[[production-ready]] = Spring Boot Actuator: Production-ready features [partintro] -- Spring Boot includes a number of additional features to help you monitor and manage your application when you push it to production. You can choose to manage and monitor your application by using HTTP endpoints or with JMX. Auditing, health, and metrics gathering can also be automatically applied to your application. Actuator HTTP endpoints are only available with a Spring MVC-based application. In particular, it does not work with Jersey <> -- [[production-ready-enabling]] == Enabling Production-ready Features The {github-code}/spring-boot-project/spring-boot-actuator[`spring-boot-actuator`] module provides all of Spring Boot's production-ready features. The simplest way to enable the features is to add a dependency to the `spring-boot-starter-actuator` '`Starter`'. .Definition of Actuator **** An actuator is a manufacturing term, referring to a mechanical device for moving or controlling something. Actuators can generate a large amount of motion from a small change. **** To add the actuator to a Maven based project, add the following '`Starter`' dependency: [source,xml,indent=0] ---- org.springframework.boot spring-boot-starter-actuator ---- For Gradle, use the following declaration: [source,groovy,indent=0] ---- dependencies { compile("org.springframework.boot:spring-boot-starter-actuator") } ---- [[production-ready-endpoints]] == Endpoints Actuator endpoints let you monitor and interact with your application. Spring Boot includes a number of built-in endpoints and lets you add your own. For example, the `health` endpoint provides basic application health information. The way that endpoints are exposed depends on the type of technology that you choose. Most applications choose HTTP monitoring, where the ID of the endpoint along with a prefix of `/application` is mapped to a URL. For example, by default, the `health` endpoint is mapped to `/application/health`. The following technology-agnostic endpoints are available: [cols="2,5"] |=== | ID | Description |`auditevents` |Exposes audit events information for the current application. |`conditions` |Showing the conditions that were evaluated on configuration and auto-configuration classes and the reasons why they did or did not match. |`beans` |Displays a complete list of all the Spring beans in your application. |`configprops` |Displays a collated list of all `@ConfigurationProperties`. |`env` |Exposes properties from Spring's `ConfigurableEnvironment`. |`flyway` |Shows any Flyway database migrations that have been applied. |`health` |Shows application health information. |`info` |Displays arbitrary application info. |`loggers` |Shows and modifies the configuration of loggers in the application. |`liquibase` |Shows any Liquibase database migrations that have been applied. |`metrics` |Shows '`metrics`' information for the current application. |`mappings` |Displays a collated list of all `@RequestMapping` paths. |`scheduledtasks` |Displays the scheduled tasks in your application. |`sessions` |Allows retrieval and deletion of user sessions from a Spring Session-backed session store. Not available when using Spring Session's support for reactive web applications. |`shutdown` |Lets the application be gracefully shutdown (not enabled by default). |`status` |Shows application status information (that is, `health` status with no additional details). |`threaddump` |Performs a thread dump. |`trace` |Displays trace information (by default, the last 100 HTTP requests). |=== If your application is a web application (Spring MVC, Spring WebFlux, or Jersey), you can use the following additional endpoints: [cols="2,5"] |=== | ID | Description |`heapdump` |Returns a GZip compressed `hprof` heap dump file. |`logfile` |Returns the contents of the logfile (if `logging.file` or `logging.path` properties have been set). Supports the use of the HTTP `Range` header to retrieve part of the log file's content. |`prometheus` |Exposes metrics in a format that can be scraped by a Prometheus server. |=== [[production-ready-endpoints-security]] === Securing Endpoints By default, all HTTP endpoints are secured such that only users that have an `ACTUATOR` role may access them. Security is enforced by using the standard `HttpServletRequest.isUserInRole` method. TIP: If you want to use something other than `ACTUATOR` as the role, set the `management.security.roles` property to the value you want to use. If you deploy applications behind a firewall, you may prefer that all your actuator endpoints can be accessed without requiring authentication. You can do so by changing the `management.security.enabled` property, as follows: .application.properties [source,properties,indent=0] ---- management.security.enabled=false ---- CAUTION: By default, actuator endpoints are exposed on the same port that serves regular HTTP traffic. Take care not to accidentally expose sensitive information if you change the `management.security.enabled` property. If you deploy