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.
1. Enabling Production-ready Features
The spring-boot-actuator
module provides all of Spring Boot’s production-ready features.
The recommended way to enable the features is to add a dependency on the spring-boot-starter-actuator
“Starter”.
To add the actuator to a Maven-based project, add the following “Starter” dependency:
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
</dependencies>
For Gradle, use the following declaration:
dependencies {
implementation 'org.springframework.boot:spring-boot-starter-actuator'
}
2. 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.
You can enable or disable each individual endpoint and expose them (make them remotely accessible) over HTTP or JMX.
An endpoint is considered to be available when it is both enabled and exposed.
The built-in endpoints are auto-configured only when they are available.
Most applications choose exposure over HTTP, where the ID of the endpoint and a prefix of /actuator
is mapped to a URL.
For example, by default, the health
endpoint is mapped to /actuator/health
.
To learn more about the Actuator’s endpoints and their request and response formats, see the separate API documentation (HTML or PDF). |
The following technology-agnostic endpoints are available:
ID | Description |
---|---|
|
Exposes audit events information for the current application.
Requires an |
|
Displays a complete list of all the Spring beans in your application. |
|
Exposes available caches. |
|
Shows the conditions that were evaluated on configuration and auto-configuration classes and the reasons why they did or did not match. |
|
Displays a collated list of all |
|
Exposes properties from Spring’s |
|
Shows any Flyway database migrations that have been applied.
Requires one or more |
|
Shows application health information. |
|
Displays HTTP exchange information (by default, the last 100 HTTP request-response exchanges).
Requires an |
|
Displays arbitrary application info. |
|
Shows the Spring Integration graph.
Requires a dependency on |
|
Shows and modifies the configuration of loggers in the application. |
|
Shows any Liquibase database migrations that have been applied.
Requires one or more |
|
Shows “metrics” information for the current application. |
|
Displays a collated list of all |
|
Shows information about Quartz Scheduler jobs. Subject to sanitization. |
|
Displays the scheduled tasks in your application. |
|
Allows retrieval and deletion of user sessions from a Spring Session-backed session store. Requires a servlet-based web application that uses Spring Session. |
|
Lets the application be gracefully shutdown. Only works when using jar packaging. Disabled by default. |
|
Shows the startup steps data collected by the |
|
Performs a thread dump. |
If your application is a web application (Spring MVC, Spring WebFlux, or Jersey), you can use the following additional endpoints:
ID | Description |
---|---|
|
Returns a heap dump file.
On a HotSpot JVM, an |
|
Returns the contents of the logfile (if the |
|
Exposes metrics in a format that can be scraped by a Prometheus server.
Requires a dependency on |
2.1. Enabling Endpoints
By default, all endpoints except for shutdown
are enabled.
To configure the enablement of an endpoint, use its management.endpoint.<id>.enabled
property.
The following example enables the shutdown
endpoint:
management.endpoint.shutdown.enabled=true
management:
endpoint:
shutdown:
enabled: true
If you prefer endpoint enablement to be opt-in rather than opt-out, set the management.endpoints.enabled-by-default
property to false
and use individual endpoint enabled
properties to opt back in.
The following example enables the info
endpoint and disables all other endpoints:
management.endpoints.enabled-by-default=false
management.endpoint.info.enabled=true
management:
endpoints:
enabled-by-default: false
endpoint:
info:
enabled: true
Disabled endpoints are removed entirely from the application context.
If you want to change only the technologies over which an endpoint is exposed, use the include and exclude properties instead.
|
2.2. Exposing Endpoints
By default, only the health endpoint is exposed over HTTP and JMX. Since Endpoints may contain sensitive information, you should carefully consider when to expose them.
To change which endpoints are exposed, use the following technology-specific include
and exclude
properties:
Property | Default |
---|---|
|
|
|
|
|
|
|
|
The include
property lists the IDs of the endpoints that are exposed.
The exclude
property lists the IDs of the endpoints that should not be exposed.
The exclude
property takes precedence over the include
property.
You can configure both the include
and the exclude
properties with a list of endpoint IDs.
For example, to only expose the health
and info
endpoints over JMX, use the following property:
management.endpoints.jmx.exposure.include=health,info
management:
endpoints:
jmx:
exposure:
include: "health,info"
*
can be used to select all endpoints.
For example, to expose everything over HTTP except the env
and beans
endpoints, use the following properties:
management.endpoints.web.exposure.include=*
management.endpoints.web.exposure.exclude=env,beans
management:
endpoints:
web:
exposure:
include: "*"
exclude: "env,beans"
* has a special meaning in YAML, so be sure to add quotation marks if you want to include (or exclude) all endpoints.
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If your application is exposed publicly, we strongly recommend that you also secure your endpoints. |
If you want to implement your own strategy for when endpoints are exposed, you can register an EndpointFilter bean.
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2.3. Security
For security purposes, only the /health
endpoint is exposed over HTTP by default.
