Allow custom TestRestTemplate beans

Update `@SpringBootTest` `TestRestTemplate` support so that the bean
definition is only registered when the user has not defined or
auto-configured their own.

See gh-10556

spring-boot-project/spring-boot-test/src/main/java/org/springframework/boot/test/web/client/TestRestTemplate.java

 /*
- * Copyright 2012-2017 the original author or authors.
+ * Copyright 2012-2018 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.
@@ -65,7 +65,7 @@ import org.springframework.web.util.UriTemplateHandler;
  * Apache Http Client 4.3.2 or better is available (recommended) it will be used as the
  * client, and by default configured to ignore cookies and redirects.
  * <p>
- * Note: To prevent injection problems this class internally does not extend
+ * Note: To prevent injection problems this class intentionally does not extend
  * {@link RestTemplate}. If you need access to the underlying {@link RestTemplate} use
  * {@link #getRestTemplate()}.
  * <p>

spring-boot-project/spring-boot-test/src/main/java/org/springframework/boot/test/context/SpringBootTestContextCustomizer.java → spring-boot-project/spring-boot-test/src/main/java/org/springframework/boot/test/web/client/TestRestTemplateTestContextCustomizer.java

 /*
- * Copyright 2012-2017 the original author or authors.
+ * Copyright 2012-2018 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.
@@ -14,22 +14,29 @@
  * limitations under the License.
  */
 
-package org.springframework.boot.test.context;
+package org.springframework.boot.test.web.client;
 
 import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.BeanFactory;
+import org.springframework.beans.factory.BeanFactoryAware;
+import org.springframework.beans.factory.BeanFactoryUtils;
 import org.springframework.beans.factory.FactoryBean;
+import org.springframework.beans.factory.ListableBeanFactory;
 import org.springframework.beans.factory.NoSuchBeanDefinitionException;
+import org.springframework.beans.factory.config.BeanDefinition;
 import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
 import org.springframework.beans.factory.support.BeanDefinitionRegistry;
+import org.springframework.beans.factory.support.BeanDefinitionRegistryPostProcessor;
 import org.springframework.beans.factory.support.RootBeanDefinition;
-import org.springframework.boot.test.web.client.LocalHostUriTemplateHandler;
-import org.springframework.boot.test.web.client.TestRestTemplate;
+import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.web.client.TestRestTemplate.HttpClientOption;
 import org.springframework.boot.web.client.RestTemplateBuilder;
 import org.springframework.boot.web.servlet.server.AbstractServletWebServerFactory;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationContextAware;
 import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.context.annotation.ConfigurationClassPostProcessor;
+import org.springframework.core.Ordered;
 import org.springframework.core.annotation.AnnotatedElementUtils;
 import org.springframework.test.context.ContextCustomizer;
 import org.springframework.test.context.MergedContextConfiguration;
@@ -40,7 +47,7 @@ import org.springframework.test.context.MergedContextConfiguration;
  * @author Phillip Webb
  * @author Andy Wilkinson
  */
-class SpringBootTestContextCustomizer implements ContextCustomizer {
+class TestRestTemplateTestContextCustomizer implements ContextCustomizer {
 
 	@Override
 	public void customizeContext(ConfigurableApplicationContext context,
@@ -61,8 +68,11 @@ class SpringBootTestContextCustomizer implements ContextCustomizer {
 
 	private void registerTestRestTemplate(ConfigurableApplicationContext context,
 			BeanDefinitionRegistry registry) {
-		registry.registerBeanDefinition(TestRestTemplate.class.getName(),
-				new RootBeanDefinition(TestRestTemplateFactory.class));
+		RootBeanDefinition definition = new RootBeanDefinition(
+				TestRestTemplateRegistrar.class);
+		definition.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
+		registry.registerBeanDefinition(TestRestTemplateRegistrar.class.getName(),
+				definition);
 	}
 
 	@Override
@@ -78,6 +88,45 @@ class SpringBootTestContextCustomizer implements ContextCustomizer {
 		return true;
 	}
 