applications publicly, you may want to add '`Spring Security`' to handle user authentication. When '`Spring Security`' is added, by default, '`basic`' authentication is used. The username is`user` and the password is a random generated password (which is printed on the console when the application starts). TIP: Generated passwords are logged as the application starts. To find the password in the console, search for '`Using default security password`'. You can use Spring properties to change the username and password and to change the security role(s) required to access the endpoints. For example, you might set the following properties in your `application.properties`: [source,properties,indent=0] ---- security.user.name=admin security.user.password=secret management.security.roles=SUPERUSER ---- If your application has custom security configuration and you want all your actuator endpoints to be accessible without authentication, you need to explicitly configure that in your security configuration. Also, you need to change the `management.security.enabled` property to `false`. If your custom security configuration secures your actuator endpoints, you also need to ensure that the authenticated user has the roles specified under `management.security.roles`. TIP: If you do not have a use case for exposing basic health information to unauthenticated users and you have secured the actuator endpoints with custom security, you can set `management.security.enabled` to `false`. This tells Spring Boot to skip the additional role check. [[production-ready-customizing-endpoints]] === Customizing Endpoints Endpoints can be customized by using Spring properties. You can change whether an endpoint is `enabled`. For example, the following `application.properties` enables the `shutdown` endpoint: [source,properties,indent=0] ---- endpoints.shutdown.enabled=true ---- NOTE: The prefix ‟`endpoints` + `.` + `id`” is used to uniquely identify the endpoint that is being configured. By default, all endpoints except for `shutdown` are enabled. If you prefer to specifically "`opt-in`" endpoint enablement, you can use the `endpoints.default.enabled` property. For example, the following settings disables _all_ endpoints except for `info`: [source,properties,indent=0] ---- endpoints.default.enabled=false endpoints.info.enabled=true ---- [[production-ready-endpoint-hypermedia]] === Hypermedia for Actuator Web Endpoints A "`discovery page`" is added with links to all the endpoints. The "`discovery page`" is available on `/application` by default. When a custom management context path is configured, the "`discovery page`" automatically moves from `/application` to the root of the management context. For example, if the management context path is `/management`, then the discovery page is available from `/management`. When the management context path is set to `/`, the discovery page is disabled to prevent the possibility of a clash with other mappings. [[production-ready-endpoint-cors]] === CORS Support http://en.wikipedia.org/wiki/Cross-origin_resource_sharing[Cross-origin resource sharing] (CORS) is a http://www.w3.org/TR/cors/[W3C specification] that allows you to specify in a flexible way what kind of cross domain requests are authorized. If you use Spring MVC or Spring WebFlux, Actuator's web endpoints can be configured to support such scenarios. CORS support is disabled by default and is only enabled once the `management.endpoints.cors.allowed-origins` property has been set. The following configuration permits `GET` and `POST` calls from the `example.com` domain: [source,properties,indent=0] ---- management.endpoints.cors.allowed-origins=http://example.com management.endpoints.cors.allowed-methods=GET,POST ---- TIP: See {sc-spring-boot-actuator-autoconfigure}/endpoint/web/servlet/CorsEndpointProperties.{sc-ext}[CorsEndpointProperties] for a complete list of options. [[production-ready-customizing-endpoints-programmatically]] === Adding Custom Endpoints If you add a `@Bean` annotated with `@Endpoint`, any methods annotated with `@ReadOperation` or `@WriteOperation` are automatically exposed over JMX and, in a web application, over HTTP as well. TIP: If you do this as a library feature, consider adding a configuration class annotated with `@ManagementContextConfiguration` to `/META-INF/spring.factories` under the key, `org.springframework.boot.actuate.autoconfigure.ManagementContextConfiguration`. If you do so and if your users ask for a separate management port or address, the endpoint moves to a child context with all the other web endpoints. [[production-ready-health]] === Health Information You can use health information to check the status of your running application. It is often used by monitoring software to alert someone when a production system goes down. The default information exposed by the `health` endpoint depends on how it is accessed. For an unauthenticated connection in a secure application, a simple '`status`' message is returned. For an authenticated connection, additional details are also displayed. (See <> for HTTP details.) Health information is collected from all {sc-spring-boot-actuator}/health/HealthIndicator.