Spring Boot Actuator 使用
转载于：https://www.jianshu.com/p/af9738634a21
Spring Boot 的 Actuator 提供了很多生产级的特性，比如监控和度量Spring Boot 应用程序。Actuator 的这些特性可以通过众多 REST 接口、远程 shell 和 JMX 获得。
一、Actuator 的 REST 接口
Spring Boot Actuator 的关键特性是在应用程序里提供众多 Web 接口，通过它们了解应用程序运行时的内部状况。Actuator 提供了 13 个接口，可以分为三大类：配置接口、度量接口和其它接口，具体如下表所示。
| HTTP 方法 | 路径 | 描述 |
|---|---|---|
| GET | /autoconfig | 提供了一份自动配置报告，记录哪些自动配置条件通过了，哪些没通过 |
| GET | /configprops | 描述配置属性(包含默认值)如何注入Bean |
| GET | /beans | 描述应用程序上下文里全部的Bean，以及它们的关系 |
| GET | /dump | 获取线程活动的快照 |
| GET | /env | 获取全部环境属性 |
| GET | /env/{name} | 根据名称获取特定的环境属性值 |
| GET | /health | 报告应用程序的健康指标，这些值由HealthIndicator的实现类提供 |
| GET | /info | 获取应用程序的定制信息，这些信息由info打头的属性提供 |
| GET | /mappings | 描述全部的URI路径，以及它们和控制器(包含Actuator端点)的映射关系 |
| GET | /metrics | 报告各种应用程序度量信息，比如内存用量和HTTP请求计数 |
| GET | /metrics/{name} | 报告指定名称的应用程序度量值 |
| POST | /shutdown | 关闭应用程序，要求endpoints.shutdown.enabled设置为true |
| GET | /trace | 提供基本的HTTP请求跟踪信息(时间戳、HTTP头等) |
要启用 Actuator 的端点，只要在项目中引入 Actuator 的依赖即可。对于 Maven 依赖，引入的依赖是这样的：
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
1. 查看配置明细
Actuator 有一些接口不仅可以显示组件映射关系，还可以告诉你自动配置在配置 Spring 应用程序上下文时做了哪些决策。
1.1 获得 Bean 装配报告
要了解应用程序中 Spring 上下文的情况，最重要的接口就是 /beans。它会返回一个 JSON 文档，描述上下文里每个 bean 的情况，包括其 Java 类型以及注入的其它 bean。返回的信息如下所示：
[
{
"context": "application",
"parent": null,
"beans": [
{
"bean": "demoApplication",
"aliases": [],
"scope": "singleton",
"type": "com.example.DemoApplication$$EnhancerBySpringCGLIB$$88686e04",
"resource": "null",
"dependencies": []
},
{
"bean": "org.springframework.boot.autoconfigure.internalCachingMetadataReaderFactory",
"aliases": [],
"scope": "singleton",
"type": "org.springframework.core.type.classreading.CachingMetadataReaderFactory",
"resource": "null",
"dependencies": []
}
]
}
]
所有的 Bean 条目都有五类信息：
- bean：Spring 应用程序上下文中的 Bean 名称或 ID。
- resource：.class 文件的物理位置，通常是一个 URL，指向构建出的 JAR 文件。这会随着应用程序的构建和运行方式发生变化。
- dependencies：当前 Bean 注入的 Bean ID 列表。
- scope：Bean 的作用域（通常是单例，这也是默认作用域）。
- type：Bean 的 Java 类型。
1.2 详解自动配置
/autoconfig接口能告诉你为什么会有这个 bean ，或者为什么没有这个 bean。
{
"positiveMatches": {
"AuditAutoConfiguration#auditListener": [
{
"condition": "OnBeanCondition",
"message": "@ConditionalOnMissingBean (types: org.springframework.boot.actuate.audit.listener.AbstractAuditListener; SearchStrategy: all) did not find any beans"
}
],
"MultipartAutoConfiguration#multipartConfigElement": [
{
"condition": "OnBeanCondition",
"message": "@ConditionalOnMissingBean (types: javax.servlet.MultipartConfigElement; SearchStrategy: all) did not find any beans"
}
]
},
"negativeMatches": {
"AuditAutoConfiguration#authenticationAuditListener": {
"notMatched": [
{
"condition": "OnClassCondition",
"message": "@ConditionalOnClass did not find required class 'org.springframework.security.authentication.event.AbstractAuthenticationEvent'"
}
],
"matched": []
},
"AuditAutoConfiguration#authorizationAuditListener": {
"notMatched": [
{
"condition": "OnClassCondition",
"message": "@ConditionalOnClass did not find required class 'org.springframework.security.access.event.AbstractAuthorizationEvent'"
}
],
"matched": []
}
}
}
1.3 查看配置属性
/env接口会生成应用程序可用的所有环境属性的列表，无论这些属性是否用到。这其中包括环境变量、JVM 属性、命令行参数，以及 application.properties 或 application.yml 文件提供的属性。
{
"profiles": [],
"server.ports": {
"local.server.port": 8080
},
"servletContextInitParams": {},
"systemProperties": {
"java.runtime.name": "Java(TM) SE Runtime Environment",
"spring.output.ansi.enabled": "always",
"sun.boot.library.path": "/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib",
"java.vm.version": "25.121-b13",
"gopherProxySet": "false",
"java.vm.vendor": "Oracle Corporation",
"java.vendor.url": "http://java.oracle.com/",
"path.separator": ":",
"idea.launcher.port": "7532",
"java.vm.name": "Java HotSpot(TM) 64-Bit Server VM",
"file.encoding.pkg": "sun.io",
"user.country": "CN",
"sun.java.launcher": "SUN_STANDARD",
"sun.os.patch.level": "unknown",
"PID": "2716",
"java.vm.specification.name": "Java Virtual Machine Specification",
