Use RestClient in tests and infrastructure code

Closes gh-51120

integration-test/spring-boot-server-integration-tests/src/intTest/java/org/springframework/boot/context/embedded/EmbeddedServerContainerInvocationContextProvider.java

@@ -19,7 +19,6 @@ package org.springframework.boot.context.embedded;
 import java.io.File;
 import java.io.IOException;
 import java.lang.reflect.Constructor;
-import java.net.URI;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.Arrays;
@@ -49,9 +48,10 @@ import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
 import org.springframework.util.FileSystemUtils;
 import org.springframework.util.ReflectionUtils;
 import org.springframework.util.StringUtils;
-import org.springframework.web.client.NoOpResponseErrorHandler;
-import org.springframework.web.client.RestTemplate;
-import org.springframework.web.util.UriTemplateHandler;
+import org.springframework.web.client.RestClient;
+import org.springframework.web.client.RestClient.ResponseSpec.ErrorHandler;
+import org.springframework.web.util.DefaultUriBuilderFactory;
+import org.springframework.web.util.DefaultUriBuilderFactory.EncodingMode;
 
 /**
  * {@link TestTemplateInvocationContextProvider} for templated
@@ -152,7 +152,7 @@ class EmbeddedServerContainerInvocationContextProvider
 
 		@Override
 		public List<Extension> getAdditionalExtensions() {
-			return Arrays.asList(this.launcher, new RestTemplateParameterResolver(this.launcher));
+			return Arrays.asList(this.launcher, new RestClientParameterResolver(this.launcher));
 		}
 
 		@Override
@@ -165,7 +165,7 @@ class EmbeddedServerContainerInvocationContextProvider
 			if (parameterContext.getParameter().getType().equals(AbstractApplicationLauncher.class)) {
 				return true;
 			}
-			return parameterContext.getParameter().getType().equals(RestTemplate.class);
+			return parameterContext.getParameter().getType().equals(RestClient.class);
 		}
 
 		@Override
@@ -178,41 +178,35 @@ class EmbeddedServerContainerInvocationContextProvider
 
 	}
 
-	private static final class RestTemplateParameterResolver implements ParameterResolver {
+	private static final class RestClientParameterResolver implements ParameterResolver {
+
+		private static final ErrorHandler NOOP_ERROR_HANDLER = (request, response) -> {
+		};
 
 		private final AbstractApplicationLauncher launcher;
 
-		private RestTemplateParameterResolver(AbstractApplicationLauncher launcher) {
+		private RestClientParameterResolver(AbstractApplicationLauncher launcher) {
 			this.launcher = launcher;
 		}
 
 		@Override
 		public boolean supportsParameter(ParameterContext parameterContext, ExtensionContext extensionContext) {
-			return parameterContext.getParameter().getType().equals(RestTemplate.class);
+			return parameterContext.getParameter().getType().equals(RestClient.class);
 		}
 
 		@Override
 		public Object resolveParameter(ParameterContext parameterContext, ExtensionContext extensionContext) {
-			RestTemplate rest = new RestTemplate(new HttpComponentsClientHttpRequestFactory(HttpClients.custom()
-				.setRetryStrategy(new DefaultHttpRequestRetryStrategy(10, TimeValue.of(1, TimeUnit.SECONDS)))
-				.build()));
-			rest.setErrorHandler(new NoOpResponseErrorHandler());
-			rest.setUriTemplateHandler(new UriTemplateHandler() {
-
-				@Override
-				public URI expand(String uriTemplate, Object... uriVariables) {
-					return URI.create("http://localhost:" + RestTemplateParameterResolver.this.launcher.getHttpPort()
-							+ uriTemplate);
-				}
-
-				@Override
-				public URI expand(String uriTemplate, Map<String, ?> uriVariables) {
-					return URI.create("http://localhost:" + RestTemplateParameterResolver.this.launcher.getHttpPort()
-							+ uriTemplate);
-				}
-
-			});
-			return rest;
+			DefaultUriBuilderFactory uriBuilderFactory = new DefaultUriBuilderFactory(
+					"http://localhost:" + this.launcher.getHttpPort());
+			// Do not double encode test paths
+			uriBuilderFactory.setEncodingMode(EncodingMode.NONE);
+			return RestClient.builder()
+				.uriBuilderFactory(uriBuilderFactory)
+				.requestFactory(new HttpComponentsClientHttpRequestFactory(HttpClients.custom()
+					.setRetryStrategy(new DefaultHttpRequestRetryStrategy(10, TimeValue.of(1, TimeUnit.SECONDS)))
+					.build()))
+				.defaultStatusHandler((status) -> true, NOOP_ERROR_HANDLER)
+				.build();
 		}
 