{sc-ext}[`HealthIndicator`] beans defined in your `ApplicationContext`. Spring Boot includes a number of auto-configured `HealthIndicators`, and you can also write your own. By default, the final system state is derived by the `HealthAggregator`, which sorts the statuses from each `HealthIndicator` based on an ordered list of statuses. The first status in the sorted list is used as the overall health status. If no `HealthIndicator` returns a status that is known to the `HealthAggregator`, an `UNKNOWN` status is used. ==== Auto-configured HealthIndicators The following `HealthIndicators` are auto-configured by Spring Boot when appropriate: [cols="1,4"] |=== |Name |Description |{sc-spring-boot-actuator}/cassandra/CassandraHealthIndicator.{sc-ext}[`CassandraHealthIndicator`] |Checks that a Cassandra database is up. |{sc-spring-boot-actuator}/system/DiskSpaceHealthIndicator.{sc-ext}[`DiskSpaceHealthIndicator`] |Checks for low disk space. |{sc-spring-boot-actuator}/jdbc/DataSourceHealthIndicator.{sc-ext}[`DataSourceHealthIndicator`] |Checks that a connection to `DataSource` can be obtained. |{sc-spring-boot-actuator}/elasticsearch/ElasticsearchHealthIndicator.{sc-ext}[`ElasticsearchHealthIndicator`] |Checks that an Elasticsearch cluster is up. |{sc-spring-boot-actuator}/jms/JmsHealthIndicator.{sc-ext}[`JmsHealthIndicator`] |Checks that a JMS broker is up. |{sc-spring-boot-actuator}/mail/MailHealthIndicator.{sc-ext}[`MailHealthIndicator`] |Checks that a mail server is up. |{sc-spring-boot-actuator}/mongo/MongoHealthIndicator.{sc-ext}[`MongoHealthIndicator`] |Checks that a Mongo database is up. |{sc-spring-boot-actuator}/amqp/RabbitHealthIndicator.{sc-ext}[`RabbitHealthIndicator`] |Checks that a Rabbit server is up. |{sc-spring-boot-actuator}/redis/RedisHealthIndicator.{sc-ext}[`RedisHealthIndicator`] |Checks that a Redis server is up. |{sc-spring-boot-actuator}/solr/SolrHealthIndicator.{sc-ext}[`SolrHealthIndicator`] |Checks that a Solr server is up. |=== TIP: It is possible to disable them all using the `management.health.defaults.enabled` property. ==== Writing Custom HealthIndicators To provide custom health information, you can register Spring beans that implement the {sc-spring-boot-actuator}/health/HealthIndicator.{sc-ext}[`HealthIndicator`] interface. You need to provide an implementation of the `health()` method and return a `Health` response. The `Health` response should include a status and can optionally include additional details to be displayed. The following code shows a sample `HealthIndicator` implementation: [source,java,indent=0] ---- import org.springframework.boot.actuate.health.Health; import org.springframework.boot.actuate.health.HealthIndicator; import org.springframework.stereotype.Component; @Component public class MyHealthIndicator implements HealthIndicator { @Override public Health health() { int errorCode = check(); // perform some specific health check if (errorCode != 0) { return Health.down().withDetail("Error Code", errorCode).build(); } return Health.up().build(); } } ---- NOTE: The identifier for a given `HealthIndicator` is the name of the bean without the `HealthIndicator` suffix, if it exists. In the preceding example, the health information is available in an entry named `my`. In addition to Spring Boot's predefined {sc-spring-boot-actuator}/health/Status.{sc-ext}[`Status`] types, it is also possible for `Health` to return a custom `Status` that represents a new system state. In such cases, a custom implementation of the {sc-spring-boot-actuator}/health/HealthAggregator.{sc-ext}[`HealthAggregator`] interface also needs to be provided, or the default implementation has to be configured by using the `management.health.status.order` configuration property. For example, assume a new `Status` with code `FATAL` is being used in one of your `HealthIndicator` implementations. To configure the severity order, add the following to your application properties: [source,properties,indent=0] ---- management.health.status.order=FATAL, DOWN, OUT_OF_SERVICE, UNKNOWN, UP ---- The HTTP status code in the response reflects the overall health status (for example, `UP` maps to 200, while `OUT_OF_SERVICE` and `DOWN` map to 503). You might also want to register custom status mappings if you access the health endpoint over HTTP. For example, the following property maps `FATAL` to 503 (service unavailable): [source,properties,indent=0] ---- management.health.status.http-mapping.FATAL=503 ---- TIP: If you need more control, you can define your own `HealthStatusHttpMapper` bean. The following table shows the default status mappings for the built-in statuses: [cols="1,3"] |=== |Status |Mapping |DOWN |SERVICE_UNAVAILABLE (503) |OUT_OF_SERVICE |SERVICE_UNAVAILABLE (503) |UP |No mapping by default, so http status is 200 |UNKNOWN |No mapping by default, so http status is 200 |=== [[production-ready-application-info]] === Application Information Application information exposes various information collected from all {sc-spring-boot-actuator}/info/InfoContributor.