"user.dir": "/Users/FlySheep/FlySheep/Code/ServerCode/SpringBoot_Demo/demo",
"java.runtime.version": "1.8.0_121-b13",
"java.awt.graphicsenv": "sun.awt.CGraphicsEnvironment",
"org.jboss.logging.provider": "slf4j",
"java.endorsed.dirs": "/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/endorsed",
"os.arch": "x86_64",
"visualvm.id": "11136812717769",
"java.io.tmpdir": "/var/folders/d6/zn9yrwns46j4pwbl1_mv_6hw0000gn/T/",
"line.separator": "\n",
"java.vm.specification.vendor": "Oracle Corporation",
"os.name": "Mac OS X",
"sun.jnu.encoding": "UTF-8",
"spring.beaninfo.ignore": "true",
"java.library.path": "/Users/FlySheep/Library/Java/Extensions:/Library/Java/Extensions:/Network/Library/Java/Extensions:/System/Library/Java/Extensions:/usr/lib/java:.",
"java.specification.name": "Java Platform API Specification",
"java.class.version": "52.0",
"sun.management.compiler": "HotSpot 64-Bit Tiered Compilers",
"os.version": "10.11",
"user.home": "/Users/FlySheep",
"catalina.useNaming": "false",
"user.timezone": "Asia/Shanghai",
"java.awt.printerjob": "sun.lwawt.macosx.CPrinterJob",
"file.encoding": "UTF-8",
"idea.launcher.bin.path": "/Applications/IntelliJ IDEA.app/Contents/bin",
"java.specification.version": "1.8",
"catalina.home": "/private/var/folders/d6/zn9yrwns46j4pwbl1_mv_6hw0000gn/T/tomcat.6698906163877756728.8080",
"java.class.path": "/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/charsets.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/deploy.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/ext/cldrdata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/ext/dnsns.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/ext/jaccess.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/ext/jfxrt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/ext/localedata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/ext/nashorn.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/ext/sunec.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/ext/sunjce_provider.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/ext/sunpkcs11.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/ext/zipfs.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/javaws.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/jce.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/jfr.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/jfxswt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/jsse.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/management-agent.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/plugin.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/resources.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/rt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/lib/ant-javafx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/lib/dt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/lib/javafx-mx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/lib/jconsole.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/lib/packager.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/lib/sa-jdi.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/lib/tools.jar:/Users/FlySheep/FlySheep/Code/ServerCode/SpringBoot_Demo/demo/target/classes:/Users/FlySheep/.m2/repository/org/springframework/boot/spring-boot-starter-web/1.5.2.RELEASE/spring-boot-starter-web-1.5.2.RELEASE.jar:/Users/FlySheep/.m2/repository/org/springframework/boot/spring-boot-starter/1.5.2.RELEASE/spring-boot-starter-1.5.2.RELEASE.jar:/Users/FlySheep/.m2/repository/org/springframework/boot/spring-boot/1.5.2.RELEASE/spring-boot-1.5.2.RELEASE.jar:/Users/FlySheep/.m2/repository/org/springframework/boot/spring-boot-autoconfigure/1.5.2.RELEASE/spring-boot-autoconfigure-1.5.2.RELEASE.jar:/Users/FlySheep/.m2/repository/org/springframework/boot/spring-boot-starter-logging/1.5.2.RELEASE/spring-boot-starter-logging-1.5.2.RELEASE.jar:/Users/FlySheep/.m2/repository/ch/qos/logback/logback-classic/1.1.11/logback-classic-1.1.11.jar:/Users/FlySheep