 	}

integration-test/spring-boot-server-integration-tests/src/intTest/java/org/springframework/boot/context/embedded/EmbeddedServletContainerJarDevelopmentIntegrationTests.java

@@ -22,7 +22,7 @@ import org.junit.jupiter.api.condition.OS;
 
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -37,25 +37,31 @@ import static org.assertj.core.api.Assertions.assertThat;
 class EmbeddedServletContainerJarDevelopmentIntegrationTests {
 
 	@TestTemplate
-	void metaInfResourceFromDependencyIsAvailableViaHttp(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/nested-meta-inf-resource.txt", String.class);
+	void metaInfResourceFromDependencyIsAvailableViaHttp(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/nested-meta-inf-resource.txt")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}
 
 	@TestTemplate
 	@DisabledOnOs(OS.WINDOWS)
-	void metaInfResourceFromDependencyWithNameThatContainsReservedCharactersIsAvailableViaHttp(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity(
-				"/nested-reserved-%21%23%24%25%26%28%29%2A%2B%2C%3A%3D%3F%40%5B%5D-meta-inf-resource.txt",
-				String.class);
+	void metaInfResourceFromDependencyWithNameThatContainsReservedCharactersIsAvailableViaHttp(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/nested-reserved-%21%23%24%25%26%28%29%2A%2B%2C%3A%3D%3F%40%5B%5D-meta-inf-resource.txt")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(entity.getBody()).isEqualTo("encoded-name");
 	}
 
 	@TestTemplate
-	void metaInfResourceFromDependencyIsAvailableViaServletContext(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/servletContext?/nested-meta-inf-resource.txt",
-				String.class);
+	void metaInfResourceFromDependencyIsAvailableViaServletContext(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/servletContext?/nested-meta-inf-resource.txt")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}
 

integration-test/spring-boot-server-integration-tests/src/intTest/java/org/springframework/boot/context/embedded/EmbeddedServletContainerJarPackagingIntegrationTests.java

@@ -22,7 +22,7 @@ import org.junit.jupiter.api.condition.OS;
 
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -37,51 +37,64 @@ import static org.assertj.core.api.Assertions.assertThat;
 class EmbeddedServletContainerJarPackagingIntegrationTests {
 
 	@TestTemplate
-	void nestedMetaInfResourceIsAvailableViaHttp(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/nested-meta-inf-resource.txt", String.class);
+	void nestedMetaInfResourceIsAvailableViaHttp(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/nested-meta-inf-resource.txt")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}
 
 	@TestTemplate
 	@DisabledOnOs(OS.WINDOWS)
-	void nestedMetaInfResourceWithNameThatContainsReservedCharactersIsAvailableViaHttp(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity(
-				"/nested-reserved-%21%23%24%25%26%28%29%2A%2B%2C%3A%3D%3F%40%5B%5D-meta-inf-resource.txt",
-				String.class);
+	void nestedMetaInfResourceWithNameThatContainsReservedCharactersIsAvailableViaHttp(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/nested-reserved-%21%23%24%25%26%28%29%2A%2B%2C%3A%3D%3F%40%5B%5D-meta-inf-resource.txt")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(entity.getBody()).isEqualTo("encoded-name");
 	}
 
 	@TestTemplate
-	void nestedMetaInfResourceIsAvailableViaServletContext(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/servletContext?/nested-meta-inf-resource.txt",
-				String.class);
+	void nestedMetaInfResourceIsAvailableViaServletContext(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/servletContext?/nested-meta-inf-resource.txt")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}
 
 	@TestTemplate
-	void nestedJarIsNotAvailableViaHttp(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/BOOT-INF/lib/resources-1.0.jar", String.class);
+	void nestedJarIsNotAvailableViaHttp(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/BOOT-INF/lib/resources-1.0.jar")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.NOT_FOUND);
 	}
 