{sc-ext}[`InfoContributor`] beans defined in your `ApplicationContext`. Spring Boot includes a number of auto-configured `InfoContributors`, and you can write your own. [[production-ready-application-info-autoconfigure]] ==== Auto-configured InfoContributors The following `InfoContributors` are auto-configured by Spring Boot, when appropriate: [cols="1,4"] |=== |Name |Description |{sc-spring-boot-actuator}/info/EnvironmentInfoContributor.{sc-ext}[`EnvironmentInfoContributor`] |Expose any key from the `Environment` under the `info` key. |{sc-spring-boot-actuator}/info/GitInfoContributor.{sc-ext}[`GitInfoContributor`] |Expose git information if a `git.properties` file is available. |{sc-spring-boot-actuator}/info/BuildInfoContributor.{sc-ext}[`BuildInfoContributor`] |Expose build information if a `META-INF/build-info.properties` file is available. |=== TIP: It is possible to disable them all using the `management.info.defaults.enabled` property. [[production-ready-application-info-env]] ==== Custom Application Information You can customize the data exposed by the `info` endpoint by setting `+info.*+` Spring properties. All `Environment` properties under the info key are automatically exposed. For example, you could add the following settings to your `application.properties` file: [source,properties,indent=0] ---- info.app.encoding=UTF-8 info.app.java.source=1.8 info.app.java.target=1.8 ---- [TIP] ==== Rather than hardcoding those values, you could also <>. Assuming you use Maven, you could rewrite the preceding example as follows: [source,properties,indent=0] ---- info.app.encoding=@project.build.sourceEncoding@ info.app.java.source=@java.version@ info.app.java.target=@java.version@ ---- ==== [[production-ready-application-info-git]] ==== Git Commit Information Another useful feature of the `info` endpoint is its ability to publish information about the state of your `git` source code repository when the project was built. If a `GitProperties` bean is available, the `git.branch`, `git.commit.id` and `git.commit.time` properties are exposed. TIP: A `GitProperties` bean is auto-configured if a `git.properties` file is available at the root of the classpath. See "<>" for more details. If you want to display the full git information (that is, the full content of `git.properties`), use the `management.info.git.mode` property, as follows: [source,properties,indent=0] ---- management.info.git.mode=full ---- [[production-ready-application-info-build]] ==== Build Information If a `BuildProperties` bean is available, the `info` endpoint can also publish information about your build. This happens if a `META-INF/build-info.properties` file is available in the classpath. TIP: The Maven and Gradle plugins can both generate that file. See "<>" for more details. [[production-ready-application-info-custom]] ==== Writing Custom InfoContributors To provide custom application information, you can register Spring beans that implement the {sc-spring-boot-actuator}/info/InfoContributor.{sc-ext}[`InfoContributor`] interface. The following example contributes an `example` entry with a single value: [source,java,indent=0] ---- import java.util.Collections; import org.springframework.boot.actuate.info.Info; import org.springframework.boot.actuate.info.InfoContributor; import org.springframework.stereotype.Component; @Component public class ExampleInfoContributor implements InfoContributor { @Override public void contribute(Info.Builder builder) { builder.withDetail("example", Collections.singletonMap("key", "value")); } } ---- If you reach the `info` endpoint, you should see a response that contains the following additional entry: [source,json,indent=0] ---- { "example": { "key" : "value" } } ---- [[production-ready-monitoring]] == Monitoring and Management over HTTP If you are developing a Spring MVC application, Spring Boot Actuator auto-configures all enabled endpoints to be exposed over HTTP. The default convention is to use the `id` of the endpoint with a prefix of `/application` as the URL path. For example, `health` is exposed as `/application/health`. [[production-ready-customizing-management-server-context-path]] === Customizing the Management Endpoint Paths Sometimes, it is useful to customize the prefix for the management endpoints. For example, your application might already use `/application` for another purpose. You can use the `management.endpoints.web.base-path` property to change the prefix for your management endpoint, as shown in the following example: [source,properties,indent=0] ---- management.endpoints.web.base-path=/manage ---- The preceding `application.properties` example changes the endpoint from `/application/{id}` to `/manage/{id}` (e.g. `/manage/info`). NOTE: Unless the management port has been configured to <>, `management.endpoints.web.base-path` is relative to `server.context-path`. If `management.server.port` is configured, `management.endpoints.web.base-path` is relative to `management.server.servlet.context-path`. [[production-ready-customizing-management-server-port]] === Customizing the Management Server Port Exposing management endpoints by using the default HTTP port is a sensible choice for cloud based deployments. If, however, your application runs inside your own data center, you may prefer to expose endpoints by using a different HTTP port. You can set the `management.server.port` property to change the HTTP port, as shown in the following example: [source,properties,indent=0] ---- management.server.port=8081 ---- Since your management port is often protected by a firewall and not exposed to the public, you might not need security on the management endpoints, even if your main application is secure. In that case, you should have Spring Security on the classpath, and you can disable management security as follows: [source,properties,indent=0] ---- management.security.enabled=false ---- (If you do not have Spring Security on the classpath, there is no need to explicitly disable the management security in this way. Doing so might even break the application.) [[production-ready-management-specific-ssl]] === Configuring Management-specific SSL When configured to use a custom port, the management server can also be configured with its own SSL by using the various `management.server.ssl.*` properties. For example, doing so lets a management server be available via HTTP while the main application uses HTTPS, as shown in the following property settings: [source,properties,indent=0] ---- server.port=8443 server.ssl.enabled=true server.ssl.key-store=classpath:store.jks server.ssl.key-password=secret management.server.port=8080 management.server.ssl.enabled=false ---- Alternatively, both the main server and the management server can use SSL but with different key stores, as follows: [source,properties,indent=0] ---- server.port=8443 server.ssl.enabled=true server.ssl.key-store=classpath:main.jks server.ssl.key-password=secret management.server.port=8080 management.server.ssl.enabled=true management.server.ssl.key-store=classpath:management.jks management.server.ssl.key-password=secret ---- [[production-ready-customizing-management-server-address]] === Customizing the Management Server Address You can customize the address that the management endpoints are available on by setting the `management.server.address` property. Doing so can be useful if you want to listen only on an internal or ops-facing network or to listen only for connections from `localhost`. NOTE: You can only listen on a different address if the port is different from the main server port. The following example `application.properties` does not allow remote management connections: [source,properties,indent=0] ---- management.server.port=8081 management.server.address=127.0.0.1 ---- [[production-ready-disabling-http-endpoints]] === Disabling HTTP Endpoints If you do not want to expose endpoints over HTTP, you can set the management port to `-1`, as shown in the following example: [source,properties,indent=0] ---- management.server.port=-1 ---- [[production-ready-health-access-restrictions]] === HTTP Health Endpoint Format and Access Restrictions The information exposed by the health endpoint varies, depending on whether it is accessed anonymously and whether the enclosing application is secure. By default, when accessed anonymously in a secure application, any details about the server's health are hidden and the endpoint indicates whether the server is up or down. The following example shows a summarized HTTP response (default for anonymous request): [source,indent=0] ---- $ curl -i localhost:8080/health HTTP/1.1 200 X-Application-Context: application Content-Type: application/vnd.spring-boot.actuator.v2+json;charset=UTF-8 Content-Length: 15 {"status":"UP"} ---- The following example shows a summarized HTTP response for status "DOWN" (notice the 503 status code): [source,indent=0] ---- $ curl -i localhost:8080/health HTTP/1.1 503 X-Application-Context: application Content-Type: application/vnd.spring-boot.actuator.v2+json;charset=UTF-8 Content-Length: 17 {"status":"DOWN"} ---- The following example shows a detailed HTTP response: [source,indent=0] ---- $ curl -i localhost:8080/health HTTP/1.1 200 OK X-Application-Context: application Content-Type: application/vnd.spring-boot.actuator.v2+json;charset=UTF-8 Content-Length: 221 { "status" : "UP", "diskSpace" : { "status" : "UP", "total" : 63251804160, "free" : 31316164608, "threshold" : 10485760 }, "db" : { "status" : "UP", "database" : "H2", "hello" : 1 } } ---- [[production-ready-jmx]] == Monitoring and Management over JMX Java Management Extensions (JMX) provide a standard mechanism to monitor and manage applications. By default, Spring Boot exposes management endpoints as JMX MBeans under the `org.springframework.boot` domain. [[production-ready-custom-mbean-names]] === Customizing MBean Names The name of the MBean