/.m2/repository/ch/qos/logback/logback-core/1.1.11/logback-core-1.1.11.jar:/Users/FlySheep/.m2/repository/org/slf4j/jcl-over-slf4j/1.7.24/jcl-over-slf4j-1.7.24.jar:/Users/FlySheep/.m2/repository/org/slf4j/jul-to-slf4j/1.7.24/jul-to-slf4j-1.7.24.jar:/Users/FlySheep/.m2/repository/org/slf4j/log4j-over-slf4j/1.7.24/log4j-over-slf4j-1.7.24.jar:/Users/FlySheep/.m2/repository/org/yaml/snakeyaml/1.17/snakeyaml-1.17.jar:/Users/FlySheep/.m2/repository/org/springframework/boot/spring-boot-starter-tomcat/1.5.2.RELEASE/spring-boot-starter-tomcat-1.5.2.RELEASE.jar:/Users/FlySheep/.m2/repository/org/apache/tomcat/embed/tomcat-embed-core/8.5.11/tomcat-embed-core-8.5.11.jar:/Users/FlySheep/.m2/repository/org/apache/tomcat/embed/tomcat-embed-el/8.5.11/tomcat-embed-el-8.5.11.jar:/Users/FlySheep/.m2/repository/org/apache/tomcat/embed/tomcat-embed-websocket/8.5.11/tomcat-embed-websocket-8.5.11.jar:/Users/FlySheep/.m2/repository/org/hibernate/hibernate-validator/5.3.4.Final/hibernate-validator-5.3.4.Final.jar:/Users/FlySheep/.m2/repository/javax/validation/validation-api/1.1.0.Final/validation-api-1.1.0.Final.jar:/Users/FlySheep/.m2/repository/org/jboss/logging/jboss-logging/3.3.0.Final/jboss-logging-3.3.0.Final.jar:/Users/FlySheep/.m2/repository/com/fasterxml/classmate/1.3.3/classmate-1.3.3.jar:/Users/FlySheep/.m2/repository/com/fasterxml/jackson/core/jackson-databind/2.8.7/jackson-databind-2.8.7.jar:/Users/FlySheep/.m2/repository/com/fasterxml/jackson/core/jackson-annotations/2.8.0/jackson-annotations-2.8.0.jar:/Users/FlySheep/.m2/repository/com/fasterxml/jackson/core/jackson-core/2.8.7/jackson-core-2.8.7.jar:/Users/FlySheep/.m2/repository/org/springframework/spring-web/4.3.7.RELEASE/spring-web-4.3.7.RELEASE.jar:/Users/FlySheep/.m2/repository/org/springframework/spring-aop/4.3.7.RELEASE/spring-aop-4.3.7.RELEASE.jar:/Users/FlySheep/.m2/repository/org/springframework/spring-beans/4.3.7.RELEASE/spring-beans-4.3.7.RELEASE.jar:/Users/FlySheep/.m2/repository/org/springframework/spring-context/4.3.7.RELEASE/spring-context-4.3.7.RELEASE.jar:/Users/FlySheep/.m2/repository/org/springframework/spring-webmvc/4.3.7.RELEASE/spring-webmvc-4.3.7.RELEASE.jar:/Users/FlySheep/.m2/repository/org/springframework/spring-expression/4.3.7.RELEASE/spring-expression-4.3.7.RELEASE.jar:/Users/FlySheep/.m2/repository/org/springframework/boot/spring-boot-starter-actuator/1.5.2.RELEASE/spring-boot-starter-actuator-1.5.2.RELEASE.jar:/Users/FlySheep/.m2/repository/org/springframework/boot/spring-boot-actuator/1.5.2.RELEASE/spring-boot-actuator-1.5.2.RELEASE.jar:/Users/FlySheep/.m2/repository/org/slf4j/slf4j-api/1.7.24/slf4j-api-1.7.24.jar:/Users/FlySheep/.m2/repository/org/springframework/spring-core/4.3.7.RELEASE/spring-core-4.3.7.RELEASE.jar:/Applications/IntelliJ IDEA.app/Contents/lib/idea_rt.jar",
"user.name": "FlySheep",
"java.vm.specification.version": "1.8",
"sun.java.command": "com.intellij.rt.execution.application.AppMain com.example.DemoApplication",
"java.home": "/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre",
"sun.arch.data.model": "64",
"user.language": "zh",
"java.specification.vendor": "Oracle Corporation",
"awt.toolkit": "sun.lwawt.macosx.LWCToolkit",
"java.vm.info": "mixed mode",
"java.version": "1.8.0_121",
"java.ext.dirs": "/Users/FlySheep/Library/Java/Extensions:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/ext:/Library/Java/Extensions:/Network/Library/Java/Extensions:/System/Library/Java/Extensions:/usr/lib/java",
"sun.boot.class.path": "/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/resources.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/rt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/sunrsasign.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/jsse.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/jce.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/charsets.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/lib/jfr.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre/classes",
