_VALUE);
+		servletRequest.setContent("foo".getBytes(UTF_8));
+
+		DefaultServerRequest request = new DefaultServerRequest(servletRequest,
+				this.messageConverters);
+
+		String result = request.body(String.class);
+		assertEquals("foo", result);
+	}
+
+	@Test
+	public void bodyParameterizedTypeReference() throws Exception {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/");
+		servletRequest.setContentType(MediaType.TEXT_PLAIN_VALUE);
+		servletRequest.setContent("foo".getBytes(UTF_8));
+
+		DefaultServerRequest request = new DefaultServerRequest(servletRequest,
+				this.messageConverters);
+
+		String result = request.body(new ParameterizedTypeReference<String>() {});
+		assertEquals("foo", result);
+	}
+
+	@Test(expected = HttpMediaTypeNotSupportedException.class)
+	public void bodyUnacceptable() throws Exception {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/");
+		servletRequest.setContentType(MediaType.TEXT_PLAIN_VALUE);
+		servletRequest.setContent("foo".getBytes(UTF_8));
+
+		DefaultServerRequest request =
+				new DefaultServerRequest(servletRequest, Collections.emptyList());
+
+		request.body(String.class);
+	}
+
+	@Test
+	public void session() {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/");
+		MockHttpSession session = new MockHttpSession();
+		servletRequest.setSession(session);
+
+		DefaultServerRequest request = new DefaultServerRequest(servletRequest,
+				this.messageConverters);
+
+		assertEquals(session, request.session());
+
+	}
+
+	@Test
+	public void principal() {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/");
+		Principal principal = new Principal() {
+			@Override
+			public String getName() {
+				return "foo";
+			}
+		};
+		servletRequest.setUserPrincipal(principal);
+
+		DefaultServerRequest request = new DefaultServerRequest(servletRequest,
+				this.messageConverters);
+
+		assertEquals(principal, request.principal().get());
+
+	}
+
+}

spring-webmvc/src/test/java/org/springframework/web/servlet/function/DefaultServerResponseBuilderTests.java