You can use the management.endpoints.web.exposure.include
property to configure the endpoints that are exposed.
Before setting the management.endpoints.web.exposure.include , ensure that the exposed actuators do not contain sensitive information, are secured by placing them behind a firewall, or are secured by something like Spring Security.
|
If Spring Security is on the classpath and no other SecurityFilterChain
bean is present, all actuators other than /health
are secured by Spring Boot auto-configuration.
If you define a custom SecurityFilterChain
bean, Spring Boot auto-configuration backs off and lets you fully control the actuator access rules.
If you wish to configure custom security for HTTP endpoints (for example, to allow only users with a certain role to access them), Spring Boot provides some convenient RequestMatcher
objects that you can use in combination with Spring Security.
A typical Spring Security configuration might look something like the following example:
@Configuration(proxyBeanMethods = false)
public class MySecurityConfiguration {
@Bean
public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
http.securityMatcher(EndpointRequest.toAnyEndpoint());
http.authorizeHttpRequests((requests) -> requests.anyRequest().hasRole("ENDPOINT_ADMIN"));
http.httpBasic(withDefaults());
return http.build();
}
}
@Configuration(proxyBeanMethods = false)
class MySecurityConfiguration {
@Bean
fun securityFilterChain(http: HttpSecurity): SecurityFilterChain {
http.securityMatcher(EndpointRequest.toAnyEndpoint()).authorizeHttpRequests { requests ->
requests.anyRequest().hasRole("ENDPOINT_ADMIN")
}
http.httpBasic(withDefaults())
return http.build()
}
}
The preceding example uses EndpointRequest.toAnyEndpoint()
to match a request to any endpoint and then ensures that all have the ENDPOINT_ADMIN
role.
Several other matcher methods are also available on EndpointRequest
.
See the API documentation (HTML or PDF) for details.
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.endpoints.web.exposure.include
property, as follows:
management.endpoints.web.exposure.include=*
management:
endpoints:
web:
exposure:
include: "*"
Additionally, if Spring Security is present, you would need to add custom security configuration that allows unauthenticated access to the endpoints, as the following example shows:
@Configuration(proxyBeanMethods = false)
public class MySecurityConfiguration {
@Bean
public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
http.securityMatcher(EndpointRequest.toAnyEndpoint());
http.authorizeHttpRequests((requests) -> requests.anyRequest().permitAll());
return http.build();
}
}
@Configuration(proxyBeanMethods = false)
class MySecurityConfiguration {
@Bean
fun securityFilterChain(http: HttpSecurity): SecurityFilterChain {
http.securityMatcher(EndpointRequest.toAnyEndpoint()).authorizeHttpRequests { requests ->
requests.anyRequest().permitAll()
}
return http.build()
}
}
In both of the preceding examples, the configuration applies only to the actuator endpoints.
Since Spring Boot’s security configuration backs off completely in the presence of any SecurityFilterChain bean, you need to configure an additional SecurityFilterChain bean with rules that apply to the rest of the application.
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2.3.1. Cross Site Request Forgery Protection
Since Spring Boot relies on Spring Security’s defaults, CSRF protection is turned on by default.
This means that the actuator endpoints that require a POST
(shutdown and loggers endpoints), a PUT
, or a DELETE
get a 403 (forbidden) error when the default security configuration is in use.
We recommend disabling CSRF protection completely only if you are creating a service that is used by non-browser clients. |
You can find additional information about CSRF protection in the Spring Security Reference Guide.
2.4. Configuring Endpoints
Endpoints automatically cache responses to read operations that do not take any parameters.
To configure the amount of time for which an endpoint caches a response, use its cache.time-to-live
property.
The following example sets the time-to-live of the beans
endpoint’s cache to 10 seconds:
management.endpoint.beans.cache.time-to-live=10s
management:
endpoint:
beans:
cache:
time-to-live: "10s"
The management.endpoint.<name> prefix uniquely identifies the endpoint that is being configured.
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2.5. Sanitize Sensitive Values
Information returned by the /env
, /configprops
and /quartz
endpoints can be somewhat sensitive.
All values are sanitized by default (that is replaced by ******
).
Viewing original values in the unsanitized form can be configured per endpoint using the showValues
property for that endpoint.
This property can be configured to have the following values:
-
ALWAYS
- all values are shown in their unsanitized form to all users -
NEVER
- all values are always sanitized (that is replaced by******
) -
WHEN_AUTHORIZED
- all values are shown in their unsanitized form to authorized users
For HTTP endpoints, a user is considered to be authorized if they have authenticated and have the roles configured by the endpoint’s roles property. By default, any authenticated user is authorized. For JMX endpoints, all users are always authorized.
management.endpoint.env.show-values=WHEN_AUTHORIZED
management.endpoint.env.roles=admin
management:
endpoint:
env:
show-values: WHEN_AUTHORIZED
roles: "admin"
The configuration above enables the ability for all users with the admin
role to view all values in their original form from the /env
endpoint.
