Add /logfile MVC actuator endpoint

Add a `/logfile` endpoint which can be used to fetch the contents of
the log file (if one is being used).

Fixes gh-2137
Closes gh-2294

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/EndpointWebMvcAutoConfiguration.java

@@ -45,6 +45,7 @@ import org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping;
 import org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMappingCustomizer;
 import org.springframework.boot.actuate.endpoint.mvc.EnvironmentMvcEndpoint;
 import org.springframework.boot.actuate.endpoint.mvc.HealthMvcEndpoint;
+import org.springframework.boot.actuate.endpoint.mvc.LogFileMvcEndpoint;
 import org.springframework.boot.actuate.endpoint.mvc.MetricsMvcEndpoint;
 import org.springframework.boot.actuate.endpoint.mvc.MvcEndpoint;
 import org.springframework.boot.actuate.endpoint.mvc.MvcEndpoints;
@@ -90,6 +91,7 @@ import org.springframework.web.servlet.DispatcherServlet;
  * @author Phillip Webb
  * @author Christian Dupuis
  * @author Andy Wilkinson
+ * @author Johannes Stelzer
  */
 @Configuration
 @ConditionalOnClass({ Servlet.class, DispatcherServlet.class })
@@ -219,6 +221,12 @@ public class EndpointWebMvcAutoConfiguration implements ApplicationContextAware,
 		return new MetricsMvcEndpoint(delegate);
 	}
 
+	@Bean
+	@ConditionalOnEnabledEndpoint("logfile")
+	public LogFileMvcEndpoint logfileMvcEndpoint() {
+		return new LogFileMvcEndpoint();
+	}
+
 	@Bean
 	@ConditionalOnBean(ShutdownEndpoint.class)
 	@ConditionalOnEnabledEndpoint(value = "shutdown", enabledByDefault = false)

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/EndpointMvcAdapter.java

@@ -16,11 +16,7 @@
 
 package org.springframework.boot.actuate.endpoint.mvc;
 
-import java.util.Collections;
-import java.util.Map;
-
 import org.springframework.boot.actuate.endpoint.Endpoint;
-import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.util.Assert;
 import org.springframework.web.bind.annotation.RequestMapping;
@@ -35,10 +31,6 @@ import org.springframework.web.bind.annotation.ResponseBody;
  */
 public class EndpointMvcAdapter implements MvcEndpoint {
 
-	private final ResponseEntity<Map<String, String>> disabledResponse = new ResponseEntity<Map<String, String>>(
-			Collections.singletonMap("message", "This endpoint is disabled"),
-			HttpStatus.NOT_FOUND);
-
 	private final Endpoint<?> delegate;
 
 	/**
@@ -54,9 +46,8 @@ public class EndpointMvcAdapter implements MvcEndpoint {
 	@ResponseBody
 	public Object invoke() {
 		if (!this.delegate.isEnabled()) {
-			// Shouldn't happen - MVC endpoint shouldn't be registered when delegate's
-			// disabled
-			return this.disabledResponse;
+			// Shouldn't happen - shouldn't be registered when delegate's disabled
+			return getDisabledResponse();
 		}
 		return this.delegate.invoke();
 	}
@@ -89,7 +80,7 @@ public class EndpointMvcAdapter implements MvcEndpoint {
 	 * @return The response to be returned when the endpoint is disabled
 	 */
 	protected ResponseEntity<?> getDisabledResponse() {
-		return this.disabledResponse;
+		return MvcEndpoint.DISABLED_RESPONSE;
 	}
 