@@ -0,0 +1,327 @@
+/*
+ * Copyright 2002-2019 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
+ *
+ *      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.web.servlet.function;
+
+import java.net.URI;
+import java.time.ZonedDateTime;
+import java.time.format.DateTimeFormatter;
+import java.time.temporal.ChronoUnit;
+import java.util.Collections;
+import java.util.EnumSet;
+import java.util.List;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionStage;
+import javax.servlet.http.Cookie;
+
+import org.junit.Test;
+import org.reactivestreams.Publisher;
+import reactor.core.publisher.Mono;
+
+import org.springframework.http.CacheControl;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.http.converter.StringHttpMessageConverter;
+import org.springframework.mock.web.test.MockHttpServletRequest;
+import org.springframework.mock.web.test.MockHttpServletResponse;
+import org.springframework.util.LinkedMultiValueMap;
+import org.springframework.util.MultiValueMap;
+import org.springframework.web.servlet.ModelAndView;
+
+import static org.junit.Assert.*;
+
+/**
+ * @author Arjen Poutsma
+ */
+public class DefaultServerResponseBuilderTests {
+
+	static final ServerResponse.Context EMPTY_CONTEXT = new ServerResponse.Context() {
+		@Override
+		public List<HttpMessageConverter<?>> messageConverters() {
+			return Collections.emptyList();
+
+		}
+
+	};
+
+	@Test
+	public void status() {
+		ServerResponse response = ServerResponse.status(HttpStatus.CREATED).build();
+		assertEquals(HttpStatus.CREATED, response.statusCode());
+	}
+
+	@Test
+	public void from() {
+		ServerResponse other = ServerResponse.ok().header("foo", "bar").build();
+		ServerResponse result = ServerResponse.from(other).build();
+		assertEquals(HttpStatus.OK, result.statusCode());
+		assertEquals("bar", result.headers().getFirst("foo"));
+	}
+
+
+	@Test
+	public void ok() {
+		ServerResponse response = ServerResponse.ok().build();
+
+		assertEquals(HttpStatus.OK, response.statusCode());
+	}
+
+	@Test
+	public void created() {
+		URI location = URI.create("http://example.com");
+		ServerResponse response = ServerResponse.created(location).build();
+		assertEquals(HttpStatus.CREATED, response.statusCode());
+		assertEquals(location, response.headers().getLocation());
+	}
+
+	@Test
+	public void accepted() {
+		ServerResponse response = ServerResponse.accepted().build();
+		assertEquals(HttpStatus.ACCEPTED, response.statusCode());
+	}
+
+	@Test
+	public void noContent() {
+		ServerResponse response = ServerResponse.noContent().build();
+		assertEquals(HttpStatus.NO_CONTENT, response.statusCode());
+	}
+
+	@Test
+	public void seeOther() {
+		URI location = URI.create("http://example.com");
+		ServerResponse response = ServerResponse.seeOther(location).build();
+		assertEquals(HttpStatus.SEE_OTHER, response.statusCode());
+		assertEquals(location, response.headers().getLocation());
+	}
+
+	@Test
+	public void temporaryRedirect() {
+		URI location = URI.create("http://example.com");
+		ServerResponse response = ServerResponse.temporaryRedirect(location).build();
+		assertEquals(HttpStatus.TEMPORARY_REDIRECT, response.statusCode());
+		assertEquals(location, response.headers().getLocation());
+	}
+
+	@Test
+	public void permanentRedirect() {
+		URI location = URI.create("http://example.com");
+		ServerResponse response = ServerResponse.permanentRedirect(location).build();
+		assertEquals(HttpStatus.PERMANENT_REDIRECT, response.statusCode());
+		assertEquals(location, response.headers().getLocation());
+	}
+
+	@Test
+	public void badRequest() {
+		ServerResponse response = ServerResponse.badRequest().build();
+		assertEquals(HttpStatus.BAD_REQUEST, response.statusCode());
+	}
+
+	@Test
+	public void notFound() {
+		ServerResponse response = ServerResponse.notFound().build();
+		assertEquals(HttpStatus.NOT_FOUND, response.statusCode());
+	}
+
+	@Test
+	public void unprocessableEntity() {
+		ServerResponse response = ServerResponse.unprocessableEntity().build();
+		assertEquals(HttpStatus.UNPROCESSABLE_ENTITY, response.statusCode());
+	}
+
+	@Test
+	public void allow() {
+		ServerResponse response = ServerResponse.ok().allow(HttpMethod.GET).build();
+		assertEquals(EnumSet.of(HttpMethod.GET), response.headers().getAllow());
+	}
+
+	@Test
+	public void contentLength() {
+		ServerResponse response = ServerResponse.ok().contentLength(42).build();
+		assertEquals(42L, response.headers().getContentLength());
+	}
+
+	@Test
+	public void contentType() {
+		ServerResponse response = ServerResponse.ok().contentType(MediaType.APPLICATION_JSON).build();
+		assertEquals(MediaType.APPLICATION_JSON, response.headers().getContentType());
+	}
+
+	@Test
+	public void eTag() {
+		ServerResponse response = ServerResponse.ok().eTag("foo").build();
+		assertEquals("\"foo\"", response.headers().getETag());
+	}
+
+	@Test
+	public void lastModified() {
+		ZonedDateTime now = ZonedDateTime.now();
+		ServerResponse response = ServerResponse.ok().lastModified(now).build();
+		long expected = now.toInstant().toEpochMilli() / 1000;
+		assertEquals(expected, response.headers().getLastModified() / 1000);
+	}
+
+	@Test
+	public void cacheControlTag() {
+		ServerResponse response = ServerResponse.ok().cacheControl(CacheControl.noCache()).build();
+		assertEquals("no-cache", response.headers().getCacheControl());
+	}
+
+	@Test
+	public void varyBy() {
+		ServerResponse response = ServerResponse.ok().varyBy("foo").build();
+		List<String> expected = Collections.singletonList("foo");
+		assertEquals(expected, response.headers().getVary());
+	}
+
+
+	@Test
+	public void statusCode() {
+		HttpStatus statusCode = HttpStatus.ACCEPTED;
+		ServerResponse response = ServerResponse.status(statusCode).build();
+		assertEquals(statusCode, response.statusCode());
+	}
+
+	@Test
+	public void headers() {
+		HttpHeaders newHeaders = new HttpHeaders();
+		newHeaders.set("foo", "bar");
+		ServerResponse response = ServerResponse.ok()
+				.headers(headers -> headers.addAll(newHeaders))
+				.build();
+		assertEquals(newHeaders, response.headers());
+	}
+
+	@Test
+	public void cookies() {
+		MultiValueMap<String, Cookie> newCookies = new LinkedMultiValueMap<>();
+		newCookies.add("name", new Cookie("name", "value"));
+		ServerResponse response = ServerResponse.ok()
+				.cookies(cookies -> cookies.addAll(newCookies))
+				.build();
+		assertEquals(newCookies, response.cookies());
+	}
+
+	@Test
+	public void build() throws Exception {
+		Cookie cookie = new Cookie("name", "value");
+		ServerResponse response = ServerResponse.status(HttpStatus.CREATED)
+				.header("MyKey", "MyValue")
+				.cookie(cookie)
+				.build();
+
+		MockHttpServletRequest mockRequest = new MockHttpServletRequest("GET", "http://example.com");
+		MockHttpServletResponse mockResponse = new MockHttpServletResponse();
+
+		ModelAndView mav = response.writeTo(mockRequest, mockResponse, EMPTY_CONTEXT);
+		assertNull(mav);
+
+		assertEquals(HttpStatus.CREATED.value(), mockResponse.getStatus());
+		assertEquals("MyValue", mockResponse.getHeader("MyKey"));
+		assertEquals("value", mockResponse.getCookie("name").getValue());
+	}
+
+	@Test
+	public void notModifiedEtag() throws Exception {
+		String etag = "\"foo\"";
+		ServerResponse response = ServerResponse.ok()
+				.eTag(etag)
+				.body("bar");
+
+		MockHttpServletRequest mockRequest = new MockHttpServletRequest("GET", "http://example.com");
+		mockRequest.addHeader(HttpHeaders.IF_NONE_MATCH, etag);
+
+		MockHttpServletResponse mockResponse = new MockHttpServletResponse();
+		ModelAndView mav = response.writeTo(mockRequest, mockResponse, EMPTY_CONTEXT);
+		assertNull(mav);
+
+		assertEquals(HttpStatus.NOT_MODIFIED.value(), mockResponse.getStatus());
+	}
+
+	@Test
+	public void notModifiedLastModified() throws Exception {
+		ZonedDateTime now = ZonedDateTime.now();
+		ZonedDateTime oneMinuteBeforeNow = now.minus(1, ChronoUnit.MINUTES);
+
+		ServerResponse response = ServerResponse.ok()
+				.lastModified(oneMinuteBeforeNow)
+				.body("bar");
+
+		MockHttpServletRequest mockRequest = new MockHttpServletRequest("GET", "http://example.com");
+		mockRequest.addHeader(HttpHeaders.IF_MODIFIED_SINCE, DateTimeFormatter.RFC_1123_DATE_TIME.format(now));
+
+		MockHttpServletResponse mockResponse = new MockHttpServletResponse();
+		ModelAndView mav = response.writeTo(mockRequest, mockResponse, EMPTY_CONTEXT);
+		assertNull(mav);
+
+		assertEquals(HttpStatus.NOT_MODIFIED.value(), mockResponse.getStatus());
+	}
+
+	@Test
+	public void body() throws Exception {
+		String body = "foo";
+		ServerResponse response = ServerResponse.ok().body(body);
+
+		MockHttpServletRequest mockRequest = new MockHttpServletRequest("GET", "http://example.com");
+		MockHttpServletResponse mockResponse = new MockHttpServletResponse();
+		ServerResponse.Context context = () -> Collections.singletonList(new StringHttpMessageConverter());
+
+		ModelAndView mav = response.writeTo(mockRequest, mockResponse, context);
+		assertNull(mav);
+
+		assertEquals(body, mockResponse.getContentAsString());
+	}
+
+	@Test
+	public void asyncBodyCompletionStage() throws Exception {
+		String body = "foo";
+		CompletionStage<String> completionStage = CompletableFuture.completedFuture(body);
+		ServerResponse response = ServerResponse.ok().asyncBody(completionStage);
+
+		MockHttpServletRequest mockRequest = new MockHttpServletRequest("GET", "http://example.com");
+		MockHttpServletResponse mockResponse = new MockHttpServletResponse();
+		mockRequest.setAsyncSupported(true);
+
+		ServerResponse.Context context = () -> Collections.singletonList(new StringHttpMessageConverter());
+
+		ModelAndView mav = response.writeTo(mockRequest, mockResponse, context);
+		assertNull(mav);
+
+
+		assertEquals(body, mockResponse.getContentAsString());
+	}
+
+	@Test
+	public void asyncBodyPublisher() throws Exception {
+		String body = "foo";
+		Publisher<String> publisher = Mono.just(body);
+		ServerResponse response = ServerResponse.ok().asyncBody(publisher);
+
+		MockHttpServletRequest mockRequest = new MockHttpServletRequest("GET", "http://example.com");
+		MockHttpServletResponse mockResponse = new MockHttpServletResponse();
+		mockRequest.setAsyncSupported(true);
+
+		ServerResponse.Context context = () -> Collections.singletonList(new StringHttpMessageConverter());
+
+		ModelAndView mav = response.writeTo(mockRequest, mockResponse, context);
+		assertNull(mav);
+
+		assertEquals(body, mockResponse.getContentAsString());
+	}
+
+}