"java.awt.headless": "true",
"java.vendor": "Oracle Corporation",
"catalina.base": "/private/var/folders/d6/zn9yrwns46j4pwbl1_mv_6hw0000gn/T/tomcat.6698906163877756728.8080",
"file.separator": "/",
"java.vendor.url.bug": "http://bugreport.sun.com/bugreport/",
"sun.io.unicode.encoding": "UnicodeBig",
"sun.cpu.endian": "little",
"sun.cpu.isalist": ""
},
"systemEnvironment": {
"PATH": "/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/Library/Java/JavaVirtualMachines/jdk1.7.0_79.jdk/Contents/Home/bin:/usr/local/mysql/bin:/Users/FlySheep/FlySheep/JavaTools/apache-maven-3.3.9/bin/bin",
"SHELL": "/bin/zsh",
"PAGER": "less",
"LSCOLORS": "Gxfxcxdxbxegedabagacad",
"OLDPWD": "/Applications/IntelliJ IDEA.app/Contents/bin",
"USER": "FlySheep",
"VERSIONER_PYTHON_PREFER_32_BIT": "no",
"ZSH": "/Users/FlySheep/.oh-my-zsh",
"TMPDIR": "/var/folders/d6/zn9yrwns46j4pwbl1_mv_6hw0000gn/T/",
"SSH_AUTH_SOCK": "/private/tmp/com.apple.launchd.vZEKsGdZ1T/Listeners",
"JAVA_MAIN_CLASS_2716": "com.intellij.rt.execution.application.AppMain",
"XPC_FLAGS": "0x0",
"VERSIONER_PYTHON_VERSION": "2.7",
"__CF_USER_TEXT_ENCODING": "0x1F5:0x19:0x34",
"Apple_PubSub_Socket_Render": "/private/tmp/com.apple.launchd.5VgRuDCQ5D/Render",
"LOGNAME": "FlySheep",
"LESS": "-R",
"LC_CTYPE": "",
"PWD": "/Users/FlySheep/FlySheep/Code/ServerCode/SpringBoot_Demo/demo",
"XPC_SERVICE_NAME": "com.jetbrains.intellij.136992",
"HOME": "/Users/FlySheep"
},
"applicationConfig: [classpath:/application.properties]": {
"management.security.enabled": "false"
}
}
基本上，任何能给Spring Boot 应用程序提供属性的属性源都会列在 /env 的结果里，同时会显示具体的属性。
为了避免敏感信息暴露到 /env 里，所有名为password、secret、key(或者名字中最后一段是这些)的属性在 /env 里都会加上“*”。举个例子，如果有一个属性名字是database.password，那么它在/env中的显示效果是这样的：
"database.password":"******"
/env 接口还能用来获取单个属性的值，只需要在请求时在 /env 后加上属性名即可。
1.4 查看属性的使用方法
/configprops 接口会生成一个报告，说明属性如何进行设置(注入或其他方式)。
{
"endpoints-org.springframework.boot.actuate.endpoint.EndpointProperties": {
"prefix": "endpoints",
"properties": {
"enabled": true,
"sensitive": null
}
},
"management.info-org.springframework.boot.actuate.autoconfigure.InfoContributorProperties": {
"prefix": "management.info",
"properties": {
"git": {
"mode": "SIMPLE"
}
}
},
"metricsEndpoint": {
"prefix": "endpoints.metrics",
"properties": {
"id": "metrics",
"sensitive": true,
"enabled": true
}
},
"spring.jackson-org.springframework.boot.autoconfigure.jackson.JacksonProperties": {
"prefix": "spring.jackson",
"properties": {
"propertyNamingStrategy": null,
"defaultPropertyInclusion": null,
"dateFormat": null,
"timeZone": null,
"locale": null,
"jodaDateTimeFormat": null
}
},
"heapdumpMvcEndpoint": {
"prefix": "endpoints.heapdump",
"properties": {
"path": "/heapdump",
"sensitive": true,
"enabled": true
}
},
"endpoints.cors-org.springframework.boot.actuate.autoconfigure.EndpointCorsProperties": {
"prefix": "endpoints.cors",
"properties": {
"allowedOrigins": [],
"maxAge": 1800,
"exposedHeaders": [],
"allowedHeaders": [],
"allowedMethods": [],
"allowCredentials": null
}
},
"environmentMvcEndpoint": {
"prefix": "endpoints.env",
"properties": {
"path": "/env"
}
},
"environmentEndpoint": {
"prefix": "endpoints.env",
"properties": {
"id": "env",
"sensitive": true,
"enabled": true
}
},
"spring.http.multipart-org.springframework.boot.autoconfigure.web.MultipartProperties": {
"prefix": "spring.http.multipart",
"properties": {
"maxRequestSize": "10MB",
"fileSizeThreshold": "0",
"location": null,
"maxFileSize": "1MB",
"enabled": true,
"resolveLazily": false
}
},
"spring.info-org.springframework.boot.autoconfigure.info.ProjectInfoProperties": {
"prefix": "spring.info",
"properties": {
"build": {
"location": {}
},
"git": {
"location": {}
}
}
},
"auditEventsEndpoint": {
"prefix": "endpoints.auditevents",
"properties": {
"enabled": true
}
},
"traceEndpoint": {
"prefix": "endpoints.trace",
"properties": {
"id": "trace",
"sensitive": true,
"enabled": true
}
},
"metricsMvcEndpoint": {
"prefix": "endpoints.metrics",
"properties": {
"path": "/metrics"
}
},
"infoEndpoint": {