 }

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/LogFileMvcEndpoint.java

@@ -0,0 +1,152 @@
+/*
+ * Copyright 2012-2015 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.endpoint.mvc;
+
+import java.io.IOException;
+
+import javax.validation.constraints.NotNull;
+import javax.validation.constraints.Pattern;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.springframework.boot.actuate.endpoint.Endpoint;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.boot.logging.LogFile;
+import org.springframework.context.EnvironmentAware;
+import org.springframework.core.env.Environment;
+import org.springframework.core.io.FileSystemResource;
+import org.springframework.core.io.Resource;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.http.ResponseEntity.BodyBuilder;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.ResponseBody;
+
+/**
+ * Controller that provides an API for logfiles, i.e. downloading the main logfile
+ * configured in environment property 'logging.file' that is standard, but optional
+ * property for spring-boot applications.
+ *
+ * @author Johannes Stelzer
+ * @author Phillip Webb
+ * @since 1.3.0
+ */
+@ConfigurationProperties(prefix = "endpoints.logfile")
+public class LogFileMvcEndpoint implements MvcEndpoint, EnvironmentAware {
+
+	private static final Log logger = LogFactory.getLog(LogFileMvcEndpoint.class);
+
+	/**
+	 * Endpoint URL path.
+	 */
+	@NotNull
+	@Pattern(regexp = "/[^/]*", message = "Path must start with /")
+	private String path = "/logfile";
+
+	/**
+	 * Enable security on the endpoint.
+	 */
+
+	private boolean sensitive = true;
+
+	/**
+	 * Enable the endpoint.
+	 */
+
+	private boolean enabled = true;
+
+	private Environment environment;
+
+	@Override
+	public void setEnvironment(Environment environment) {
+		this.environment = environment;
+	}
+
+	@Override
+	public String getPath() {
+		return this.path;
+	}
+
+	public void setPath(String path) {
+		this.path = path;
+	}
+
+	@Override
+	public boolean isSensitive() {
+		return this.sensitive;
+	}
+
+	public void setSensitive(boolean sensitive) {
+		this.sensitive = sensitive;
+	}
+
+	public boolean isEnabled() {
+		return this.enabled;
+	}
+
+	public void setEnabled(boolean enabled) {
+		this.enabled = enabled;
+	}
+
+	@Override
+	@SuppressWarnings("rawtypes")
+	public Class<? extends Endpoint> getEndpointType() {
+		return null;
+	}
+
+	@RequestMapping(method = RequestMethod.HEAD)
+	@ResponseBody
+	public ResponseEntity<?> available() {
+		return getResponse(false);
+	}
+
+	@RequestMapping(method = RequestMethod.GET)
+	@ResponseBody
+	public ResponseEntity<?> invoke() throws IOException {
+		return getResponse(true);
+	}
+
+	private ResponseEntity<?> getResponse(boolean includeBody) {
+		if (!isEnabled()) {
+			return (includeBody ? DISABLED_RESPONSE : ResponseEntity.notFound().build());
+		}
+		Resource resource = getLogFileResource();
+		if (resource == null) {
+			return ResponseEntity.notFound().build();
+		}
+		BodyBuilder response = ResponseEntity.ok().contentType(MediaType.TEXT_PLAIN);
+		return (includeBody ? response.body(resource) : response.build());
+	}
+
+	private Resource getLogFileResource() {
+		LogFile logFile = LogFile.get(this.environment);
+		if (logFile == null) {
+			logger.debug("Missing 'logging.file' or 'logging.path' properties");
+			return null;
+		}
+		FileSystemResource resource = new FileSystemResource(logFile.toString());
+		if (!resource.exists()) {
+			if (logger.isWarnEnabled()) {
+				logger.debug("Log file '" + resource + "' does not exist");
+			}
+			return null;
+		}
+		return resource;
+	}
+
+}

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/MvcEndpoint.java

@@ -16,7 +16,12 @@
 
 package org.springframework.boot.actuate.endpoint.mvc;
 
+import java.util.Collections;
+import java.util.Map;
+
 import org.springframework.boot.actuate.endpoint.Endpoint;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
 
 /**
  * A strategy for the MVC layer on top of an {@link Endpoint}. Implementations are allowed
@@ -29,6 +34,10 @@ import org.springframework.boot.actuate.endpoint.Endpoint;
  */
 public interface MvcEndpoint {
 
+	public static final ResponseEntity<Map<String, String>> DISABLED_RESPONSE = new ResponseEntity<Map<String, String>>(
+			Collections.singletonMap("message", "This endpoint is disabled"),
+			HttpStatus.NOT_FOUND);
+
 	/**
 	 * Return the MVC path of the endpoint.
 	 * @return the endpoint path

spring-boot-actuator/src/test/java/org/springframework/boot/actuate/autoconfigure/EndpointWebMvcAutoConfigurationTests.java

@@ -294,7 +294,7 @@ public class EndpointWebMvcAutoConfigurationTests {
 		this.applicationContext.refresh();
 		// /health, /metrics, /env (/shutdown is disabled by default)
 		assertThat(this.applicationContext.getBeansOfType(MvcEndpoint.class).size(),
-				is(equalTo(3)));
+				is(equalTo(4)));
 	}
 
 	@Test

spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/mvc/JolokiaMvcEndpointTests.java

@@ -18,6 +18,7 @@ package org.springframework.boot.actuate.endpoint.mvc;
 
 import java.util.Set;
 