spring-webmvc/src/test/java/org/springframework/web/servlet/function/PathResourceLookupFunctionTests.java

@@ -0,0 +1,120 @@
+/*
+ * Copyright 2002-2019 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
+ *
+ *      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.web.servlet.function;
+
+import java.io.File;
+import java.util.Collections;
+import java.util.Optional;
+import java.util.function.Function;
+
+import org.junit.Test;
+
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.core.io.Resource;
+import org.springframework.mock.web.test.MockHttpServletRequest;
+
+import static org.junit.Assert.*;
+
+/**
+ * @author Arjen Poutsma
+ */
+public class PathResourceLookupFunctionTests {
+
+	@Test
+	public void normal() throws Exception {
+		ClassPathResource location =
+				new ClassPathResource("org/springframework/web/servlet/function/");
+
+		PathResourceLookupFunction function =
+				new PathResourceLookupFunction("/resources/**", location);
+
+		MockHttpServletRequest servletRequest =
+				new MockHttpServletRequest("GET", "/resources/response.txt");
+		ServerRequest request = new DefaultServerRequest(servletRequest, Collections.emptyList());
+
+		Optional<Resource> result = function.apply(request);
+		assertTrue(result.isPresent());
+
+		File expected = new ClassPathResource("response.txt", getClass()).getFile();
+		assertEquals(expected, result.get().getFile());
+	}
+
+	@Test
+	public void subPath() throws Exception {
+		ClassPathResource location =
+				new ClassPathResource("org/springframework/web/servlet/function/");
+
+		PathResourceLookupFunction function =
+				new PathResourceLookupFunction("/resources/**", location);
+
+		MockHttpServletRequest servletRequest =
+				new MockHttpServletRequest("GET", "/resources/child/response.txt");
+		ServerRequest request = new DefaultServerRequest(servletRequest, Collections.emptyList());
+
+		Optional<Resource> result = function.apply(request);
+		assertTrue(result.isPresent());
+
+		File expected =
+				new ClassPathResource("org/springframework/web/servlet/function/child/response.txt")
+						.getFile();
+		assertEquals(expected, result.get().getFile());
+	}
+
+	@Test
+	public void notFound() {
+		ClassPathResource location =
+				new ClassPathResource("org/springframework/web/reactive/function/server/");
+
+		PathResourceLookupFunction function =
+				new PathResourceLookupFunction("/resources/**", location);
+
+		MockHttpServletRequest servletRequest =
+				new MockHttpServletRequest("GET", "/resources/foo.txt");
+		ServerRequest request = new DefaultServerRequest(servletRequest, Collections.emptyList());
+
+		Optional<Resource> result = function.apply(request);
+		assertFalse(result.isPresent());
+	}
+
+	@Test
+	public void composeResourceLookupFunction() throws Exception {
+		ClassPathResource defaultResource = new ClassPathResource("response.txt", getClass());
+
+		Function<ServerRequest, Optional<Resource>> lookupFunction =
+				new PathResourceLookupFunction("/resources/**",
+						new ClassPathResource("org/springframework/web/servlet/function/"));
+
+		Function<ServerRequest, Optional<Resource>> customLookupFunction =
+				lookupFunction.andThen((Optional<Resource> optionalResource) -> {
+					if (optionalResource.isPresent()) {
+						return optionalResource;
+					}
+					else {
+						return Optional.of(defaultResource);
+					}
+				});
+
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/resources/foo");
+		ServerRequest request = new DefaultServerRequest(servletRequest, Collections.emptyList());
+
+		Optional<Resource> result = customLookupFunction.apply(request);
+		assertTrue(result.isPresent());
+
+		assertEquals(defaultResource.getFile(), result.get().getFile());
+	}
+
+}

spring-webmvc/src/test/java/org/springframework/web/servlet/function/RequestPredicateTests.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright 2002-2019 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
+ *
+ *      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.web.servlet.function;
+
+import java.util.Collections;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import org.springframework.mock.web.test.MockHttpServletRequest;
+
+import static org.junit.Assert.*;
+
+/**
+ * @author Arjen Poutsma
+ */
+public class RequestPredicateTests {
+
+	private ServerRequest request;
+
+	@Before
+	public void createRequest() {
+		this.request = new DefaultServerRequest(new MockHttpServletRequest(),
+				Collections.emptyList());
+	}
+
+	@Test
+	public void and() {
+		RequestPredicate predicate1 = request -> true;
+		RequestPredicate predicate2 = request -> true;
+		RequestPredicate predicate3 = request -> false;
+
+		assertTrue(predicate1.and(predicate2).test(request));
+		assertTrue(predicate2.and(predicate1).test(request));
+		assertFalse(predicate1.and(predicate3).test(request));
+	}
+
+	@Test
+	public void negate() {
+		RequestPredicate predicate = request -> false;
+		RequestPredicate negated = predicate.negate();
+
+		assertTrue(negated.test(request));
+
+		predicate = request -> true;
+		negated = predicate.negate();
+
+		assertFalse(negated.test(request));
+	}
+
+	@Test
+	public void or() {
+		RequestPredicate predicate1 = request -> true;
+		RequestPredicate predicate2 = request -> false;
+		RequestPredicate predicate3 = request -> false;
+
+		assertTrue(predicate1.or(predicate2).test(request));
+		assertTrue(predicate2.or(predicate1).test(request));
+		assertFalse(predicate2.or(predicate3).test(request));
+	}
+
+}

spring-webmvc/src/test/java/org/springframework/web/servlet/function/RequestPredicatesTests.java