"prefix": "endpoints.info",
"properties": {
"id": "info",
"sensitive": false,
"enabled": true
}
},
"auditEventMvcEndpoint": {
"prefix": "endpoints.auditevents",
"properties": {
"path": "/auditevents",
"sensitive": true,
"enabled": true
}
},
"management.trace-org.springframework.boot.actuate.trace.TraceProperties": {
"prefix": "management.trace",
"properties": {
"include": [
"COOKIES",
"REQUEST_HEADERS",
"RESPONSE_HEADERS",
"ERRORS"
]
}
},
"spring.resources-org.springframework.boot.autoconfigure.web.ResourceProperties": {
"prefix": "spring.resources",
"properties": {
"cachePeriod": null,
"addMappings": true,
"chain": {
"cache": true,
"htmlApplicationCache": false,
"gzipped": false,
"strategy": {
"fixed": {
"enabled": false,
"paths": [
"/**"
],
"version": null
},
"content": {
"enabled": false,
"paths": [
"/**"
]
}
}
},
"staticLocations": [
"/",
"classpath:/META-INF/resources/",
"classpath:/resources/",
"classpath:/static/",
"classpath:/public/"
]
}
},
"management.health.status-org.springframework.boot.actuate.autoconfigure.HealthIndicatorProperties": {
"prefix": "management.health.status",
"properties": {
"order": null
}
},
"healthMvcEndpoint": {
"prefix": "endpoints.health",
"properties": {
"path": "/health"
}
},
"serverProperties": {
"prefix": "server",
"properties": {
"address": null,
"maxHttpPostSize": 0,
"undertow": {
"maxHttpPostSize": 0,
"bufferSize": null,
"buffersPerRegion": null,
"ioThreads": null,
"workerThreads": null,
"directBuffers": null,
"accesslog": {
"enabled": null,
"pattern": "common",
"prefix": "access_log.",
"suffix": "log",
"dir": "/Users/FlySheep/FlySheep/Code/ServerCode/SpringBoot_Demo/demo/logs",
"rotate": true
}
},
"tomcat": {
"accesslog": {
"enabled": false,
"pattern": "common",
"directory": "logs",
"prefix": "access_log",
"suffix": ".log",
"rotate": true,
"renameOnRotate": false,
"requestAttributesEnabled": false,
"buffered": true
},
"internalProxies": "10\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}|192\\.168\\.\\d{1,3}\\.\\d{1,3}|169\\.254\\.\\d{1,3}\\.\\d{1,3}|127\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}|172\\.1[6-9]{1}\\.\\d{1,3}\\.\\d{1,3}|172\\.2[0-9]{1}\\.\\d{1,3}\\.\\d{1,3}|172\\.3[0-1]{1}\\.\\d{1,3}\\.\\d{1,3}",
"protocolHeader": null,
"protocolHeaderHttpsValue": "https",
"portHeader": "X-Forwarded-Port",
"remoteIpHeader": null,
"basedir": null,
"backgroundProcessorDelay": 30,
"maxThreads": 0,
"minSpareThreads": 0,
"maxHttpPostSize": 0,
"redirectContextRoot": null,
"uriEncoding": null,
"maxConnections": 0,
"acceptCount": 0,
"additionalTldSkipPatterns": []
},
"displayName": "application",
"session": {
"timeout": null,
"trackingModes": null,
"persistent": false,
"storeDir": null,
"cookie": {
"name": null,
"domain": null,
"path": null,
"comment": null,
"httpOnly": null,
"secure": null,
"maxAge": null
}
},
"contextPath": null,
"error": {
"path": "/error",
"includeStacktrace": "NEVER"
},
"ssl": null,
"serverHeader": null,
"useForwardHeaders": null,
"port": null,
"maxHttpHeaderSize": 0,
"servletPath": "/",
"jspServlet": null,
"jetty": {
"maxHttpPostSize": 0,
"acceptors": null,
"selectors": null
},
"connectionTimeout": null
}
},
"spring.metrics.export-org.springframework.boot.actuate.metrics.export.MetricExportProperties": {
"prefix": "spring.metrics.export",
"properties": {
"excludes": null,
"statsd": {
"host": null,
"port": 8125,
"prefix": null
},
"includes": null,
"enabled": true,
"redis": {
"prefix": "spring.metrics.application.7a5b013db041f4a1b6c45b6456487d05",
"key": "******"
},
"aggregate": {
"prefix": "application.7a5b013db041f4a1b6c45b6456487d05",
"keyPattern": "k.d"
}
}
},
"configurationPropertiesReportEndpoint": {
"prefix": "endpoints.configprops",
"properties": {
"id": "configprops",
"sensitive": true,
"enabled": true
}
},
"healthEndpoint": {
"prefix": "endpoints.health",
"properties": {
"timeToLive": 1000,
"id": "health",
"sensitive": false,
"enabled": true
}
},
"loggersMvcEndpoint": {
"prefix": "endpoints.loggers",
"properties": {
"path": "/loggers"
}
},
