Add @EndpointServlet and migrate Jolokia

Add first class support for Servlet based endpoints and rework the
Jolokia endpoint to use it.

Fixes spring-projectsgh-10264

Author: philwebb

Diff for: spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/endpoint/web/ServletEndpointManagementContextConfiguration.java

@@ -0,0 +1,46 @@
+/*
+ * 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.actuate.autoconfigure.endpoint.web;
+
+import org.springframework.boot.actuate.autoconfigure.web.ManagementContextConfiguration;
+import org.springframework.boot.actuate.endpoint.web.ServletEndpointRegistrar;
+import org.springframework.boot.actuate.endpoint.web.annotation.ServletEndpointsSupplier;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication.Type;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+/**
+ * {@link ManagementContextConfiguration} for servlet endpoints.
+ *
+ * @author Phillip Webb
+ *
+ * @since 2.0.0
+ */
+@Configuration
+@ConditionalOnWebApplication(type = Type.SERVLET)
+public class ServletEndpointManagementContextConfiguration {
+
+	@Bean
+	public ServletEndpointRegistrar servletEndpointRegistrar(
+			WebEndpointProperties properties,
+			ServletEndpointsSupplier servletEndpointsSupplier) {
+		return new ServletEndpointRegistrar(properties.getBasePath(),
+				servletEndpointsSupplier.getEndpoints());
+	}
+
+}

Diff for: spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/endpoint/web/WebEndpointAutoConfiguration.java

@@ -32,19 +32,23 @@
 import org.springframework.boot.actuate.endpoint.invoke.OperationInvokerAdvisor;
 import org.springframework.boot.actuate.endpoint.invoke.ParameterValueMapper;
 import org.springframework.boot.actuate.endpoint.web.EndpointMediaTypes;
+import org.springframework.boot.actuate.endpoint.web.ExposableServletEndpoint;
 import org.springframework.boot.actuate.endpoint.web.ExposableWebEndpoint;
 import org.springframework.boot.actuate.endpoint.web.PathMappedEndpoints;
 import org.springframework.boot.actuate.endpoint.web.PathMapper;
 import org.springframework.boot.actuate.endpoint.web.WebEndpointsSupplier;
 import org.springframework.boot.actuate.endpoint.web.annotation.ControllerEndpointDiscoverer;
 import org.springframework.boot.actuate.endpoint.web.annotation.ControllerEndpointsSupplier;
 import org.springframework.boot.actuate.endpoint.web.annotation.ExposableControllerEndpoint;
+import org.springframework.boot.actuate.endpoint.web.annotation.ServletEndpointDiscoverer;
+import org.springframework.boot.actuate.endpoint.web.annotation.ServletEndpointsSupplier;
 import org.springframework.boot.actuate.endpoint.web.annotation.WebEndpointDiscoverer;
 import org.springframework.boot.autoconfigure.AutoConfigureAfter;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication.Type;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.annotation.Bean;
@@ -138,4 +142,20 @@ public ExposeExcludePropertyEndpointFilter<ExposableControllerEndpoint> controll
 				ExposableControllerEndpoint.class, expose, exclude);
 	}
 
+	@ConditionalOnWebApplication(type = Type.SERVLET)
+	static class WebEndpointServletAutoConfiguration {
+
+		@Bean
+		@ConditionalOnMissingBean(ServletEndpointsSupplier.class)
+		public ServletEndpointDiscoverer servletEndpointDiscoverer(
+				ApplicationContext applicationContext, PathMapper webEndpointPathMapper,
+				ObjectProvider<Collection<OperationInvokerAdvisor>> invokerAdvisors,
+				ObjectProvider<Collection<EndpointFilter<ExposableServletEndpoint>>> filters) {
+			return new ServletEndpointDiscoverer(applicationContext,
+					webEndpointPathMapper,
+					filters.getIfAvailable(Collections::emptyList));
+		}
+
+	}
+
 }

Diff for: spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/jolokia/JolokiaEndpoint.java

@@ -0,0 +1,49 @@
+/*
+ * 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.actuate.autoconfigure.jolokia;
+
+import java.util.Map;
+import java.util.function.Supplier;
+
+import org.jolokia.http.AgentServlet;
+
+import org.springframework.boot.actuate.endpoint.annotation.Endpoint;
+import org.springframework.boot.actuate.endpoint.web.EndpointServlet;
+import org.springframework.boot.actuate.endpoint.web.annotation.ServletEndpoint;
+
+/**
+ * {@link Endpoint} to expose a Jolokia {@link AgentServlet}.
+ *
+ * @author Phillip Webb
+ * @since 2.0.0
+ */
+@ServletEndpoint(id = "jolokia")
+public class JolokiaEndpoint implements Supplier<EndpointServlet> {
+
+	private Map<String, String> initParameters;
+
+	public JolokiaEndpoint(Map<String, String> initParameters) {
+		this.initParameters = initParameters;
+	}
+
+	@Override
+	public EndpointServlet get() {
+		return new EndpointServlet(AgentServlet.class)
+				.withInitParameters(this.initParameters);
+	}
+
+}