@@ -0,0 +1,230 @@
+/*
+ * Copyright 2002-2019 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
+ *
+ *      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.web.servlet.function;
+
+import java.util.Collections;
+import java.util.function.Function;
+
+import org.junit.Test;
+
+import org.springframework.http.HttpMethod;
+import org.springframework.http.MediaType;
+import org.springframework.mock.web.test.MockHttpServletRequest;
+import org.springframework.web.util.pattern.PathPatternParser;
+
+import static java.util.Collections.emptyList;
+import static org.junit.Assert.*;
+import static org.springframework.http.MediaType.TEXT_XML_VALUE;
+
+/**
+ * @author Arjen Poutsma
+ */
+public class RequestPredicatesTests {
+
+	@Test
+	public void all() {
+		RequestPredicate predicate = RequestPredicates.all();
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest();
+		ServerRequest request = new DefaultServerRequest(servletRequest, emptyList());
+		assertTrue(predicate.test(request));
+	}
+
+
+	@Test
+	public void method() {
+		HttpMethod httpMethod = HttpMethod.GET;
+		RequestPredicate predicate = RequestPredicates.method(httpMethod);
+
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "http://example.com");
+		ServerRequest request = new DefaultServerRequest(servletRequest, emptyList());
+		assertTrue(predicate.test(request));
+
+		servletRequest.setMethod("POST");
+		assertFalse(predicate.test(request));
+	}
+
+	@Test
+	public void methods() {
+		RequestPredicate predicate = RequestPredicates.methods(HttpMethod.GET, HttpMethod.HEAD);
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "http://example.com");
+		ServerRequest request = new DefaultServerRequest(servletRequest, emptyList());
+		assertTrue(predicate.test(request));
+
+		servletRequest.setMethod("HEAD");
+		assertTrue(predicate.test(request));
+
+		servletRequest.setMethod("POST");
+		assertFalse(predicate.test(request));
+	}
+
+	@Test
+	public void allMethods() {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/path");
+		ServerRequest request = new DefaultServerRequest(servletRequest, emptyList());
+
+		RequestPredicate predicate = RequestPredicates.GET("/p*");
+		assertTrue(predicate.test(request));
+
+		predicate = RequestPredicates.HEAD("/p*");
+		servletRequest.setMethod("HEAD");
+		assertTrue(predicate.test(request));
+
+		predicate = RequestPredicates.POST("/p*");
+		servletRequest.setMethod("POST");
+		assertTrue(predicate.test(request));
+
+		predicate = RequestPredicates.PUT("/p*");
+		servletRequest.setMethod("PUT");
+		assertTrue(predicate.test(request));
+
+		predicate = RequestPredicates.PATCH("/p*");
+		servletRequest.setMethod("PATCH");
+		assertTrue(predicate.test(request));
+
+		predicate = RequestPredicates.DELETE("/p*");
+		servletRequest.setMethod("DELETE");
+		assertTrue(predicate.test(request));
+
+		predicate = RequestPredicates.OPTIONS("/p*");
+		servletRequest.setMethod("OPTIONS");
+		assertTrue(predicate.test(request));
+	}
+
+	@Test
+	public void path() {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/path");
+		ServerRequest request = new DefaultServerRequest(servletRequest, emptyList());
+		RequestPredicate predicate = RequestPredicates.path("/p*");
+		assertTrue(predicate.test(request));
+
+		servletRequest = new MockHttpServletRequest("GET", "/foo");
+		request = new DefaultServerRequest(servletRequest, emptyList());
+		assertFalse(predicate.test(request));
+	}
+
+	@Test
+	public void pathEncoded() {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/foo%20bar");
+		ServerRequest request = new DefaultServerRequest(servletRequest, emptyList());
+
+		RequestPredicate predicate = RequestPredicates.path("/foo bar");
+		assertTrue(predicate.test(request));
+
+		servletRequest = new MockHttpServletRequest();
+		request = new DefaultServerRequest(servletRequest, emptyList());
+		assertFalse(predicate.test(request));
+	}
+
+	@Test
+	public void pathPredicates() {
+		PathPatternParser parser = new PathPatternParser();
+		parser.setCaseSensitive(false);
+		Function<String, RequestPredicate> pathPredicates = RequestPredicates.pathPredicates(parser);
+
+		RequestPredicate predicate = pathPredicates.apply("/P*");
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/path");
+		ServerRequest request = new DefaultServerRequest(servletRequest, emptyList());
+		assertTrue(predicate.test(request));
+	}
+
+
+	@Test
+	public void headers() {
+		String name = "MyHeader";
+		String value = "MyValue";
+		RequestPredicate predicate =
+				RequestPredicates.headers(
+						headers -> headers.header(name).equals(Collections.singletonList(value)));
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/path");
+		servletRequest.addHeader(name, value);
+		ServerRequest request = new DefaultServerRequest(servletRequest, emptyList());
+		assertTrue(predicate.test(request));
+
+		servletRequest = new MockHttpServletRequest();
+		request = new DefaultServerRequest(servletRequest, emptyList());
+		assertFalse(predicate.test(request));
+	}
+
+	@Test
+	public void contentType() {
+		MediaType json = MediaType.APPLICATION_JSON;
+		RequestPredicate predicate = RequestPredicates.contentType(json);
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/path");
+		servletRequest.setContentType(json.toString());
+		ServerRequest request = new DefaultServerRequest(servletRequest, emptyList());
+
+		assertTrue(predicate.test(request));
+
+		servletRequest = new MockHttpServletRequest();
+		request = new DefaultServerRequest(servletRequest, emptyList());
+		assertFalse(predicate.test(request));
+	}
+
+	@Test
+	public void accept() {
+		MediaType json = MediaType.APPLICATION_JSON;
+		RequestPredicate predicate = RequestPredicates.accept(json);
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/path");
+		servletRequest.addHeader("Accept", json.toString());
+		ServerRequest request = new DefaultServerRequest(servletRequest, emptyList());
+		assertTrue(predicate.test(request));
+
+		servletRequest = new MockHttpServletRequest();
+		servletRequest.addHeader("Accept", TEXT_XML_VALUE);
+		request = new DefaultServerRequest(servletRequest, emptyList());
+		assertFalse(predicate.test(request));
+	}
+
+	@Test
+	public void pathExtension() {
+		RequestPredicate predicate = RequestPredicates.pathExtension("txt");
+
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/file.txt");
+		ServerRequest request = new DefaultServerRequest(servletRequest, emptyList());
+		assertTrue(predicate.test(request));
+
+		servletRequest = new MockHttpServletRequest("GET", "/FILE.TXT");
+		request = new DefaultServerRequest(servletRequest, emptyList());
+		assertTrue(predicate.test(request));
+
+		predicate = RequestPredicates.pathExtension("bar");
+		assertFalse(predicate.test(request));
+
+		servletRequest = new MockHttpServletRequest("GET", "/file.foo");
+		request = new DefaultServerRequest(servletRequest, emptyList());
+		assertFalse(predicate.test(request));
+	}
+
+	@Test
+	public void param() {
+		RequestPredicate predicate = RequestPredicates.param("foo", "bar");
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/path");
+		servletRequest.addParameter("foo", "bar");
+		ServerRequest request = new DefaultServerRequest(servletRequest, emptyList());
+		assertTrue(predicate.test(request));
+
+		predicate = RequestPredicates.param("foo", s -> s.equals("bar"));
+		assertTrue(predicate.test(request));
+
+		predicate = RequestPredicates.param("foo", "baz");
+		assertFalse(predicate.test(request));
+
+		predicate = RequestPredicates.param("foo", s -> s.equals("baz"));
+		assertFalse(predicate.test(request));
+	}
+
+}