When show-values is set to ALWAYS or WHEN_AUTHORIZED any sanitization applied by a SanitizingFunction will still be applied.
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2.6. Hypermedia for Actuator Web Endpoints
A “discovery page” is added with links to all the endpoints.
The “discovery page” is available on /actuator
by default.
To disable the “discovery page”, add the following property to your application properties:
management.endpoints.web.discovery.enabled=false
management:
endpoints:
web:
discovery:
enabled: false
When a custom management context path is configured, the “discovery page” automatically moves from /actuator
to the root of the management context.
For example, if the management context path is /management
, 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.
2.7. CORS Support
Cross-origin resource sharing (CORS) is a W3C specification that lets you specify in a flexible way what kind of cross-domain requests are authorized. If you use Spring MVC or Spring WebFlux, you can configure Actuator’s web endpoints to support such scenarios.
CORS support is disabled by default and is only enabled once you have set the management.endpoints.web.cors.allowed-origins
property.
The following configuration permits GET
and POST
calls from the example.com
domain:
management.endpoints.web.cors.allowed-origins=https://example.com
management.endpoints.web.cors.allowed-methods=GET,POST
management:
endpoints:
web:
cors:
allowed-origins: "https://example.com"
allowed-methods: "GET,POST"
See CorsEndpointProperties for a complete list of options.
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2.8. Implementing Custom Endpoints
If you add a @Bean
annotated with @Endpoint
, any methods annotated with @ReadOperation
, @WriteOperation
, or @DeleteOperation
are automatically exposed over JMX and, in a web application, over HTTP as well.
Endpoints can be exposed over HTTP by using Jersey, Spring MVC, or Spring WebFlux.
If both Jersey and Spring MVC are available, Spring MVC is used.
The following example exposes a read operation that returns a custom object:
@ReadOperation
public CustomData getData() {
return new CustomData("test", 5);
}
@ReadOperation
fun getData(): CustomData {
return CustomData("test", 5)
}
You can also write technology-specific endpoints by using @JmxEndpoint
or @WebEndpoint
.
These endpoints are restricted to their respective technologies.
For example, @WebEndpoint
is exposed only over HTTP and not over JMX.
You can write technology-specific extensions by using @EndpointWebExtension
and @EndpointJmxExtension
.
These annotations let you provide technology-specific operations to augment an existing endpoint.
Finally, if you need access to web-framework-specific functionality, you can implement servlet or Spring @Controller
and @RestController
endpoints at the cost of them not being available over JMX or when using a different web framework.
2.8.1. Receiving Input
Operations on an endpoint receive input through their parameters.
When exposed over the web, the values for these parameters are taken from the URL’s query parameters and from the JSON request body.
When exposed over JMX, the parameters are mapped to the parameters of the MBean’s operations.
Parameters are required by default.
They can be made optional by annotating them with either @javax.annotation.Nullable
or @org.springframework.lang.Nullable
.
You can map each root property in the JSON request body to a parameter of the endpoint. Consider the following JSON request body:
{
"name": "test",
"counter": 42
}
You can use this to invoke a write operation that takes String name
and int counter
parameters, as the following example shows:
@WriteOperation
public void updateData(String name, int counter) {
// injects "test" and 42
}
@WriteOperation
fun updateData(name: String?, counter: Int) {
// injects "test" and 42
}
Because endpoints are technology agnostic, only simple types can be specified in the method signature.
In particular, declaring a single parameter with a CustomData type that defines a name and counter properties is not supported.
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To let the input be mapped to the operation method’s parameters, Java code that implements an endpoint should be compiled with -parameters , and Kotlin code that implements an endpoint should be compiled with -java-parameters .
This will happen automatically if you use Spring Boot’s Gradle plugin or if you use Maven and spring-boot-starter-parent .
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Input Type Conversion
The parameters passed to endpoint operation methods are, if necessary, automatically converted to the required type.
Before calling an operation method, the input received over JMX or HTTP is converted to the required types by using an instance of ApplicationConversionService
as well as any Converter
or GenericConverter
beans qualified with @EndpointConverter
.
2.8.2. Custom Web Endpoints
Operations on an @Endpoint
, @WebEndpoint
, or @EndpointWebExtension
are automatically exposed over HTTP using Jersey, Spring MVC, or Spring WebFlux.
If both Jersey and Spring MVC are available, Spring MVC is used.
Web Endpoint Request Predicates
A request predicate is automatically generated for each operation on a web-exposed endpoint.
Path
The path of the predicate is determined by the ID of the endpoint and the base path of the web-exposed endpoints.
The default base path is /actuator
.
For example, an endpoint with an ID of sessions
uses /actuator/sessions
as its path in the predicate.
You can further customize the path by annotating one or more parameters of the operation method with @Selector
.