 	@TestTemplate
-	void applicationClassesAreNotAvailableViaHttp(RestTemplate rest) {
-		ResponseEntity<String> entity = rest
-			.getForEntity("/BOOT-INF/classes/com/example/ResourceHandlingApplication.class", String.class);
+	void applicationClassesAreNotAvailableViaHttp(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/BOOT-INF/classes/com/example/ResourceHandlingApplication.class")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.NOT_FOUND);
 	}
 
 	@TestTemplate
-	void launcherIsNotAvailableViaHttp(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/org/springframework/boot/loader/Launcher.class",
-				String.class);
+	void launcherIsNotAvailableViaHttp(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/org/springframework/boot/loader/Launcher.class")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.NOT_FOUND);
 	}
 
 	@TestTemplate
-	void conditionalOnWarDeploymentBeanIsNotAvailableForEmbeddedServer(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/war", String.class);
+	void conditionalOnWarDeploymentBeanIsNotAvailableForEmbeddedServer(RestClient rest) {
+		ResponseEntity<String> entity = rest.get().uri("/war").retrieve().toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.NOT_FOUND);
 	}
 

integration-test/spring-boot-server-integration-tests/src/intTest/java/org/springframework/boot/context/embedded/EmbeddedServletContainerWarDevelopmentIntegrationTests.java

@@ -28,7 +28,7 @@ import org.junit.jupiter.api.condition.OS;
 
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -43,37 +43,43 @@ import static org.assertj.core.api.Assertions.assertThat;
 class EmbeddedServletContainerWarDevelopmentIntegrationTests {
 
 	@TestTemplate
-	void metaInfResourceFromDependencyIsAvailableViaHttp(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/nested-meta-inf-resource.txt", String.class);
+	void metaInfResourceFromDependencyIsAvailableViaHttp(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/nested-meta-inf-resource.txt")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}
 
 	@TestTemplate
 	@DisabledOnOs(OS.WINDOWS)
-	void metaInfResourceFromDependencyWithNameThatContainsReservedCharactersIsAvailableViaHttp(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity(
-				"/nested-reserved-%21%23%24%25%26%28%29%2A%2B%2C%3A%3D%3F%40%5B%5D-meta-inf-resource.txt",
-				String.class);
+	void metaInfResourceFromDependencyWithNameThatContainsReservedCharactersIsAvailableViaHttp(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/nested-reserved-%21%23%24%25%26%28%29%2A%2B%2C%3A%3D%3F%40%5B%5D-meta-inf-resource.txt")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(entity.getBody()).isEqualTo("encoded-name");
 	}
 
 	@TestTemplate
-	void metaInfResourceFromDependencyIsAvailableViaServletContext(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/servletContext?/nested-meta-inf-resource.txt",
-				String.class);
+	void metaInfResourceFromDependencyIsAvailableViaServletContext(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/servletContext?/nested-meta-inf-resource.txt")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}
 
 	@TestTemplate
-	void webappResourcesAreAvailableViaHttp(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/webapp-resource.txt", String.class);
+	void webappResourcesAreAvailableViaHttp(RestClient rest) {
+		ResponseEntity<String> entity = rest.get().uri("/webapp-resource.txt").retrieve().toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}
 
 	@TestTemplate
-	void loaderClassesAreNotAvailableViaResourcePaths(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/resourcePaths", String.class);
+	void loaderClassesAreNotAvailableViaResourcePaths(RestClient rest) {
+		ResponseEntity<String> entity = rest.get().uri("/resourcePaths").retrieve().toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(readLines(entity.getBody()))
 			.noneMatch((resourcePath) -> resourcePath.startsWith("/org/springframework/boot/loader"));

integration-test/spring-boot-server-integration-tests/src/intTest/java/org/springframework/boot/context/embedded/EmbeddedServletContainerWarPackagingIntegrationTests.java

@@ -28,7 +28,7 @@ import org.junit.jupiter.api.condition.OS;
 
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -43,68 +43,85 @@ import static org.assertj.core.api.Assertions.assertThat;
 class EmbeddedServletContainerWarPackagingIntegrationTests {
 
 	@TestTemplate
-	void nestedMetaInfResourceIsAvailableViaHttp(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/nested-meta-inf-resource.txt", String.class);
+	void nestedMetaInfResourceIsAvailableViaHttp(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/nested-meta-inf-resource.txt")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}
 