spring-webmvc/src/test/java/org/springframework/web/servlet/function/ResourceHandlerFunctionTests.java

@@ -0,0 +1,136 @@
+/*
+ * Copyright 2002-2019 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
+ *
+ *      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.web.servlet.function;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.util.Collections;
+import java.util.EnumSet;
+import java.util.List;
+import javax.servlet.ServletException;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.core.io.Resource;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.http.converter.ResourceHttpMessageConverter;
+import org.springframework.mock.web.test.MockHttpServletRequest;
+import org.springframework.mock.web.test.MockHttpServletResponse;
+import org.springframework.web.servlet.ModelAndView;
+
+import static org.junit.Assert.*;
+
+/**
+ * @author Arjen Poutsma
+ */
+public class ResourceHandlerFunctionTests {
+
+	private final Resource resource = new ClassPathResource("response.txt", getClass());
+
+	private final ResourceHandlerFunction handlerFunction = new ResourceHandlerFunction(this.resource);
+
+	private ServerResponse.Context context;
+
+	private ResourceHttpMessageConverter messageConverter;
+
+	@Before
+	public void createContext() {
+		this.messageConverter = new ResourceHttpMessageConverter();
+		this.context = new ServerResponse.Context() {
+			@Override
+			public List<HttpMessageConverter<?>> messageConverters() {
+				return Collections.singletonList(messageConverter);
+			}
+
+		};
+	}
+
+
+	@Test
+	public void get() throws IOException, ServletException {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/");
+		ServerRequest request = new DefaultServerRequest(servletRequest, Collections.singletonList(messageConverter));
+
+		ServerResponse response = this.handlerFunction.handle(request);
+		assertEquals(HttpStatus.OK, response.statusCode());
+		assertTrue(response instanceof EntityResponse);
+		@SuppressWarnings("unchecked")
+		EntityResponse<Resource> entityResponse = (EntityResponse<Resource>) response;
+		assertEquals(this.resource, entityResponse.entity());
+
+		MockHttpServletResponse servletResponse = new MockHttpServletResponse();
+		ModelAndView mav = response.writeTo(servletRequest, servletResponse, this.context);
+		assertNull(mav);
+
+		assertEquals(200, servletResponse.getStatus());
+		byte[] expectedBytes = Files.readAllBytes(this.resource.getFile().toPath());
+		byte[] actualBytes = servletResponse.getContentAsByteArray();
+		assertArrayEquals(expectedBytes, actualBytes);
+		assertEquals(MediaType.TEXT_PLAIN_VALUE, servletResponse.getContentType());
+		assertEquals(this.resource.contentLength(),servletResponse.getContentLength());
+	}
+
+	@Test
+	public void head() throws IOException, ServletException {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("HEAD", "/");
+		ServerRequest request = new DefaultServerRequest(servletRequest, Collections.singletonList(messageConverter));
+
+		ServerResponse response = this.handlerFunction.handle(request);
+		assertEquals(HttpStatus.OK, response.statusCode());
+		assertTrue(response instanceof EntityResponse);
+		@SuppressWarnings("unchecked")
+		EntityResponse<Resource> entityResponse = (EntityResponse<Resource>) response;
+		assertEquals(this.resource.getFilename(), entityResponse.entity().getFilename());
+
+
+		MockHttpServletResponse servletResponse = new MockHttpServletResponse();
+		ModelAndView mav = response.writeTo(servletRequest, servletResponse, this.context);
+		assertNull(mav);
+
+		assertEquals(200, servletResponse.getStatus());
+		byte[] actualBytes = servletResponse.getContentAsByteArray();
+		assertEquals(0, actualBytes.length);
+		assertEquals(MediaType.TEXT_PLAIN_VALUE, servletResponse.getContentType());
+		assertEquals(this.resource.contentLength(),servletResponse.getContentLength());
+	}
+
+
+	@Test
+	public void options() throws ServletException, IOException {
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("OPTIONS", "/");
+		ServerRequest request = new DefaultServerRequest(servletRequest, Collections.singletonList(messageConverter));
+
+		ServerResponse response = this.handlerFunction.handle(request);
+		assertEquals(HttpStatus.OK, response.statusCode());
+		assertEquals(EnumSet.of(HttpMethod.GET, HttpMethod.HEAD, HttpMethod.OPTIONS), response.headers().getAllow());
+
+		MockHttpServletResponse servletResponse = new MockHttpServletResponse();
+		ModelAndView mav = response.writeTo(servletRequest, servletResponse, this.context);
+		assertNull(mav);
+
+		assertEquals(200, servletResponse.getStatus());
+		assertEquals("GET,HEAD,OPTIONS", servletResponse.getHeader("Allow"));
+		byte[] actualBytes = servletResponse.getContentAsByteArray();
+		assertEquals(0, actualBytes.length);
+	}
+
+}

spring-webmvc/src/test/java/org/springframework/web/servlet/function/RouterFunctionBuilderTests.java