"loggersEndpoint": {
"prefix": "endpoints.loggers",
"properties": {
"id": "loggers",
"sensitive": true,
"enabled": true
}
},
"endpoints.metrics.filter-org.springframework.boot.actuate.autoconfigure.MetricFilterProperties": {
"prefix": "endpoints.metrics.filter",
"properties": {
"counterSubmissions": [
"MERGED"
],
"gaugeSubmissions": [
"MERGED"
]
}
},
"dumpEndpoint": {
"prefix": "endpoints.dump",
"properties": {
"id": "dump",
"sensitive": true,
"enabled": true
}
},
"autoConfigurationReportEndpoint": {
"prefix": "endpoints.autoconfig",
"properties": {
"id": "autoconfig",
"sensitive": true,
"enabled": true
}
},
"endpoints.jmx-org.springframework.boot.actuate.autoconfigure.EndpointMBeanExportProperties": {
"prefix": "endpoints.jmx",
"properties": {
"uniqueNames": false,
"enabled": true,
"domain": ""
}
},
"spring.http.encoding-org.springframework.boot.autoconfigure.web.HttpEncodingProperties": {
"prefix": "spring.http.encoding",
"properties": {
"charset": "UTF-8",
"force": false,
"mapping": null,
"forceRequest": false,
"forceResponse": false
}
},
"shutdownEndpoint": {
"prefix": "endpoints.shutdown",
"properties": {
"id": "shutdown",
"sensitive": true,
"enabled": false
}
},
"beansEndpoint": {
"prefix": "endpoints.beans",
"properties": {
"id": "beans",
"sensitive": true,
"enabled": true
}
},
"managementServerProperties": {
"prefix": "management",
"properties": {
"security": {
"enabled": false,
"roles": [
"ACTUATOR"
],
"sessions": "STATELESS"
},
"address": null,
"port": null,
"addApplicationContextHeader": true,
"contextPath": "",
"ssl": null
}
},
"requestMappingEndpoint": {
"prefix": "endpoints.mappings",
"properties": {
"id": "mappings",
"sensitive": true,
"enabled": true
}
},
"endpoints.health-org.springframework.boot.actuate.autoconfigure.HealthMvcEndpointProperties": {
"prefix": "endpoints.health",
"properties": {
"mapping": {}
}
},
"spring.mvc-org.springframework.boot.autoconfigure.web.WebMvcProperties": {
"prefix": "spring.mvc",
"properties": {
"dateFormat": null,
"servlet": {
"loadOnStartup": -1
},
"staticPathPattern": "/**",
"dispatchOptionsRequest": true,
"dispatchTraceRequest": false,
"locale": null,
"ignoreDefaultModelOnRedirect": true,
"logResolvedException": false,
"async": {
"requestTimeout": null
},
"messageCodesResolverFormat": null,
"mediaTypes": {},
"view": {
"prefix": null,
"suffix": null
},
"localeResolver": "ACCEPT_HEADER",
"throwExceptionIfNoHandlerFound": false
}
},
"diskSpaceHealthIndicatorProperties": {
"prefix": "management.health.diskspace",
"properties": {
"path": "/Users/FlySheep/FlySheep/Code/ServerCode/SpringBoot_Demo/demo/.",
"threshold": 10485760
}
}
}
1.5 生成接口道控制器的映射
在应用程序相对较小的时候，很容易搞清楚控制器都映射到了哪些接口上。如果Web界面的控制器和请求处理方法数量多，那最好能有一个列表，罗列出应用程序发布的全部接口。/mappings 接口就提供了这么一个列表。
{
"/webjars/**": {
"bean": "resourceHandlerMapping"
},
"/**": {
"bean": "resourceHandlerMapping"
},
"/**/favicon.ico": {
"bean": "faviconHandlerMapping"
},
"{[/error]}": {
"bean": "requestMappingHandlerMapping",
"method": "public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)"
},
"{[/error],produces=[text/html]}": {
"bean": "requestMappingHandlerMapping",
"method": "public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)"
},
"{[/env/{name:.*}],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}": {
"bean": "endpointHandlerMapping",
"method": "public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EnvironmentMvcEndpoint.value(java.lang.String)"
},
"{[/env || /env.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}": {
"bean": "endpointHandlerMapping",
"method": "public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()"
},
"{[/beans || /beans.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}": {
"bean": "endpointHandlerMapping",
"method": "public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()"
},
"{[/auditevents || /auditevents.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}": {
"bean": "endpointHandlerMapping",