Such a parameter is added to the path predicate as a path variable.
The variable’s value is passed into the operation method when the endpoint operation is invoked.
If you want to capture all remaining path elements, you can add @Selector(Match=ALL_REMAINING)
to the last parameter and make it a type that is conversion-compatible with a String[]
.
HTTP method
The HTTP method of the predicate is determined by the operation type, as shown in the following table:
Operation | HTTP method |
---|---|
|
|
|
|
|
|
Consumes
For a @WriteOperation
(HTTP POST
) that uses the request body, the consumes
clause of the predicate is application/vnd.spring-boot.actuator.v2+json, application/json
.
For all other operations, the consumes
clause is empty.
Produces
The produces
clause of the predicate can be determined by the produces
attribute of the @DeleteOperation
, @ReadOperation
, and @WriteOperation
annotations.
The attribute is optional.
If it is not used, the produces
clause is determined automatically.
If the operation method returns void
or Void
, the produces
clause is empty.
If the operation method returns a org.springframework.core.io.Resource
, the produces
clause is application/octet-stream
.
For all other operations, the produces
clause is application/vnd.spring-boot.actuator.v2+json, application/json
.
Web Endpoint Response Status
The default response status for an endpoint operation depends on the operation type (read, write, or delete) and what, if anything, the operation returns.
If a @ReadOperation
returns a value, the response status will be 200 (OK).
If it does not return a value, the response status will be 404 (Not Found).
If a @WriteOperation
or @DeleteOperation
returns a value, the response status will be 200 (OK).
If it does not return a value, the response status will be 204 (No Content).
If an operation is invoked without a required parameter or with a parameter that cannot be converted to the required type, the operation method is not called, and the response status will be 400 (Bad Request).
Web Endpoint Range Requests
You can use an HTTP range request to request part of an HTTP resource.
When using Spring MVC or Spring Web Flux, operations that return a org.springframework.core.io.Resource
automatically support range requests.
Range requests are not supported when using Jersey. |
Web Endpoint Security
An operation on a web endpoint or a web-specific endpoint extension can receive the current java.security.Principal
or org.springframework.boot.actuate.endpoint.SecurityContext
as a method parameter.
The former is typically used in conjunction with @Nullable
to provide different behavior for authenticated and unauthenticated users.
The latter is typically used to perform authorization checks by using its isUserInRole(String)
method.
2.8.3. Servlet Endpoints
A servlet can be exposed as an endpoint by implementing a class annotated with @ServletEndpoint
that also implements Supplier<EndpointServlet>
.
Servlet endpoints provide deeper integration with the servlet container but at the expense of portability.
They are intended to be used to expose an existing servlet as an endpoint.
For new endpoints, the @Endpoint
and @WebEndpoint
annotations should be preferred whenever possible.
2.8.4. Controller Endpoints
You can use @ControllerEndpoint
and @RestControllerEndpoint
to implement an endpoint that is exposed only by Spring MVC or Spring WebFlux.
Methods are mapped by using the standard annotations for Spring MVC and Spring WebFlux, such as @RequestMapping
and @GetMapping
, with the endpoint’s ID being used as a prefix for the path.
Controller endpoints provide deeper integration with Spring’s web frameworks but at the expense of portability.
The @Endpoint
and @WebEndpoint
annotations should be preferred whenever possible.
2.9. 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 information exposed by the health
endpoint depends on the management.endpoint.health.show-details
and management.endpoint.health.show-components
properties, which can be configured with one of the following values:
Name | Description |
---|---|
|
Details are never shown. |
|
Details are shown only to authorized users.
Authorized roles can be configured by using |
|
Details are shown to all users. |
The default value is never
.
A user is considered to be authorized when they are in one or more of the endpoint’s roles.
If the endpoint has no configured roles (the default), all authenticated users are considered to be authorized.
You can configure the roles by using the management.endpoint.health.roles
property.
If you have secured your application and wish to use always , your security configuration must permit access to the health endpoint for both authenticated and unauthenticated users.
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Health information is collected from the content of a HealthContributorRegistry
(by default, all HealthContributor
instances defined in your ApplicationContext
).
Spring Boot includes a number of auto-configured HealthContributors
, and you can also write your own.
A HealthContributor
can be either a HealthIndicator
or a CompositeHealthContributor
.
A HealthIndicator
provides actual health information, including a Status
.
A CompositeHealthContributor
provides a composite of other HealthContributors
.
Taken together, contributors form a tree structure to represent the overall system health.
By default, the final system health is derived by a StatusAggregator
, 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 StatusAggregator
, an UNKNOWN
status is used.
You can use the HealthContributorRegistry to register and unregister health indicators at runtime.
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2.9.1. Auto-configured HealthIndicators
When appropriate, Spring Boot auto-configures the HealthIndicators
listed in the following table.