@@ -0,0 +1,188 @@
+/*
+ * Copyright 2002-2019 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
+ *
+ *      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.web.servlet.function;
+
+import java.util.Optional;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import org.junit.Test;
+
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.core.io.Resource;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.mock.web.test.MockHttpServletRequest;
+
+import static java.util.Collections.emptyList;
+import static org.junit.Assert.*;
+
+/**
+ * @author Arjen Poutsma
+ */
+public class RouterFunctionBuilderTests {
+
+	@Test
+	public void route() {
+		RouterFunction<ServerResponse> route = RouterFunctions.route()
+				.GET("/foo", request -> ServerResponse.ok().build())
+				.POST("/", RequestPredicates.contentType(MediaType.TEXT_PLAIN),
+						request -> ServerResponse.noContent().build())
+				.build();
+
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/foo");
+		ServerRequest fooRequest = new DefaultServerRequest(servletRequest, emptyList());
+
+		Optional<Integer> responseStatus = route.route(fooRequest)
+				.map(handlerFunction -> handle(handlerFunction, fooRequest))
+				.map(ServerResponse::statusCode)
+				.map(HttpStatus::value);
+		assertEquals(200, responseStatus.get().intValue());
+
+		servletRequest = new MockHttpServletRequest("POST", "/");
+		servletRequest.setContentType("text/plain");
+		ServerRequest barRequest = new DefaultServerRequest(servletRequest, emptyList());
+
+		responseStatus = route.route(barRequest)
+				.map(handlerFunction -> handle(handlerFunction, barRequest))
+				.map(ServerResponse::statusCode)
+				.map(HttpStatus::value);
+		assertEquals(204, responseStatus.get().intValue());
+
+		servletRequest = new MockHttpServletRequest("POST", "/");
+		ServerRequest invalidRequest = new DefaultServerRequest(servletRequest, emptyList());
+
+		responseStatus = route.route(invalidRequest)
+				.map(handlerFunction -> handle(handlerFunction, invalidRequest))
+				.map(ServerResponse::statusCode)
+				.map(HttpStatus::value);
+
+		assertFalse(responseStatus.isPresent());
+
+	}
+
+	private static ServerResponse handle(HandlerFunction<ServerResponse> handlerFunction,
+			ServerRequest request) {
+		try {
+			return handlerFunction.handle(request);
+		}
+		catch (Exception e) {
+			fail(e.getMessage());
+			return null;
+		}
+	}
+
+	@Test
+	public void resources() {
+		Resource resource = new ClassPathResource("/org/springframework/web/servlet/function/");
+		assertTrue(resource.exists());
+
+		RouterFunction<ServerResponse> route = RouterFunctions.route()
+				.resources("/resources/**", resource)
+				.build();
+
+		MockHttpServletRequest servletRequest =
+				new MockHttpServletRequest("GET", "/resources/response.txt");
+		ServerRequest resourceRequest = new DefaultServerRequest(servletRequest, emptyList());
+
+		Optional<Integer> responseStatus = route.route(resourceRequest)
+				.map(handlerFunction -> handle(handlerFunction, resourceRequest))
+				.map(ServerResponse::statusCode)
+				.map(HttpStatus::value);
+		assertEquals(200, responseStatus.get().intValue());
+
+		servletRequest = new MockHttpServletRequest("POST", "/resources/foo.txt");
+		ServerRequest invalidRequest = new DefaultServerRequest(servletRequest, emptyList());
+
+		responseStatus = route.route(invalidRequest)
+				.map(handlerFunction -> handle(handlerFunction, invalidRequest))
+				.map(ServerResponse::statusCode)
+				.map(HttpStatus::value);
+		assertFalse(responseStatus.isPresent());
+	}
+
+	@Test
+	public void nest() {
+		RouterFunction<ServerResponse> route = RouterFunctions.route()
+				.path("/foo", builder ->
+						builder.path("/bar",
+								() -> RouterFunctions.route()
+										.GET("/baz", request -> ServerResponse.ok().build())
+										.build()))
+				.build();
+
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/foo/bar/baz");
+		ServerRequest fooRequest = new DefaultServerRequest(servletRequest, emptyList());
+
+		Optional<Integer> responseStatus = route.route(fooRequest)
+				.map(handlerFunction -> handle(handlerFunction, fooRequest))
+				.map(ServerResponse::statusCode)
+				.map(HttpStatus::value);
+		assertEquals(200, responseStatus.get().intValue());
+	}
+
+	@Test
+	public void filters() {
+		AtomicInteger filterCount = new AtomicInteger();
+
+		RouterFunction<ServerResponse> route = RouterFunctions.route()
+				.GET("/foo", request -> ServerResponse.ok().build())
+				.GET("/bar", request -> {
+					throw new IllegalStateException();
+				})
+				.before(request -> {
+					int count = filterCount.getAndIncrement();
+					assertEquals(0, count);
+					return request;
+				})
+				.after((request, response) -> {
+					int count = filterCount.getAndIncrement();
+					assertEquals(3, count);
+					return response;
+				})
+				.filter((request, next) -> {
+					int count = filterCount.getAndIncrement();
+					assertEquals(1, count);
+					ServerResponse responseMono = next.handle(request);
+					count = filterCount.getAndIncrement();
+					assertEquals(2, count);
+					return responseMono;
+				})
+				.onError(IllegalStateException.class,
+						(e, request) -> ServerResponse.status(HttpStatus.INTERNAL_SERVER_ERROR)
+								.build())
+				.build();
+
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest("GET", "/foo");
+		ServerRequest fooRequest = new DefaultServerRequest(servletRequest, emptyList());
+
+		Optional<ServerResponse> fooResponse = route.route(fooRequest)
+				.map(handlerFunction -> handle(handlerFunction, fooRequest));
+		assertEquals(4, filterCount.get());
+
+		filterCount.set(0);
+
+		servletRequest = new MockHttpServletRequest("GET", "/bar");
+		ServerRequest barRequest = new DefaultServerRequest(servletRequest, emptyList());
+
+		Optional<Integer> responseStatus = route.route(barRequest)
+				.map(handlerFunction -> handle(handlerFunction, barRequest))
+				.map(ServerResponse::statusCode)
+				.map(HttpStatus::value);
+		assertEquals(500, responseStatus.get().intValue());
+	}
+
+}

spring-webmvc/src/test/java/org/springframework/web/servlet/function/RouterFunctionTests.java