+	/**
+	 * {@link BeanDefinitionRegistryPostProcessor} that runs after the
+	 * {@link ConfigurationClassPostProcessor} and add a {@link TestRestTemplateFactory}
+	 * bean definition when a {@link TestRestTemplate} hasn't already been registered.
+	 */
+	private static class TestRestTemplateRegistrar
+			implements BeanDefinitionRegistryPostProcessor, Ordered, BeanFactoryAware {
+
+		private BeanFactory beanFactory;
+
+		@Override
+		public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
+			this.beanFactory = beanFactory;
+		}
+
+		@Override
+		public int getOrder() {
+			return Ordered.LOWEST_PRECEDENCE;
+		}
+
+		@Override
+		public void postProcessBeanDefinitionRegistry(BeanDefinitionRegistry registry)
+				throws BeansException {
+			if (BeanFactoryUtils.beanNamesForTypeIncludingAncestors(
+					(ListableBeanFactory) this.beanFactory,
+					TestRestTemplate.class).length == 0) {
+				registry.registerBeanDefinition(TestRestTemplate.class.getName(),
+						new RootBeanDefinition(TestRestTemplateFactory.class));
+			}
+
+		}
+
+		@Override
+		public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory)
+				throws BeansException {
+		}
+
+	}
+
 	/**
 	 * {@link FactoryBean} used to create and configure a {@link TestRestTemplate}.
 	 */
@@ -88,7 +137,7 @@ class SpringBootTestContextCustomizer implements ContextCustomizer {
 
 		private static final HttpClientOption[] SSL_OPTIONS = { HttpClientOption.SSL };
 
-		private TestRestTemplate object;
+		private TestRestTemplate template;
 
 		@Override
 		public void setApplicationContext(ApplicationContext applicationContext)
@@ -100,7 +149,7 @@ class SpringBootTestContextCustomizer implements ContextCustomizer {
 			LocalHostUriTemplateHandler handler = new LocalHostUriTemplateHandler(
 					applicationContext.getEnvironment(), sslEnabled ? "https" : "http");
 			template.setUriTemplateHandler(handler);
-			this.object = template;
+			this.template = template;
 		}
 
 		private boolean isSslEnabled(ApplicationContext context) {
@@ -137,7 +186,7 @@ class SpringBootTestContextCustomizer implements ContextCustomizer {
 
 		@Override
 		public TestRestTemplate getObject() throws Exception {
-			return this.object;
+			return this.template;
 		}
 
 	}

spring-boot-project/spring-boot-test/src/main/java/org/springframework/boot/test/context/SpringBootTestContextCustomizerFactory.java → spring-boot-project/spring-boot-test/src/main/java/org/springframework/boot/test/web/client/TestRestTemplateTestContextCustomizerFactory.java

 /*
- * Copyright 2012-2017 the original author or authors.
+ * Copyright 2012-2018 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.
@@ -14,10 +14,11 @@
  * limitations under the License.
  */
 
-package org.springframework.boot.test.context;
+package org.springframework.boot.test.web.client;
 
 import java.util.List;
 
+import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.core.annotation.AnnotatedElementUtils;
 import org.springframework.test.context.ContextConfigurationAttributes;
 import org.springframework.test.context.ContextCustomizer;
@@ -27,16 +28,16 @@ import org.springframework.test.context.ContextCustomizerFactory;
  * {@link ContextCustomizerFactory} for {@link SpringBootTest}.
  *
  * @author Andy Wilkinson
- * @see SpringBootTestContextCustomizer
+ * @see TestRestTemplateTestContextCustomizer
  */
-class SpringBootTestContextCustomizerFactory implements ContextCustomizerFactory {
+class TestRestTemplateTestContextCustomizerFactory implements ContextCustomizerFactory {
 
 	@Override
 	public ContextCustomizer createContextCustomizer(Class<?> testClass,
 			List<ContextConfigurationAttributes> configAttributes) {
 		if (AnnotatedElementUtils.findMergedAnnotation(testClass,
 				SpringBootTest.class) != null) {
-			return new SpringBootTestContextCustomizer();
+			return new TestRestTemplateTestContextCustomizer();
 		}
 		return null;
 	}

spring-boot-project/spring-boot-test/src/main/resources/META-INF/spring.factories

 # Spring Test ContextCustomizerFactories
 org.springframework.test.context.ContextCustomizerFactory=\
 org.springframework.boot.test.context.ImportsContextCustomizerFactory,\
-org.springframework.boot.test.context.SpringBootTestContextCustomizerFactory,\
 org.springframework.boot.test.context.filter.ExcludeFilterContextCustomizerFactory,\
 org.springframework.boot.test.json.DuplicateJsonObjectContextCustomizerFactory,\
 org.springframework.boot.test.mock.mockito.MockitoContextCustomizerFactory,\
+org.springframework.boot.test.web.client.TestRestTemplateTestContextCustomizerFactory,\
 org.springframework.boot.test.web.reactive.WebTestClientContextCustomizerFactory
 
 # Test Execution Listeners

spring-boot-project/spring-boot-test/src/test/java/org/springframework/boot/test/web/client/NoTestRestTemplateBeanChecker.java