"method": "public org.springframework.http.ResponseEntity<?> org.springframework.boot.actuate.endpoint.mvc.AuditEventsMvcEndpoint.findByPrincipalAndAfterAndType(java.lang.String,java.util.Date,java.lang.String)"
},
"{[/autoconfig || /autoconfig.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}": {
"bean": "endpointHandlerMapping",
"method": "public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()"
},
"{[/loggers/{name:.*}],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}": {
"bean": "endpointHandlerMapping",
"method": "public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.LoggersMvcEndpoint.get(java.lang.String)"
},
"{[/loggers/{name:.*}],methods=[POST],consumes=[application/vnd.spring-boot.actuator.v1+json || application/json],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}": {
"bean": "endpointHandlerMapping",
"method": "public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.LoggersMvcEndpoint.set(java.lang.String,java.util.Map<java.lang.String, java.lang.String>)"
},
"{[/loggers || /loggers.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}": {
"bean": "endpointHandlerMapping",
"method": "public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()"
},
"{[/heapdump || /heapdump.json],methods=[GET],produces=[application/octet-stream]}": {
"bean": "endpointHandlerMapping",
"method": "public void org.springframework.boot.actuate.endpoint.mvc.HeapdumpMvcEndpoint.invoke(boolean,javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse) throws java.io.IOException,javax.servlet.ServletException"
},
"{[/mappings || /mappings.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}": {
"bean": "endpointHandlerMapping",
"method": "public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()"
},
"{[/trace || /trace.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}": {
"bean": "endpointHandlerMapping",
"method": "public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()"
},
"{[/configprops || /configprops.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}": {
"bean": "endpointHandlerMapping",
"method": "public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()"
},
"{[/dump || /dump.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}": {
"bean": "endpointHandlerMapping",
"method": "public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()"
},
"{[/metrics/{name:.*}],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}": {
"bean": "endpointHandlerMapping",
"method": "public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.MetricsMvcEndpoint.value(java.lang.String)"
},
"{[/metrics || /metrics.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}": {
"bean": "endpointHandlerMapping",
"method": "public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()"
},
"{[/health || /health.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}": {
"bean": "endpointHandlerMapping",
"method": "public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.HealthMvcEndpoint.invoke(javax.servlet.http.HttpServletRequest,java.security.Principal)"
},
"{[/info || /info.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}": {
"bean": "endpointHandlerMapping",
"method": "public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()"
}
}
这里我们可以看到不少接口的映射。每个映射的键都是一个字符串，其内容就是 Spring MVC 的 @RequestMapping 注解上设置的属性。实际上，这个字符串能让你清晰地了解控制器是如何映射的，哪怕不看源代码。每个映射的值都有两个属性：bean 和 method。bean 属性标识了 Spring Bean 的名字，映射源自这个Bean。method属性是映射对应方法的全限定方法签名。
2. 运行时指标
对运行时指标情况做一个快照，这对评估应用程序的健康情况很有帮助。Actuator 提供了一系列接口，让你能在运行时快速检查应用程序。
2.1 查看应用程序的指标值
关于运行中的应用程序，有很多有趣而且有用的信息。举个例子，了解应用程序的内存情况 (可用或空闲)有助于决定给JVM分配多少内存。对Web应用程序而言，不用查看Web服务器日志，如果请求失败或者是耗时太长，就可以大概知道内存的情况了。运行中的应用程序有诸多计数器和度量器，/metrics 接口提供了这些东西的快照。
{
"mem": 365004,
"mem.free": 153938,
"processors": 8,
"instance.uptime": 852279,
"uptime": 855002,
"systemload.average": 3.509765625,
"heap.committed": 316928,
"heap.init": 262144,
"heap.used": 162989,
"heap": 3728384,
"nonheap.committed": 50816,
"nonheap.init": 2496,
"nonheap.used": 48077,
"nonheap": 0,
"threads.peak": 18,
"threads.daemon": 16,
"threads.totalStarted": 23,
"threads": 18,