+import org.hamcrest.Matcher;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -40,8 +41,9 @@ import org.springframework.web.context.WebApplicationContext;
 import org.springframework.web.servlet.config.annotation.EnableWebMvc;
 
 import static org.hamcrest.Matchers.containsString;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
+import static org.hamcrest.Matchers.hasItem;
+import static org.hamcrest.Matchers.instanceOf;
+import static org.junit.Assert.assertThat;
 import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
@@ -73,10 +75,10 @@ public class JolokiaMvcEndpointTests {
 	}
 
 	@Test
+	@SuppressWarnings({ "rawtypes", "unchecked" })
 	public void endpointRegistered() throws Exception {
 		Set<? extends MvcEndpoint> values = this.endpoints.getEndpoints();
-		assertEquals(1, values.size());
-		assertTrue(values.iterator().next() instanceof JolokiaMvcEndpoint);
+		assertThat(values, (Matcher) hasItem(instanceOf(JolokiaMvcEndpoint.class)));
 	}
 
 	@Test

spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/mvc/LogFileMvcEndpointTests.java

@@ -0,0 +1,104 @@
+/*
+ * Copyright 2013-2015 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.endpoint.mvc;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
+import org.springframework.core.io.Resource;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.mock.env.MockEnvironment;
+import org.springframework.util.FileCopyUtils;
+
+import static org.hamcrest.Matchers.equalTo;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThat;
+
+/**
+ * Tests for {@link LogFileMvcEndpoint}.
+ *
+ * @author Johannes Stelzer
+ * @author Phillip Webb
+ */
+public class LogFileMvcEndpointTests {
+
+	@Rule
+	public TemporaryFolder temp = new TemporaryFolder();
+
+	private LogFileMvcEndpoint mvc;
+
+	private MockEnvironment environment;
+
+	private File logFile;
+
+	@Before
+	public void before() throws IOException {
+		this.logFile = this.temp.newFile();
+		FileCopyUtils.copy("--TEST--".getBytes(), this.logFile);
+		this.environment = new MockEnvironment();
+		this.mvc = new LogFileMvcEndpoint();
+		this.mvc.setEnvironment(this.environment);
+	}
+
+	@After
+	public void after() {
+		new File("test.log").delete();
+	}
+
+	@Test
+	public void notAvailableWithoutLogFile() throws IOException {
+		assertThat(this.mvc.available().getStatusCode(), equalTo(HttpStatus.NOT_FOUND));
+	}
+
+	@Test
+	public void notAvailableWithMissingLogFile() throws Exception {
+		this.environment.setProperty("logging.file", "no_test.log");
+		assertThat(this.mvc.available().getStatusCode(), equalTo(HttpStatus.NOT_FOUND));
+	}
+
+	@Test
+	public void availableWithLogFile() throws Exception {
+		this.environment.setProperty("logging.file", this.logFile.getAbsolutePath());
+		assertThat(this.mvc.available().getStatusCode(), equalTo(HttpStatus.OK));
+	}
+
+	@Test
+	public void notAvailableIfDisabled() throws Exception {
+		this.environment.setProperty("logging.file", this.logFile.getAbsolutePath());
+		this.mvc.setEnabled(false);
+		assertThat(this.mvc.available().getStatusCode(), equalTo(HttpStatus.NOT_FOUND));
+	}
+
+	@Test
+	public void invokeGetsContent() throws IOException {
+		this.environment.setProperty("logging.file", this.logFile.getAbsolutePath());
+		ResponseEntity<?> response = this.mvc.invoke();
+		assertEquals(HttpStatus.OK, response.getStatusCode());
+		InputStream inputStream = ((Resource) response.getBody()).getInputStream();
+		InputStreamReader reader = new InputStreamReader(inputStream);
+		assertEquals("--TEST--", FileCopyUtils.copyToString(reader));
+	}
+
+}

spring-boot-docs/src/main/asciidoc/appendix-application-properties.adoc

@@ -643,6 +643,9 @@ content into your application; rather pick only the properties that you need.
 	endpoints.info.id=info
 	endpoints.info.sensitive=false
 	endpoints.info.enabled=true
+	endpoints.logfile.path=/logfile
+	endpoints.logfile.sensitive=true
+	endpoints.logfile.enabled=true
 	endpoints.mappings.enabled=true
 	endpoints.mappings.id=mappings
 	endpoints.mappings.sensitive=true

spring-boot-docs/src/main/asciidoc/production-ready-features.adoc

@@ -94,6 +94,11 @@ unauthenticated connection or full message details when authenticated).
 |Displays arbitrary application info.
 |false
 
+|`logfile`
+|Returns the contents of the logfile (if `logging.file` or `logging.path` properties have
+been set). Only available via MVC.
+|true
+
 |`metrics`
 |Shows '`metrics`' information for the current application.
 |true