Add RestTestClient

Fixes spring-projectsgh-31275

Author: rworsnop

spring-test/src/main/java/org/springframework/test/web/client/MockMvcClientHttpRequestFactory.java

@@ -20,6 +20,9 @@
 import java.nio.charset.StandardCharsets;
 import java.util.List;
 
+import jakarta.servlet.http.Cookie;
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpMethod;
 import org.springframework.http.HttpStatus;
@@ -31,6 +34,7 @@
 import org.springframework.mock.http.client.MockClientHttpResponse;
 import org.springframework.mock.web.MockHttpServletResponse;
 import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.request.MockHttpServletRequestBuilder;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
 
@@ -67,8 +71,14 @@ private ClientHttpResponse getClientHttpResponse(
 			HttpMethod httpMethod, URI uri, HttpHeaders requestHeaders, byte[] requestBody) {
 
 		try {
+			Cookie[] cookies = parseCookies(requestHeaders.get(HttpHeaders.COOKIE));
+			MockHttpServletRequestBuilder requestBuilder = request(httpMethod, uri)
+					.content(requestBody).headers(requestHeaders);
+			if (cookies.length > 0) {
+				requestBuilder.cookie(cookies);
+			}
 			MockHttpServletResponse servletResponse = this.mockMvc
-					.perform(request(httpMethod, uri).content(requestBody).headers(requestHeaders))
+					.perform(requestBuilder)
 					.andReturn()
 					.getResponse();
 
@@ -92,6 +102,22 @@ private ClientHttpResponse getClientHttpResponse(
 		}
 	}
 
+	private static Cookie[] parseCookies(@Nullable List<String> headerValues) {
+		if (headerValues == null) {
+			return new Cookie[0];
+		}
+		return headerValues.stream()
+				.flatMap(header -> StringUtils.commaDelimitedListToSet(header).stream())
+				.map(MockMvcClientHttpRequestFactory::parseCookie)
+				.toArray(Cookie[]::new);
+	}
+
+	private static Cookie parseCookie(String cookie) {
+		String[] parts = StringUtils.split(cookie, "=");
+		Assert.isTrue(parts != null && parts.length == 2, "Invalid cookie: '" + cookie + "'");
+		return new Cookie(parts[0], parts[1]);
+	}
+
 	private HttpHeaders getResponseHeaders(MockHttpServletResponse response) {
 		HttpHeaders headers = new HttpHeaders();
 		for (String name : response.getHeaderNames()) {

spring-test/src/main/java/org/springframework/test/web/server/AbstractMockMvcServerSpec.java

@@ -0,0 +1,105 @@
+/*
+ * Copyright 2002-2025 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.test.web.server;
+
+import jakarta.servlet.Filter;
+
+import org.springframework.http.client.ClientHttpRequestFactory;
+import org.springframework.test.web.client.MockMvcClientHttpRequestFactory;
+import org.springframework.test.web.servlet.DispatcherServletCustomizer;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.RequestBuilder;
+import org.springframework.test.web.servlet.ResultMatcher;
+import org.springframework.test.web.servlet.setup.ConfigurableMockMvcBuilder;
+import org.springframework.test.web.servlet.setup.MockMvcConfigurer;
+
+/**
+ * Base class for implementations of {@link RestTestClient.MockMvcServerSpec}
+ * that simply delegates to a {@link org.springframework.test.web.servlet.setup.ConfigurableMockMvcBuilder} supplied by
+ * the concrete subclasses.
+ *
+ * @author Rob Worsnop
+ * @param <B> the type of the concrete subclass spec
+ */
+abstract class AbstractMockMvcServerSpec<B extends RestTestClient.MockMvcServerSpec<B>>
+		implements RestTestClient.MockMvcServerSpec<B> {
+
+	@Override
+	public <T extends B> T filters(Filter... filters) {
+		getMockMvcBuilder().addFilters(filters);
+		return self();
+	}
+
+	@Override
+	public final <T extends B> T filter(Filter filter, String... urlPatterns) {
+		getMockMvcBuilder().addFilter(filter, urlPatterns);
+		return self();
+	}
+
+	@Override
+	public <T extends B> T defaultRequest(RequestBuilder requestBuilder) {
+		getMockMvcBuilder().defaultRequest(requestBuilder);
+		return self();
+	}
+
+	@Override
+	public <T extends B> T alwaysExpect(ResultMatcher resultMatcher) {
+		getMockMvcBuilder().alwaysExpect(resultMatcher);
+		return self();
+	}
+
+	@Override
+	public <T extends B> T dispatchOptions(boolean dispatchOptions) {
+		getMockMvcBuilder().dispatchOptions(dispatchOptions);
+		return self();
+	}
+
+	@Override
+	public <T extends B> T dispatcherServletCustomizer(DispatcherServletCustomizer customizer) {
+		getMockMvcBuilder().addDispatcherServletCustomizer(customizer);
+		return self();
+	}
+
+	@Override
+	public <T extends B> T apply(MockMvcConfigurer configurer) {
+		getMockMvcBuilder().apply(configurer);
+		return self();
+	}
+
+	@SuppressWarnings("unchecked")
+	private <T extends B> T self() {
+		return (T) this;
+	}
+
+	/**
+	 * Return the concrete {@link ConfigurableMockMvcBuilder} to delegate
+	 * configuration methods and to use to create the {@link MockMvc}.
+	 */
+	protected abstract ConfigurableMockMvcBuilder<?> getMockMvcBuilder();
+
+	@Override
+	public RestTestClient.Builder configureClient() {
+		MockMvc mockMvc = getMockMvcBuilder().build();
+		ClientHttpRequestFactory requestFactory = new MockMvcClientHttpRequestFactory(mockMvc);
+		return RestTestClient.bindToServer(requestFactory);
+	}
+
+	@Override
+	public RestTestClient build() {
+		return configureClient().build();
+	}
+}

spring-test/src/main/java/org/springframework/test/web/server/ApplicationContextMockMvcSpec.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2002-2025 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.test.web.server;
+
+import org.springframework.test.web.servlet.setup.ConfigurableMockMvcBuilder;
+import org.springframework.test.web.servlet.setup.DefaultMockMvcBuilder;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+import org.springframework.web.context.WebApplicationContext;
+
+/**
+ * Simple wrapper around a {@link DefaultMockMvcBuilder}.
+ *
+ * @author Rob Worsnop
+ */
+class ApplicationContextMockMvcSpec extends AbstractMockMvcServerSpec<ApplicationContextMockMvcSpec> {
+	private final DefaultMockMvcBuilder mockMvcBuilder;
+
+	public ApplicationContextMockMvcSpec(WebApplicationContext context) {
+		this.mockMvcBuilder = MockMvcBuilders.webAppContextSetup(context);
+	}
+
+	@Override
+	protected ConfigurableMockMvcBuilder<?> getMockMvcBuilder() {
+		return this.mockMvcBuilder;
+	}
+}