"classes": 5974,
"classes.loaded": 5974,
"classes.unloaded": 0,
"gc.ps_scavenge.count": 4,
"gc.ps_scavenge.time": 35,
"gc.ps_marksweep.count": 1,
"gc.ps_marksweep.time": 27,
"httpsessions.max": -1,
"httpsessions.active": 0,
"gauge.response.mappings": 4,
"gauge.response.configprops": 155,
"counter.status.200.mappings": 1,
"counter.status.200.configprops": 1
}
对 /metrics 接口提供的信息进行简单分类如下表：
| 分类 | 前缀 | 报告内容 |
|---|---|---|
| 垃圾收集器 | gc.* | 已经发生过的垃圾收集次数，以及垃圾收集所耗费的时间，适用于标记-清理垃圾收集器和并行垃圾收集器(数据源自java.lang.management. GarbageCollectorMXBean) |
| 内存 | mem.* | 分配给应用程序的内存数量和空闲的内存数量(数据源自java.lang. Runtime) |
| 堆 | heap.* | 当前内存用量(数据源自java.lang.management.MemoryUsage) |
| 类加载器 | classes.* | JVM类加载器加载与卸载的类的数量(数据源自java.lang. management.ClassLoadingMXBean) |
| 系统 | processors、instance.uptime、uptime、systemload.average | 系统信息，例如处理器数量(数据源自java.lang.Runtime)、运行时间(数据源自java.lang.management.RuntimeMXBean)、平均负载(数据源自java.lang.management.OperatingSystemMXBean) |
| 线程池 | thread.* | 线程、守护线程的数量，以及JVM启动后的线程数量峰值(数据源自 java.lang .management.ThreadMXBean) |
| 数据源 | datasource.* | 数据源连接的数量(源自数据源的元数据，仅当Spring应用程序上下文里存在 DataSource Bean 的时候才会有这个信息) |
| Tomcat 会话 | httpsessions.* | Tomcat的活跃会话数和最大会话数(数据源自嵌入式Tomcat的Bean，仅在使用嵌入式Tomcat服务器运行应用程序时才有这个信息) |
| HTTP | counter.status.、gauge.response. | 多种应用程序服务HTTP请求的度量值与计数器 |
请注意，这里的一些度量值，比如数据源和Tomcat会话，仅在应用程序中运行特定组件时才有数据。你还可以注册自己的度量信息。
HTTP的计数器和度量值需要做一点说明。counter.status 后的值是HTTP状态码，随后是所请求的路径。举个例子，counter.status.200.metrics 表明/metrics端点返回 200(OK) 状态码的次数。
HTTP的度量信息在结构上也差不多，却在报告另一类信息。它们全部以gauge.response 开头,，表明这是HTTP响应的度量信息。前缀后是对应的路径。度量值是以毫秒为单位的时间，反映了最近处理该路径请求的耗时。
这里还有几个特殊的值需要注意。root路径指向的是根路径或/。star-star代表了那些Spring 认为是静态资源的路径，包括图片、JavaScript和样式表，其中还包含了那些找不到的资源。这就是为什么你经常会看到 counter.status.404.star-star，这是返回了HTTP 404 (NOT FOUND) 状态的请求数。
/metrics 接口会返回所有的可用度量值，但你也可能只对某个值感兴趣。要获取单个值，请求时可以在URL后加上对应的键名。例如，要查看空闲内存大小,可以向/metrics/mem.free发一 个GET请求。
2.2 追踪 Web 请求
/trace 接口能报告所有Web请求的详细信息，包括请求方法、路径、时间戳以及请求和响应的头信息。
[
{
"timestamp": 1491279254447,
"info": {
"method": "GET",
"path": "/metrics",
"headers": {
"request": {
"host": "localhost:8080",
"connection": "keep-alive",
"upgrade-insecure-requests": "1",
"user-agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.87 Safari/537.36",
"accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8",
"accept-encoding": "gzip, deflate, sdch, br",
"accept-language": "zh-CN,zh;q=0.8,en;q=0.6",
"cookie": "JSESSIONID=24CCB83195B2A35F5193C97D2CD51D69"
},
"response": {
"X-Application-Context": "application",
"Content-Type": "application/vnd.spring-boot.actuator.v1+json;charset=UTF-8",
"Transfer-Encoding": "chunked",
"Date": "Tue, 04 Apr 2017 04:14:14 GMT",
"status": "200"
}
}
}
}
]
2.3 导出线程活动
在确认应用程序运行情况时，除了跟踪请求，了解线程活动也会很有帮助。/dump 接口会生成当前线程活动的快照。
2.4 监控应用程序健康状况
如果你想知道自己的应用程序是否在运行,可以直接访问/health 接口。在最简单的情况下，该端点会显示一个简单的JSON，内容如下:
{
"status": "UP",
"diskSpace": {
"status": "UP",
"total": 48978722816,
"free": 8812167168,
"threshold": 10485760
}
}
二、定制 Actuator
虽然Actuator提供了很多运行中Spring Boot应用程序的内部工作细节，但难免和你的需求有所偏差。也许你并不需要它提供的所有功能，想要关闭一些也说不定。或者，你需要对Actuator 稍作扩展，增加一些自定义的度量信息，以满足你对应用程序的需求。
1. 修改接口 ID
每个Actuator 接口都有一个ID用来决定接口的路径，比方说，/beans接口的默认ID就是beans。比如要修改 /beans 为 /instances，则设置如下：
endpoints.beans.id = instances
2. 启用和禁用接口
虽然Actuator的接口都很有用，但你不一定需要全部这些接口。默认情况下，所有接口(除 了/shutdown)都启用。比如要禁用 /metrics 接口，则可以设置如下：
endpoints.metrics.enabled = false
如果你只想打开一两个接口，那就先禁用全部接口，然后启用那几个你要的，这样更方便。
endpoints.enabled = false
endpoints.metrics.enabled = true
3. 添加自定义度量信息
Actuator 自动配置有两个实例 CounterService 和 GaugeService 可以用来计数使用，我们所要做的就是把它们的实例注入所需的 bean 然后调用相应的方法。除此之外，我们还可以实现 PublicMetrics 接口，提供自己需要的度量信息。
4. 创建自定义跟踪仓库
默认情况下，/trace 接口报告的跟踪信息都存储在内存仓库里，100个条目封顶。一旦仓库满了，就开始移除老的条目，给新的条目腾出空间。在开发阶段这没什么问题，但在生产环境中，大流量会造成跟踪信息还没来得及看就被丢弃。我们可以将那些跟踪条目存储在其他地方——既不消耗内存，又能长久保存的地方。只需实现Spring Boot的TraceRepository接口即可。
5. 插入自定义的健康指示器
实现 HealthIndicator 接口则可以实现自定义的健康指示器。
6. 保护 Actuator 接口
很多Actuator端点发布的信息都可能涉及敏感数据，还有一些端点，(比如/shutdown)非常危险，可以用来关闭应用程序。因此，保护这些端点尤为重要,能访问它们的只能是那些经过授权的客户端。
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