@@ -0,0 +1,125 @@
+/*
+ * Copyright 2002-2019 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
+ *
+ *      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.web.servlet.function;
+
+import java.util.Optional;
+
+import org.junit.Test;
+
+import org.springframework.mock.web.test.MockHttpServletRequest;
+
+import static java.util.Collections.emptyList;
+import static org.junit.Assert.*;
+
+/**
+ * @author Arjen Poutsma
+ */
+@SuppressWarnings("unchecked")
+public class RouterFunctionTests {
+
+	@Test
+	public void and() {
+		HandlerFunction<ServerResponse> handlerFunction = request -> ServerResponse.ok().build();
+		RouterFunction<ServerResponse> routerFunction1 = request -> Optional.empty();
+		RouterFunction<ServerResponse> routerFunction2 = request -> Optional.of(handlerFunction);
+
+		RouterFunction<ServerResponse> result = routerFunction1.and(routerFunction2);
+		assertNotNull(result);
+
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest();
+		ServerRequest request = new DefaultServerRequest(servletRequest, emptyList());
+
+		Optional<HandlerFunction<ServerResponse>> resultHandlerFunction = result.route(request);
+		assertTrue(resultHandlerFunction.isPresent());
+		assertEquals(handlerFunction, resultHandlerFunction.get());
+	}
+
+
+	@Test
+	public void andOther() {
+		HandlerFunction<ServerResponse> handlerFunction = request -> ServerResponse.ok().body("42");
+		RouterFunction<?> routerFunction1 = request -> Optional.empty();
+		RouterFunction<ServerResponse> routerFunction2 = request -> Optional.of(handlerFunction);
+
+		RouterFunction<?> result = routerFunction1.andOther(routerFunction2);
+		assertNotNull(result);
+
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest();
+		ServerRequest request = new DefaultServerRequest(servletRequest, emptyList());
+
+		Optional<? extends HandlerFunction<?>> resultHandlerFunction = result.route(request);
+		assertTrue(resultHandlerFunction.isPresent());
+		assertEquals(handlerFunction, resultHandlerFunction.get());
+	}
+
+
+	@Test
+	public void andRoute() {
+		RouterFunction<ServerResponse> routerFunction1 = request -> Optional.empty();
+		RequestPredicate requestPredicate = request -> true;
+
+		RouterFunction<ServerResponse> result = routerFunction1.andRoute(requestPredicate, this::handlerMethod);
+		assertNotNull(result);
+
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest();
+		ServerRequest request = new DefaultServerRequest(servletRequest, emptyList());
+
+		Optional<? extends HandlerFunction<?>> resultHandlerFunction = result.route(request);
+		assertTrue(resultHandlerFunction.isPresent());
+	}
+
+
+	@Test
+	public void filter() {
+		String string = "42";
+		HandlerFunction<EntityResponse<String>> handlerFunction =
+				request -> EntityResponse.fromObject(string).build();
+		RouterFunction<EntityResponse<String>> routerFunction =
+				request -> Optional.of(handlerFunction);
+
+		HandlerFilterFunction<EntityResponse<String>, EntityResponse<Integer>> filterFunction =
+				(request, next) -> {
+					String stringResponse = next.handle(request).entity();
+					Integer intResponse = Integer.parseInt(stringResponse);
+					return EntityResponse.fromObject(intResponse).build();
+				};
+
+		RouterFunction<EntityResponse<Integer>> result = routerFunction.filter(filterFunction);
+		assertNotNull(result);
+
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest();
+		ServerRequest request = new DefaultServerRequest(servletRequest, emptyList());
+
+		Optional<EntityResponse<Integer>> resultHandlerFunction = result.route(request)
+				.map(hf -> {
+					try {
+						return hf.handle(request);
+					}
+					catch (Exception e) {
+						fail(e.getMessage());
+						return null;
+					}
+				});
+		assertTrue(resultHandlerFunction.isPresent());
+		assertEquals(42, (int)resultHandlerFunction.get().entity());
+	}
+
+
+	private ServerResponse handlerMethod(ServerRequest request) {
+		return ServerResponse.ok().body("42");
+	}
+}

spring-webmvc/src/test/java/org/springframework/web/servlet/function/RouterFunctionsTests.java