+/*
+ * Copyright 2012-2018 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.boot.test.web.client;
+
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.BeanFactory;
+import org.springframework.beans.factory.BeanFactoryAware;
+import org.springframework.beans.factory.BeanFactoryUtils;
+import org.springframework.beans.factory.ListableBeanFactory;
+import org.springframework.context.annotation.ImportSelector;
+import org.springframework.core.type.AnnotationMetadata;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * {@link ImportSelector} to check no {@link TestRestTemplate} definition is registered
+ * when config classes are processed.
+ */
+class NoTestRestTemplateBeanChecker implements ImportSelector, BeanFactoryAware {
+
+	@Override
+	public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
+		assertThat(BeanFactoryUtils.beanNamesForTypeIncludingAncestors(
+				(ListableBeanFactory) beanFactory, TestRestTemplate.class)).isEmpty();
+	}
+
+	@Override
+	public String[] selectImports(AnnotationMetadata importingClassMetadata) {
+		return new String[0];
+	}
+
+}

spring-boot-project/spring-boot-test/src/test/java/org/springframework/boot/test/web/client/TestRestTemplateTestContextCustomizerIntegrationTests.java

+/*
+ * Copyright 2012-2018 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.boot.test.web.client;
+
+import java.io.IOException;
+import java.io.PrintWriter;
+
+import javax.servlet.GenericServlet;
+import javax.servlet.ServletException;
+import javax.servlet.ServletRequest;
+import javax.servlet.ServletResponse;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.test.context.SpringBootTest.WebEnvironment;
+import org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Import;
+import org.springframework.test.annotation.DirtiesContext;
+import org.springframework.test.context.junit4.SpringRunner;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Integration test for {@link TestRestTemplateTestContextCustomizer}.
+ *
+ * @author Phillip Webb
+ */
+@RunWith(SpringRunner.class)
+@SpringBootTest(webEnvironment = WebEnvironment.RANDOM_PORT)
+@DirtiesContext
+public class TestRestTemplateTestContextCustomizerIntegrationTests {
+
+	@Autowired
+	private TestRestTemplate restTemplate;
+
+	@Test
+	public void test() {
+		assertThat(this.restTemplate.getForObject("/", String.class)).contains("hello");
+	}
+
+	@Configuration
+	@Import({ TestServlet.class, NoTestRestTemplateBeanChecker.class })
+	static class TestConfig {
+
+		@Bean
+		public TomcatServletWebServerFactory webServerFactory() {
+			return new TomcatServletWebServerFactory(0);
+		}
+
+	}
+
+	static class TestServlet extends GenericServlet {
+
+		@Override
+		public void service(ServletRequest request, ServletResponse response)
+				throws ServletException, IOException {
+			try (PrintWriter writer = response.getWriter()) {
+				writer.println("hello");
+			}
+		}
+
+	}
+
+}

spring-boot-project/spring-boot-test/src/test/java/org/springframework/boot/test/web/client/TestRestTemplateTestContextCustomizerWithOverrideIntegrationTests.java

+/*
+ * Copyright 2012-2018 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.boot.test.web.client;
+
+import java.io.IOException;
+import java.io.PrintWriter;
+
+import javax.servlet.GenericServlet;
+import javax.servlet.ServletException;
+import javax.servlet.ServletRequest;
+import javax.servlet.ServletResponse;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.test.context.SpringBootTest.WebEnvironment;
+import org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Import;
+import org.springframework.test.annotation.DirtiesContext;
+import org.springframework.test.context.junit4.SpringRunner;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Integration test for {@link TestRestTemplateTestContextCustomizer} with a custom
+ * {@link TestRestTemplate} bean.
+ *
+ * @author Phillip Webb
+ */
+@RunWith(SpringRunner.class)
+@SpringBootTest(webEnvironment = WebEnvironment.RANDOM_PORT)
+@DirtiesContext
+public class TestRestTemplateTestContextCustomizerWithOverrideIntegrationTests {
+
+	@Autowired
+	private TestRestTemplate restTemplate;
+
+	@Test
+	public void test() {
+		assertThat(this.restTemplate).isInstanceOf(CustomTestRestTemplate.class);
+	}
+
+	@Configuration
+	@Import({ TestServlet.class, NoTestRestTemplateBeanChecker.class })
+	static class TestConfig {
+
+		@Bean
+		public TomcatServletWebServerFactory webServerFactory() {
+			return new TomcatServletWebServerFactory(0);
+		}
+
+		@Bean
+		public TestRestTemplate template() {
+			return new CustomTestRestTemplate();
+		}
+
+	}
+
+	static class TestServlet extends GenericServlet {
+
+		@Override
+		public void service(ServletRequest request, ServletResponse response)
+				throws ServletException, IOException {
+			try (PrintWriter writer = response.getWriter()) {
+				writer.println("hello");
+			}
+		}
+
+	}
+
+	static class CustomTestRestTemplate extends TestRestTemplate {
+
+	}
+
+}