is usually generated from the `id` of the endpoint. For example the `health` endpoint is exposed as `org.springframework.boot:type=Endpoint,name=Health`. If your application contains more than one Spring `ApplicationContext`, you may find that names clash. To solve this problem, you can set the `management.endpoints.jmx.unique-names` property to `true` so that MBean names are always unique. You can also customize the JMX domain under which endpoints are exposed. The following settings show an example of doing so in `application.properties`: [source,properties,indent=0] ---- management.endpoints.jmx.domain=com.example.myapp management.endpoints.jmx.unique-names=true ---- [[production-ready-disable-jmx-endpoints]] === Disabling JMX Endpoints If you do not want to expose endpoints over JMX, you can set the `endpoints.default.jmx.enabled` property to `false`, as shown in the following example: [source,properties,indent=0] ---- endpoints.default.jmx.enabled=false ---- [[production-ready-jolokia]] === Using Jolokia for JMX over HTTP Jolokia is a JMX-HTTP bridge that provides an alternative method of accessing JMX beans. To use Jolokia, include a dependency to `org.jolokia:jolokia-core`. For example, with Maven, you would add the following dependency: [source,xml,indent=0] ---- org.jolokia jolokia-core ---- Jolokia can then be accessed by using `/application/jolokia` on your management HTTP server. [[production-ready-customizing-jolokia]] ==== Customizing Jolokia Jolokia has a number of settings that you would traditionally configure using servlet parameters. With Spring Boot, you can use your `application.properties`. Prefix the parameter with `management.jolokia.config.`, as shown in the following example: [source,properties,indent=0] ---- management.jolokia.config.debug=true ---- [[production-ready-disabling-jolokia]] ==== Disabling Jolokia If you use Jolokia but do not want Spring Boot to configure it, set the `management.jolokia.enabled` property to `false`, as follows: [source,properties,indent=0] ---- management.jolokia.enabled=false ---- [[production-ready-loggers]] == Loggers Spring Boot Actuator includes the ability to view and configure the log levels of your application at runtime. You can view either the entire list or an individual logger's configuration, which is made up of both the explicitly configured logging level as well as the effective logging level given to it by the logging framework. These levels can be one of: * `TRACE` * `DEBUG` * `INFO` * `WARN` * `ERROR` * `FATAL` * `OFF` * `null` `null` indicates that there is no explicit configuration. [[production-ready-logger-configuration]] === Configure a Logger In order to configure a given logger, you `POST` a partial entity to the resource's URI, as shown in the following example: [source,json,indent=0] ---- { "configuredLevel": "DEBUG" } ---- TIP: To "reset" the specific level of the logger (and use the default configuration instead), you can pass a value of `null` as the `configuredLevel`. [[production-ready-metrics]] == Metrics Spring Boot Actuator provides dependency management and auto-configuration for https://micrometer.io[Micrometer], an application metrics facade that supports numerous monitoring systems: - https://github.com/Netflix/atlas[Atlas] - https://www.datadoghq.com[Datadog] - http://ganglia.sourceforge.net[Ganglia] - https://graphiteapp.org[Graphite] - https://www.influxdata.com[Influx] - https://prometheus.io[Prometheus] Micrometer provides a separate module for each supported monitoring system. Depending on one (or more) of these modules is sufficient to get started with Micrometer in your Spring Boot application. To learn more about Micrometer's capabilities, please refer to its https://micrometer.io/docs[reference documentation]. [[production-ready-metrics-spring-mvc]] === Spring MVC Metrics Auto-configuration enables the instrumentation of requests handled by Spring MVC. When `spring.metrics.web.server.auto-time-requests` is `true`, this instrumentation occurs for all requests. Alternatively, when set to `false`, you can enable instrumentation by adding `@Timed` to a request-handling method. By default, metrics are generated with the name, `http.server.requests`. The name can be customized by setting the `spring.metrics.web.server.requests-metrics-name` property. [[production-ready-metrics-spring-mvc-tags]] ==== Spring MVC Metric Tags By default, Spring MVC-related metrics are tagged with the following information: - The request's method. - The request's URI (templated if possible). - The simple class name of any exception that was thrown while handling the request. - The response's status. To customize the tags, provide a `@Bean` that implements `WebMvcTagsProvider`. [[production-ready-metrics-web-flux]] === WebFlux Metrics Auto-configuration enables the instrumentation of all requests handled by WebFlux controllers. You can also use a helper class, `RouterFunctionMetrics`, to instrument applications that use WebFlux's functional programming model. By default, metrics