@@ -0,0 +1,104 @@
+/*
+ * Copyright 2002-2019 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
+ *
+ *      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.web.servlet.function;
+
+import java.util.Collections;
+import java.util.Optional;
+
+import org.junit.Test;
+
+import org.springframework.mock.web.test.MockHttpServletRequest;
+
+import static org.junit.Assert.*;
+import static org.mockito.Mockito.*;
+
+/**
+ * @author Arjen Poutsma
+ */
+@SuppressWarnings("unchecked")
+public class RouterFunctionsTests {
+
+	@Test
+	public void routeMatch() {
+		HandlerFunction<ServerResponse> handlerFunction = request -> ServerResponse.ok().build();
+
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest();
+		ServerRequest request = new DefaultServerRequest(servletRequest, Collections.emptyList());
+		RequestPredicate requestPredicate = mock(RequestPredicate.class);
+		when(requestPredicate.test(request)).thenReturn(true);
+
+		RouterFunction<ServerResponse>
+				result = RouterFunctions.route(requestPredicate, handlerFunction);
+		assertNotNull(result);
+
+		Optional<HandlerFunction<ServerResponse>> resultHandlerFunction = result.route(request);
+		assertTrue(resultHandlerFunction.isPresent());
+		assertEquals(handlerFunction, resultHandlerFunction.get());
+	}
+
+	@Test
+	public void routeNoMatch() {
+		HandlerFunction<ServerResponse> handlerFunction = request -> ServerResponse.ok().build();
+
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest();
+		ServerRequest request = new DefaultServerRequest(servletRequest, Collections.emptyList());
+		RequestPredicate requestPredicate = mock(RequestPredicate.class);
+		when(requestPredicate.test(request)).thenReturn(false);
+
+		RouterFunction<ServerResponse> result = RouterFunctions.route(requestPredicate, handlerFunction);
+		assertNotNull(result);
+
+		Optional<HandlerFunction<ServerResponse>> resultHandlerFunction = result.route(request);
+		assertFalse(resultHandlerFunction.isPresent());
+	}
+
+	@Test
+	public void nestMatch() {
+		HandlerFunction<ServerResponse> handlerFunction = request -> ServerResponse.ok().build();
+		RouterFunction<ServerResponse> routerFunction = request -> Optional.of(handlerFunction);
+
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest();
+		ServerRequest request = new DefaultServerRequest(servletRequest, Collections.emptyList());
+		RequestPredicate requestPredicate = mock(RequestPredicate.class);
+		when(requestPredicate.nest(request)).thenReturn(Optional.of(request));
+
+		RouterFunction<ServerResponse> result = RouterFunctions.nest(requestPredicate, routerFunction);
+		assertNotNull(result);
+
+		Optional<HandlerFunction<ServerResponse>> resultHandlerFunction = result.route(request);
+		assertTrue(resultHandlerFunction.isPresent());
+		assertEquals(handlerFunction, resultHandlerFunction.get());
+	}
+
+	@Test
+	public void nestNoMatch() {
+		HandlerFunction<ServerResponse> handlerFunction = request -> ServerResponse.ok().build();
+		RouterFunction<ServerResponse> routerFunction = request -> Optional.of(handlerFunction);
+
+		MockHttpServletRequest servletRequest = new MockHttpServletRequest();
+		ServerRequest request = new DefaultServerRequest(servletRequest, Collections.emptyList());
+		RequestPredicate requestPredicate = mock(RequestPredicate.class);
+		when(requestPredicate.nest(request)).thenReturn(Optional.empty());
+
+		RouterFunction<ServerResponse> result = RouterFunctions.nest(requestPredicate, routerFunction);
+		assertNotNull(result);
+
+		Optional<HandlerFunction<ServerResponse>> resultHandlerFunction = result.route(request);
+		assertFalse(resultHandlerFunction.isPresent());
+	}
+
+}

spring-webmvc/src/test/java/org/springframework/web/servlet/function/ToStringVisitorTests.java

@@ -0,0 +1,113 @@
+/*
+ * Copyright 2002-2019 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
+ *
+ *      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.web.servlet.function;
+
+import org.junit.Test;
+
+import org.springframework.http.HttpMethod;
+import org.springframework.http.MediaType;
+
+import static org.junit.Assert.*;
+import static org.springframework.web.servlet.function.RequestPredicates.GET;
+import static org.springframework.web.servlet.function.RequestPredicates.accept;
+import static org.springframework.web.servlet.function.RequestPredicates.contentType;
+import static org.springframework.web.servlet.function.RequestPredicates.method;
+import static org.springframework.web.servlet.function.RequestPredicates.methods;
+import static org.springframework.web.servlet.function.RequestPredicates.param;
+import static org.springframework.web.servlet.function.RequestPredicates.path;
+import static org.springframework.web.servlet.function.RequestPredicates.pathExtension;
+import static org.springframework.web.servlet.function.RouterFunctions.route;
+
+/**
+ * @author Arjen Poutsma
+ */
+public class ToStringVisitorTests {
+
+	@Test
+	public void nested() {
+		HandlerFunction<ServerResponse> handler = new SimpleHandlerFunction();
+		RouterFunction<ServerResponse> routerFunction = route()
+				.path("/foo", builder -> {
+					builder.path("/bar", () -> route()
+							.GET("/baz", handler)
+							.build());
+				})
+				.build();
+
+		ToStringVisitor visitor = new ToStringVisitor();
+		routerFunction.accept(visitor);
+		String result = visitor.toString();
+
+		String expected = "/foo => {\n" +
+				" /bar => {\n" +
+				"  (GET && /baz) -> \n" +
+				" }\n" +
+				"}";
+		assertEquals(expected, result);
+	}
+
+	@Test
+	public void predicates() {
+		testPredicate(methods(HttpMethod.GET), "GET");
+		testPredicate(methods(HttpMethod.GET, HttpMethod.POST), "[GET, POST]");
+
+		testPredicate(path("/foo"), "/foo");
+
+		testPredicate(pathExtension("foo"), "*.foo");
+
+		testPredicate(contentType(MediaType.APPLICATION_JSON), "Content-Type: application/json");
+		testPredicate(contentType(MediaType.APPLICATION_JSON, MediaType.TEXT_PLAIN), "Content-Type: [application/json, text/plain]");
+
+		testPredicate(accept(MediaType.APPLICATION_JSON), "Accept: application/json");
+
+		testPredicate(param("foo", "bar"), "?foo == bar");
+
+		testPredicate(method(HttpMethod.GET).and(path("/foo")), "(GET && /foo)");
+
+		testPredicate(method(HttpMethod.GET).or(path("/foo")), "(GET || /foo)");
+
+		testPredicate(method(HttpMethod.GET).negate(), "!(GET)");
+
+		testPredicate(GET("/foo")
+				.or(contentType(MediaType.TEXT_PLAIN))
+				.and(accept(MediaType.APPLICATION_JSON).negate()),
+				"(((GET && /foo) || Content-Type: text/plain) && !(Accept: application/json))");
+	}
+
+	private void testPredicate(RequestPredicate predicate, String expected) {
+		ToStringVisitor visitor = new ToStringVisitor();
+		predicate.accept(visitor);
+		String result = visitor.toString();
+
+		assertEquals(expected, result);
+	}
+
+
+	private static class SimpleHandlerFunction implements HandlerFunction<ServerResponse> {
+
+		@Override
+		public ServerResponse handle(ServerRequest request) {
+			return ServerResponse.ok().build();
+		}
+
+		@Override
+		public String toString() {
+			return "";
+		}
+	}
+
+}

spring-webmvc/src/test/resources/org/springframework/web/servlet/function/child/response.txt

@@ -0,0 +1,2 @@
+Hello World
+This is a sample response text file.

spring-webmvc/src/test/resources/org/springframework/web/servlet/function/response.txt

@@ -0,0 +1,2 @@
+Hello World
+This is a sample response text file.