Diff for: spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/jolokia/JolokiaEndpointAutoConfiguration.java

@@ -0,0 +1,48 @@
+/*
+ * 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.actuate.autoconfigure.jolokia;
+
+import org.jolokia.http.AgentServlet;
+
+import org.springframework.boot.actuate.autoconfigure.endpoint.condition.ConditionalOnEnabledEndpoint;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication.Type;
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+/**
+ * {@link EnableAutoConfiguration Auto-configuration} for the {@link JolokiaEndpoint}.
+ *
+ * @author Phillip Webb
+ * @since 2.0.0
+ */
+@Configuration
+@ConditionalOnWebApplication(type = Type.SERVLET)
+@ConditionalOnClass(AgentServlet.class)
+@EnableConfigurationProperties(JolokiaProperties.class)
+public class JolokiaEndpointAutoConfiguration {
+
+	@Bean
+	@ConditionalOnEnabledEndpoint
+	public JolokiaEndpoint jolokiaEndpoint(JolokiaProperties properties) {
+		return new JolokiaEndpoint(properties.getConfig());
+	}
+
+}

Diff for: spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/jolokia/JolokiaManagementContextConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * 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.
@@ -29,41 +29,15 @@
  * @author Stephane Nicoll
  * @since 2.0.0
  */
-@ConfigurationProperties(prefix = "management.jolokia")
+@ConfigurationProperties(prefix = "management.endpoint.jolokia")
 public class JolokiaProperties {
 
-	/**
-	 * Whether to enable Jolokia.
-	 */
-	private boolean enabled;
-
-	/**
-	 * Path at which Jolokia is available.
-	 */
-	private String path = "/jolokia";
-
 	/**
 	 * Jolokia settings. These are traditionally set using servlet parameters. Refer to
 	 * the documentation of Jolokia for more details.
 	 */
 	private final Map<String, String> config = new HashMap<>();
 
-	public boolean isEnabled() {
-		return this.enabled;
-	}
-
-	public void setEnabled(boolean enabled) {
-		this.enabled = enabled;
-	}
-
-	public String getPath() {
-		return this.path;
-	}
-
-	public void setPath(String path) {
-		this.path = path;
-	}
-
 	public Map<String, String> getConfig() {
 		return this.config;
 	}

Diff for: spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/jolokia/JolokiaProperties.java

@@ -795,7 +795,7 @@
       "type": "java.lang.String",
       "description": "Endpoint URL path.",
       "deprecation": {
-        "reason": "Endpoint path is no longer customizable.",
+        "replacement": "management.endpoints.web.path-mapping.jolokia",
         "level": "error"
       }
     },
@@ -1734,4 +1734,3 @@
     }
   ]
 }
-

Diff for: spring-boot-project/spring-boot-actuator-autoconfigure/src/main/resources/META-INF/additional-spring-configuration-metadata.json

@@ -23,6 +23,7 @@ org.springframework.boot.actuate.autoconfigure.info.InfoContributorAutoConfigura
 org.springframework.boot.actuate.autoconfigure.info.InfoEndpointAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.jdbc.DataSourceHealthIndicatorAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.jms.JmsHealthIndicatorAutoConfiguration,\
+org.springframework.boot.actuate.autoconfigure.jolokia.JolokiaEndpointAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.ldap.LdapHealthIndicatorAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.liquibase.LiquibaseEndpointAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.logging.LogFileWebEndpointAutoConfiguration,\
@@ -47,10 +48,10 @@ org.springframework.boot.actuate.autoconfigure.web.server.ManagementContextAutoC
 org.springframework.boot.actuate.autoconfigure.web.servlet.ServletManagementContextAutoConfiguration
 
 org.springframework.boot.actuate.autoconfigure.web.ManagementContextConfiguration=\
+org.springframework.boot.actuate.autoconfigure.endpoint.web.ServletEndpointManagementContextConfiguration,\
 org.springframework.boot.actuate.autoconfigure.endpoint.web.reactive.WebFluxEndpointManagementContextConfiguration,\
 org.springframework.boot.actuate.autoconfigure.endpoint.web.servlet.WebMvcEndpointManagementContextConfiguration,\
 org.springframework.boot.actuate.autoconfigure.endpoint.web.jersey.JerseyWebEndpointManagementContextConfiguration,\
-org.springframework.boot.actuate.autoconfigure.jolokia.JolokiaManagementContextConfiguration,\
 org.springframework.boot.actuate.autoconfigure.web.jersey.JerseyManagementChildContextConfiguration,\
 org.springframework.boot.actuate.autoconfigure.web.reactive.ReactiveManagementChildContextConfiguration,\
 org.springframework.boot.actuate.autoconfigure.web.servlet.ServletManagementChildContextConfiguration,\