are generated with the name `http.server.requests`. You can customize the name by setting the `spring.metrics.web.server.requests-metrics-name` property. [[production-ready-metrics-web-flux-tags]] ==== WebFlux Metric Tags By default, WebFlux-related metrics for the annotation-based programming model are tagged with the following information: - The request's method. - The request's URI (templated if possible). - The simple class name of any exception that was thrown while handling the request. - The response's status. To customize the tags, provide a `@Bean` that implements `WebFluxTagsProvider`. By default, metrics for the functional programming model are tagged with the following information: - The request's method - The request's URI (templated if possible). - The response's status. To customize the tags, use the `defaultTags` method on your `RouterFunctionMetrics` instance. [[production-ready-metrics-rest-template]] === RestTemplate Metrics Auto-configuration customizes the auto-configured `RestTemplate` to enable the instrumentation of its requests. `MetricsRestTemplateCustomizer` can be used to customize your own `RestTemplate` instances. By default, metrics are generated with the name, `http.client.requests`. The name can be customized by setting the `spring.metrics.web.client.requests-metrics-name` property. [[production-ready-metrics-rest-template-tags]] ==== RestTemplate Metric Tags By default, metrics generated by an instrumented `RestTemplate` are tagged with the following information: - The request's method. - The request's URI (templated if possible). - The response's status. - The request URI's host. [[production-ready-metrics-jdbc]] === DataSource metrics Auto-configuration will enable the instrumentation of all available `DataSources` with a metric named `data.source`. Data source instrumentation results in gauges representing the currently active, maximum allowed, and minimum allowed connections in the pool. Each of these gauges has a name which is prefixed by `data.source` by default. The prefix can be customized by using the `spring.metrics.jdbc.datasource-metric-name` property. Metrics will also be tagged by the name of the `DataSource` computed based on the bean name. [[production-ready-metrics-integration]] === Spring Integration Metrics Auto-configuration enables binding of a number of Spring Integration-related metrics: .General metrics |=== | Metric | Description | `spring.integration.channelNames` | Number of Spring Integration channels | `spring.integration.handlerNames` | Number of Spring Integration handlers | `spring.integration.sourceNames` | Number of Spring Integration sources |=== .Channel metrics |=== | Metric | Description | `spring.integration.channel.receives` | Number of receives | `spring.integration.channel.sendErrors` | Number of failed sends | `spring.integration.channel.sends` | Number of successful sends |=== .Handler metrics |=== | Metric | Description | `spring.integration.handler.duration.max` | Maximum handler duration in milliseconds | `spring.integration.handler.duration.min` | Minimum handler duration in milliseconds | `spring.integration.handler.duration.mean` | Mean handler duration in milliseconds | `spring.integration.handler.activeCount` | Number of active handlers |=== .Source metrics |=== | Metric | Description | `spring.integration.source.messages` | Number of successful source calls |=== [[production-ready-auditing]] == Auditing Once Spring Security is in play Spring Boot Actuator has a flexible audit framework that publishes events (by default, '`authentication success`', '`failure`' and '`access denied`' exceptions). This feature can be very useful for reporting and for implementing a lock-out policy based on authentication failures. To customize published security events, you can provide your own implementations of `AbstractAuthenticationAuditListener` and `AbstractAuthorizationAuditListener`. You can also use the audit services for your own business events. To do so, either inject the existing `AuditEventRepository` into your own components and use that directly or publish an `AuditApplicationEvent` with the Spring `ApplicationEventPublisher` (by implementing `ApplicationEventPublisherAware`). [[production-ready-tracing]] == Tracing Tracing is automatically enabled for all HTTP requests. You can view the `trace` endpoint and obtain basic information about the last 100 requests. The following listing shows sample output: [source,json,indent=0] ---- [{ "timestamp": 1394343677415, "info": { "method": "GET", "path": "/trace", "headers": { "request": { "Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8", "Connection": "keep-alive", "Accept-Encoding": "gzip, deflate", "User-Agent": "Mozilla/5.0 Gecko/Firefox", "Accept-Language": "en-US,en;q=0.5", "Cookie": "_ga=GA1.1.827067509.1390890128; ..." "Authorization": "Basic ...", "Host": "localhost:8080" }, "response": { "Strict-Transport-Security": "max-age=31536000 ; includeSubDomains", "X-Application-Context": "application:8080", "Content-Type": "application/json;charset=UTF-8", "status": "200" } } } },{ "timestamp": 1394343684465, ... }] ---- By default, the trace includes the following information: [cols="1,2"] |=== |Name |Description |Request Headers |Headers from the request. |Response Headers |Headers from the response. |Cookies |`Cookie` from request headers and `Set-Cookie` from response headers. |Errors |The error attributes (if any). |Time Taken |The time taken to service the request in milliseconds. |=== [[production-ready-custom-tracing]] === Custom tracing If you need to trace additional events, you can inject a {sc-spring-boot-actuator}/trace/TraceRepository.