You can also enable or disable selected indicators by configuring management.health.key.enabled
,
with the key
listed in the following table:
Key | Name | Description |
---|---|---|
|
Checks that a Cassandra database is up. |
|
|
Checks that a Couchbase cluster is up. |
|
|
Checks that a connection to |
|
|
Checks for low disk space. |
|
|
Checks that an Elasticsearch cluster is up. |
|
|
Checks that a Hazelcast server is up. |
|
|
Checks that an InfluxDB server is up. |
|
|
Checks that a JMS broker is up. |
|
|
Checks that an LDAP server is up. |
|
|
Checks that a mail server is up. |
|
|
Checks that a Mongo database is up. |
|
|
Checks that a Neo4j database is up. |
|
|
Always responds with |
|
|
Checks that a Rabbit server is up. |
|
|
Checks that a Redis server is up. |
You can disable them all by setting the management.health.defaults.enabled property.
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Additional HealthIndicators
are available but are not enabled by default:
Key | Name | Description |
---|---|---|
|
Exposes the “Liveness” application availability state. |
|
|
Exposes the “Readiness” application availability state. |
2.9.2. Writing Custom HealthIndicators
To provide custom health information, you can register Spring beans that implement the 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:
@Component
public class MyHealthIndicator implements HealthIndicator {
@Override
public Health health() {
int errorCode = check();
if (errorCode != 0) {
return Health.down().withDetail("Error Code", errorCode).build();
}
return Health.up().build();
}
private int check() {
// perform some specific health check
return ...
}
}
@Component
class MyHealthIndicator : HealthIndicator {
override fun health(): Health {
val errorCode = check()
if (errorCode != 0) {
return Health.down().withDetail("Error Code", errorCode).build()
}
return Health.up().build()
}
private fun check(): Int {
// perform some specific health check
return ...
}
}
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 .
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Health indicators are usually called over HTTP and need to respond before any connection timeouts.
Spring Boot will log a warning message for any health indicator that takes longer than 10 seconds to respond.
If you want to configure this threshold, you can use the management.endpoint.health.logging.slow-indicator-threshold property.
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In addition to Spring Boot’s predefined Status
types, Health
can return a custom Status
that represents a new system state.
In such cases, you also need to provide a custom implementation of the StatusAggregator
interface, or you must configure the default implementation by using the management.endpoint.health.status.order
configuration property.
For example, assume a new Status
with a code of FATAL
is being used in one of your HealthIndicator
implementations.
To configure the severity order, add the following property to your application properties:
management.endpoint.health.status.order=fatal,down,out-of-service,unknown,up
management:
endpoint:
health:
status:
order: "fatal,down,out-of-service,unknown,up"
The HTTP status code in the response reflects the overall health status.
By default, OUT_OF_SERVICE
and DOWN
map to 503.
Any unmapped health statuses, including UP
, map to 200.
You might also want to register custom status mappings if you access the health endpoint over HTTP.
Configuring a custom mapping disables the defaults mappings for DOWN
and OUT_OF_SERVICE
.
If you want to retain the default mappings, you must explicitly configure them, alongside any custom mappings.
For example, the following property maps FATAL
to 503 (service unavailable) and retains the default mappings for DOWN
and OUT_OF_SERVICE
:
management.endpoint.health.status.http-mapping.down=503
management.endpoint.health.status.http-mapping.fatal=503
management.endpoint.health.status.http-mapping.out-of-service=503
management:
endpoint:
health:
status:
http-mapping:
down: 503
fatal: 503
out-of-service: 503
If you need more control, you can define your own HttpCodeStatusMapper bean.
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The following table shows the default status mappings for the built-in statuses:
Status | Mapping |
---|---|
|
|
|
|
|
No mapping by default, so HTTP status is |
|
No mapping by default, so HTTP status is |
2.9.3. Reactive Health Indicators
For reactive applications, such as those that use Spring WebFlux, ReactiveHealthContributor
provides a non-blocking contract for getting application health.
Similar to a traditional HealthContributor
, health information is collected from the content of a ReactiveHealthContributorRegistry
(by default, all HealthContributor
and ReactiveHealthContributor
instances defined in your ApplicationContext
).
Regular HealthContributors
that do not check against a reactive API are executed on the elastic scheduler.
In a reactive application, you should use the ReactiveHealthContributorRegistry to register and unregister health indicators at runtime.
If you need to register a regular HealthContributor , you should wrap it with ReactiveHealthContributor#adapt .
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To provide custom health information from a reactive API, you can register Spring beans that implement the ReactiveHealthIndicator
interface.
The following code shows a sample ReactiveHealthIndicator
implementation:
@Component
public class MyReactiveHealthIndicator implements ReactiveHealthIndicator {
@Override
public Mono<Health> health() {
return doHealthCheck().onErrorResume((exception) ->
Mono.just(new Health.Builder().down(exception).build()));
}
private Mono<Health> doHealthCheck() {
// perform some specific health check
return ...