 	@TestTemplate
 	@DisabledOnOs(OS.WINDOWS)
-	void nestedMetaInfResourceWithNameThatContainsReservedCharactersIsAvailableViaHttp(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity(
-				"/nested-reserved-%21%23%24%25%26%28%29%2A%2B%2C%3A%3D%3F%40%5B%5D-meta-inf-resource.txt",
-				String.class);
+	void nestedMetaInfResourceWithNameThatContainsReservedCharactersIsAvailableViaHttp(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/nested-reserved-%21%23%24%25%26%28%29%2A%2B%2C%3A%3D%3F%40%5B%5D-meta-inf-resource.txt")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(entity.getBody()).isEqualTo("encoded-name");
 	}
 
 	@TestTemplate
-	void nestedMetaInfResourceIsAvailableViaServletContext(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/servletContext?/nested-meta-inf-resource.txt",
-				String.class);
+	void nestedMetaInfResourceIsAvailableViaServletContext(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/servletContext?/nested-meta-inf-resource.txt")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}
 
 	@TestTemplate
-	void nestedJarIsNotAvailableViaHttp(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/WEB-INF/lib/resources-1.0.jar", String.class);
+	void nestedJarIsNotAvailableViaHttp(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/WEB-INF/lib/resources-1.0.jar")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.NOT_FOUND);
 	}
 
 	@TestTemplate
-	void applicationClassesAreNotAvailableViaHttp(RestTemplate rest) {
-		ResponseEntity<String> entity = rest
-			.getForEntity("/WEB-INF/classes/com/example/ResourceHandlingApplication.class", String.class);
+	void applicationClassesAreNotAvailableViaHttp(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/WEB-INF/classes/com/example/ResourceHandlingApplication.class")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.NOT_FOUND);
 	}
 
 	@TestTemplate
-	void webappResourcesAreAvailableViaHttp(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/webapp-resource.txt", String.class);
+	void webappResourcesAreAvailableViaHttp(RestClient rest) {
+		ResponseEntity<String> entity = rest.get().uri("/webapp-resource.txt").retrieve().toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}
 
 	@TestTemplate
-	void loaderClassesAreNotAvailableViaHttp(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/org/springframework/boot/loader/Launcher.class",
-				String.class);
+	void loaderClassesAreNotAvailableViaHttp(RestClient rest) {
+		ResponseEntity<String> entity = rest.get()
+			.uri("/org/springframework/boot/loader/Launcher.class")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.NOT_FOUND);
-		entity = rest.getForEntity("/org/springframework/../springframework/boot/loader/Launcher.class", String.class);
+		entity = rest.get()
+			.uri("/org/springframework/../springframework/boot/loader/Launcher.class")
+			.retrieve()
+			.toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.NOT_FOUND);
 	}
 
 	@TestTemplate
-	void loaderClassesAreNotAvailableViaResourcePaths(RestTemplate rest) {
-		ResponseEntity<String> entity = rest.getForEntity("/resourcePaths", String.class);
+	void loaderClassesAreNotAvailableViaResourcePaths(RestClient rest) {
+		ResponseEntity<String> entity = rest.get().uri("/resourcePaths").retrieve().toEntity(String.class);
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(readLines(entity.getBody()))
 			.noneMatch((resourcePath) -> resourcePath.startsWith("/org/springframework/boot/loader"));
 	}
 
 	@TestTemplate
-	void conditionalOnWarDeploymentBeanIsNotAvailableForEmbeddedServer(RestTemplate rest) {
-		assertThat(rest.getForEntity("/always", String.class).getStatusCode()).isEqualTo(HttpStatus.OK);
-		assertThat(rest.getForEntity("/conditionalOnWar", String.class).getStatusCode())
+	void conditionalOnWarDeploymentBeanIsNotAvailableForEmbeddedServer(RestClient rest) {
+		assertThat(rest.get().uri("/always").retrieve().toEntity(String.class).getStatusCode())
+			.isEqualTo(HttpStatus.OK);
+		assertThat(rest.get().uri("/conditionalOnWar").retrieve().toEntity(String.class).getStatusCode())
 			.isEqualTo(HttpStatus.NOT_FOUND);
 	}