{sc-ext}[`TraceRepository`] into your Spring beans. The `add` method accepts a single `Map` structure that is converted to JSON and logged. By default, an `InMemoryTraceRepository` that stores the last 100 events is used. If you need to expand the capacity, you can define your own instance of the `InMemoryTraceRepository` bean. You can also create your own alternative `TraceRepository` implementation. [[production-ready-process-monitoring]] == Process Monitoring In the `spring-boot` module, you can find two classes to create files that are often useful for process monitoring: * `ApplicationPidFileWriter` creates a file containing the application PID (by default, in the application directory with the file name, `application.pid`). * `EmbeddedServerPortFileWriter` creates a file (or files) containing the ports of the embedded server (by default, in the application directory with the file name `application.port`). By default, these writers are not activated, but you can enable them in one of the ways described in the next section. [[production-ready-process-monitoring-configuration]] === Extend Configuration In the `META-INF/spring.factories` file, you can activate the listener(s) that writes a PID file, as shown in the following example: [indent=0] ---- org.springframework.context.ApplicationListener=\ org.springframework.boot.system.ApplicationPidFileWriter,\ org.springframework.boot.system.EmbeddedServerPortFileWriter ---- [[production-ready-process-monitoring-programmatically]] === Programmatically You can also activate a listener by invoking the `SpringApplication.addListeners(...)` method and passing the appropriate `Writer` object. This method also lets you customize the file name and path in the `Writer` constructor. [[production-ready-cloudfoundry]] == Cloud Foundry Support Spring Boot's actuator module includes additional support that is activated when you deploy to a compatible Cloud Foundry instance. The `/cloudfoundryapplication` path provides an alternative secured route to all `@Endpoint` beans. The extended support lets Cloud Foundry management UIs (such as the web application that you can use to view deployed applications) be augmented with Spring Boot actuator information. For example, an application status page may include full health information instead of the typical "`running`" or "`stopped`" status. NOTE: The `/cloudfoundryapplication` path is not directly accessible to regular users. In order to use the endpoint, a valid UAA token must be passed with the request. [[production-ready-cloudfoundry-disable]] === Disabling Extended Cloud Foundry Actuator Support If you want to fully disable the `/cloudfoundryapplication` endpoints, you can add the following setting to your `application.properties` file: .application.properties [source,properties,indent=0] ---- management.cloudfoundry.enabled=false ---- [[production-ready-cloudfoundry-ssl]] === Cloud Foundry Self-signed Certificates By default, the security verification for `/cloudfoundryapplication` endpoints makes SSL calls to various Cloud Foundry services. If your Cloud Foundry UAA or Cloud Controller services use self-signed certificates, you need to set the following property: .application.properties [source,properties,indent=0] ---- management.cloudfoundry.skip-ssl-validation=true ---- [[production-ready-cloudfoundry-custom-security]] === Custom Security Configuration If you define custom security configuration and you want extended Cloud Foundry actuator support, you should ensure that `/cloudfoundryapplication/**` paths are open. Without a direct open route, your Cloud Foundry application manager is not able to obtain endpoint data. For Spring Security, you typically include something like `mvcMatchers("/cloudfoundryapplication/**").permitAll()` in your configuration, as shown in the following example: [source,java,indent=0] ---- include::{code-examples}/cloudfoundry/CloudFoundryIgnorePathsExample.java[tag=security] ---- [[production-ready-whats-next]] == What to Read Next If you want to explore some of the concepts discussed in this chapter, you can take a look at the actuator {github-code}/spring-boot-samples[sample applications]. You also might want to read about graphing tools such as http://graphite.wikidot.com/[Graphite]. Otherwise, you can continue on, to read about <> or jump ahead for some in-depth information about Spring Boot's _<>_.