}
}
@Component
class MyReactiveHealthIndicator : ReactiveHealthIndicator {
override fun health(): Mono<Health> {
return doHealthCheck()!!.onErrorResume { exception: Throwable? ->
Mono.just(Health.Builder().down(exception).build())
}
}
private fun doHealthCheck(): Mono<Health>? {
// perform some specific health check
return ...
}
}
To handle the error automatically, consider extending from AbstractReactiveHealthIndicator .
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2.9.4. Auto-configured ReactiveHealthIndicators
When appropriate, Spring Boot auto-configures the following ReactiveHealthIndicators
:
Key | Name | Description |
---|---|---|
|
Checks that a Cassandra database is up. |
|
|
Checks that a Couchbase cluster is up. |
|
|
Checks that an Elasticsearch cluster is up. |
|
|
Checks that a Mongo database is up. |
|
|
Checks that a Neo4j database is up. |
|
|
Checks that a Redis server is up. |
If necessary, reactive indicators replace the regular ones.
Also, any HealthIndicator that is not handled explicitly is wrapped automatically.
|
2.9.5. Health Groups
It is sometimes useful to organize health indicators into groups that you can use for different purposes.
To create a health indicator group, you can use the management.endpoint.health.group.<name>
property and specify a list of health indicator IDs to include
or exclude
.
For example, to create a group that includes only database indicators you can define the following:
management.endpoint.health.group.custom.include=db
management:
endpoint:
health:
group:
custom:
include: "db"
You can then check the result by hitting localhost:8080/actuator/health/custom
.
Similarly, to create a group that excludes the database indicators from the group and includes all the other indicators, you can define the following:
management.endpoint.health.group.custom.exclude=db
management:
endpoint:
health:
group:
custom:
exclude: "db"
By default, startup will fail if a health group includes or excludes a health indicator that does not exist.
To disable this behavior set management.endpoint.health.validate-group-membership
to false
.
By default, groups inherit the same StatusAggregator
and HttpCodeStatusMapper
settings as the system health.
However, you can also define these on a per-group basis.
You can also override the show-details
and roles
properties if required:
management.endpoint.health.group.custom.show-details=when-authorized
management.endpoint.health.group.custom.roles=admin
management.endpoint.health.group.custom.status.order=fatal,up
management.endpoint.health.group.custom.status.http-mapping.fatal=500
management.endpoint.health.group.custom.status.http-mapping.out-of-service=500
management:
endpoint:
health:
group:
custom:
show-details: "when-authorized"
roles: "admin"
status:
order: "fatal,up"
http-mapping:
fatal: 500
out-of-service: 500
You can use @Qualifier("groupname") if you need to register custom StatusAggregator or HttpCodeStatusMapper beans for use with the group.
|
A health group can also include/exclude a CompositeHealthContributor
.
You can also include/exclude only a certain component of a CompositeHealthContributor
.
This can be done using the fully qualified name of the component as follows:
management.endpoint.health.group.custom.include="test/primary"
management.endpoint.health.group.custom.exclude="test/primary/b"
In the example above, the custom
group will include the HealthContributor
with the name primary
which is a component of the composite test
.
Here, primary
itself is a composite and the HealthContributor
with the name b
will be excluded from the custom
group.
Health groups can be made available at an additional path on either the main or management port. This is useful in cloud environments such as Kubernetes, where it is quite common to use a separate management port for the actuator endpoints for security purposes. Having a separate port could lead to unreliable health checks because the main application might not work properly even if the health check is successful. The health group can be configured with an additional path as follows:
management.endpoint.health.group.live.additional-path="server:/healthz"
This would make the live
health group available on the main server port at /healthz
.
The prefix is mandatory and must be either server:
(represents the main server port) or management:
(represents the management port, if configured.)
The path must be a single path segment.
2.9.6. DataSource Health
The DataSource
health indicator shows the health of both standard data sources and routing data source beans.
The health of a routing data source includes the health of each of its target data sources.
In the health endpoint’s response, each of a routing data source’s targets is named by using its routing key.
If you prefer not to include routing data sources in the indicator’s output, set management.health.db.ignore-routing-data-sources
to true
.
2.10. Kubernetes Probes
Applications deployed on Kubernetes can provide information about their internal state with Container Probes. Depending on your Kubernetes configuration, the kubelet calls those probes and reacts to the result.
By default, Spring Boot manages your Application Availability State.
If deployed in a Kubernetes environment, actuator gathers the “Liveness” and “Readiness” information from the ApplicationAvailability
interface and uses that information in dedicated health indicators: LivenessStateHealthIndicator
and ReadinessStateHealthIndicator
.
These indicators are shown on the global health endpoint ("/actuator/health"
).
They are also exposed as separate HTTP Probes by using health groups: "/actuator/health/liveness"
and "/actuator/health/readiness"
.
You can then configure your Kubernetes infrastructure with the following endpoint information:
livenessProbe:
httpGet:
path: "/actuator/health/liveness"
port: <actuator-port>
failureThreshold: ...
periodSeconds: ...
readinessProbe:
httpGet:
path: "/actuator/health/readiness"
port: <actuator-port>
failureThreshold: ...
periodSeconds: ...
<actuator-port> should be set to the port that the actuator endpoints are available on.
It could be the main web server port or a separate management port if the "management.server.port" property has been set.
|
These health groups are automatically enabled only if the application runs in a Kubernetes environment.
You can enable them in any environment by using the management.endpoint.health.probes.enabled
configuration property.
If an application takes longer to start than the configured liveness period, Kubernetes mentions the "startupProbe" as a possible solution.
Generally speaking, the "startupProbe" is not necessarily needed here, as the "readinessProbe" fails until all startup tasks are done.
This means your application will not receive traffic until it is ready.
However, if your application takes a long time to start, consider using a "startupProbe" to make sure that Kubernetes won’t kill your application while it is in the process of starting.
See the section that describes how probes behave during the application lifecycle.
|
If your Actuator endpoints are deployed on a separate management context, the endpoints do not use the same web infrastructure (port, connection pools, framework components) as the main application.
In this case, a probe check could be successful even if the main application does not work properly (for example, it cannot accept new connections).
For this reason, is it a good idea to make the liveness
and readiness
health groups available on the main server port.
This can be done by setting the following property:
management.endpoint.health.probes.add-additional-paths=true
This would make the liveness
group available at /livez
and the readiness
group available at /readyz
on the main server port.
Paths can be customized using the additional-path
property on each group, see health groups for details.
2.10.1. Checking External State With Kubernetes Probes
Actuator configures the “liveness” and “readiness” probes as Health Groups. This means that all the health groups features are available for them. You can, for example, configure additional Health Indicators:
management.endpoint.health.group.readiness.include=readinessState,customCheck
management:
endpoint:
health:
group:
readiness:
include: "readinessState,customCheck"
By default, Spring Boot does not add other health indicators to these groups.
The “liveness” probe should not depend on health checks for external systems. If the liveness state of an application is broken, Kubernetes tries to solve that problem by restarting the application instance. This means that if an external system (such as a database, a Web API, or an external cache) fails, Kubernetes might restart all application instances and create cascading failures.
As for the “readiness” probe, the choice of checking external systems must be made carefully by the application developers. For this reason, Spring Boot does not include any additional health checks in the readiness probe. If the readiness state of an application instance is unready, Kubernetes does not route traffic to that instance. Some external systems might not be shared by application instances, in which case they could be included in a readiness probe. Other external systems might not be essential to the application (the application could have circuit breakers and fallbacks), in which case they definitely should not be included. Unfortunately, an external system that is shared by all application instances is common, and you have to make a judgement call: Include it in the readiness probe and expect that the application is taken out of service when the external service is down or leave it out and deal with failures higher up the stack, perhaps by using a circuit breaker in the caller.
If all instances of an application are unready, a Kubernetes Service with type=ClusterIP or NodePort does not accept any incoming connections.
There is no HTTP error response (503 and so on), since there is no connection.
A service with type=LoadBalancer might or might not accept connections, depending on the provider.
A service that has an explicit ingress also responds in a way that depends on the implementation — the ingress service itself has to decide how to handle the “connection refused” from downstream.
HTTP 503 is quite likely in the case of both load balancer and ingress.
|
Also, if an application uses Kubernetes autoscaling, it may react differently to applications being taken out of the load-balancer, depending on its autoscaler configuration.
2.10.2. Application Lifecycle and Probe States
An important aspect of the Kubernetes Probes support is its consistency with the application lifecycle.
There is a significant difference between the AvailabilityState
(which is the in-memory, internal state of the application)
and the actual probe (which exposes that state).
Depending on the phase of application lifecycle, the probe might not be available.
Spring Boot publishes application events during startup and shutdown,
and probes can listen to such events and expose the AvailabilityState
information.
The following tables show the AvailabilityState
and the state of HTTP connectors at different stages.
When a Spring Boot application starts:
Startup phase | LivenessState | ReadinessState | HTTP server | Notes |
---|---|---|---|---|
Starting |
|
|
Not started |
Kubernetes checks the "liveness" Probe and restarts the application if it takes too long. |
Started |
|
|
Refuses requests |
The application context is refreshed. The application performs startup tasks and does not receive traffic yet. |
Ready |
|
|
Accepts requests |
Startup tasks are finished. The application is receiving traffic. |
When a Spring Boot application shuts down:
Shutdown phase | Liveness State | Readiness State | HTTP server | Notes |
---|---|---|---|---|
Running |
|
|
Accepts requests |
Shutdown has been requested. |
Graceful shutdown |
|
|
New requests are rejected |
If enabled, graceful shutdown processes in-flight requests. |
Shutdown complete |
N/A |
N/A |
Server is shut down |
The application context is closed and the application is shut down. |
See Kubernetes container lifecycle section for more information about Kubernetes deployment. |
2.11. Application Information
Application information exposes various information collected from all InfoContributor
beans defined in your ApplicationContext
.
Spring Boot includes a number of auto-configured InfoContributor
beans, and you can write your own.
2.11.1. Auto-configured InfoContributors
When appropriate, Spring auto-configures the following InfoContributor
beans:
ID | Name | Description | Prerequisites |
---|---|---|---|
|
Exposes build information. |
A |
|
|
Exposes any property from the |
None. |
|
|
Exposes git information. |
A |
|
|
Exposes Java runtime information. |
None. |
|
|
Exposes Operating System information. |
None. |
Whether an individual contributor is enabled is controlled by its management.info.<id>.enabled
property.
Different contributors have different defaults for this property, depending on their prerequisites and the nature of the information that they expose.
With no prerequisites to indicate that they should be enabled, the env
, java
, and os
contributors are disabled by default.
Each can be enabled by setting its management.info.<id>.enabled
property to true
.
The build
and git
info contributors are enabled by default.
Each can be disabled by setting its management.info.<id>.enabled
property to false
.
Alternatively, to disable every contributor that is usually enabled by default, set the management.info.defaults.enabled
property to false
.
2.11.2. Custom Application Information
When the env
contributor is enabled, 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:
info.app.encoding=UTF-8
info.app.java.source=17
info.app.java.target=17
info:
app:
encoding: "UTF-8"
java:
source: "17"
target: "17"
Rather than hardcoding those values, you could also expand info properties at build time. Assuming you use Maven, you could rewrite the preceding example as follows: Properties
Yaml
|
2.11.3. 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, you can use the info
endpoint to expose these properties.
A GitProperties bean is auto-configured if a git.properties file is available at the root of the classpath.
See "how to generate git information" for more detail.
|
By default, the endpoint exposes git.branch
, git.commit.id
, and git.commit.time
properties, if present.
If you do not want any of these properties in the endpoint response, they need to be excluded from the git.properties
file.
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:
management.info.git.mode=full
management:
info:
git:
mode: "full"
To disable the git commit information from the info
endpoint completely, set the management.info.git.enabled
property to false
, as follows:
management.info.git.enabled=false
management:
info:
git:
enabled: false
2.11.4. 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.
The Maven and Gradle plugins can both generate that file. See "how to generate build information" for more details. |
2.11.5. Java Information
The info
endpoint publishes information about your Java runtime environment, see JavaInfo
for more details.
2.11.6. OS Information
The info
endpoint publishes information about your Operating System, see OsInfo
for more details.
2.11.7. Writing Custom InfoContributors
To provide custom application information, you can register Spring beans that implement the InfoContributor
interface.
The following example contributes an example
entry with a single value:
@Component
public class MyInfoContributor implements InfoContributor {
@Override
public void contribute(Info.Builder builder) {
builder.withDetail("example", Collections.singletonMap("key", "value"));
}
}
@Component
class MyInfoContributor : InfoContributor {
override fun contribute(builder: Info.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:
{
"example": {
"key" : "value"
}
}
3. Monitoring and Management Over HTTP
If you are developing a web 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 /actuator
as the URL path.
For example, health
is exposed as /actuator/health
.
Actuator is supported natively with Spring MVC, Spring WebFlux, and Jersey. If both Jersey and Spring MVC are available, Spring MVC is used. |
Jackson is a required dependency in order to get the correct JSON responses as documented in the API documentation (HTML or PDF). |
3.1. Customizing the Management Endpoint Paths
Sometimes, it is useful to customize the prefix for the management endpoints.
For example, your application might already use /actuator
for another purpose.
You can use the management.endpoints.web.base-path
property to change the prefix for your management endpoint, as the following example shows:
management.endpoints.web.base-path=/manage
management:
endpoints:
web:
base-path: "/manage"
The preceding application.properties
example changes the endpoint from /actuator/{id}
to /manage/{id}
(for example, /manage/info
).
Unless the management port has been configured to expose endpoints by using a different HTTP port, management.endpoints.web.base-path is relative to server.servlet.context-path (for servlet web applications) or spring.webflux.base-path (for reactive web applications).
If management.server.port is configured, management.endpoints.web.base-path is relative to management.server.base-path .
|
If you want to map endpoints to a different path, you can use the management.endpoints.web.path-mapping
property.
The following example remaps /actuator/health
to /healthcheck
:
management.endpoints.web.base-path=/
management.endpoints.web.path-mapping.health=healthcheck
management:
endpoints:
web:
base-path: "/"
path-mapping:
health: "healthcheck"
3.2. 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 the following example shows:
management.server.port=8081
management:
server:
port: 8081
On Cloud Foundry, by default, applications receive requests only on port 8080 for both HTTP and TCP routing. If you want to use a custom management port on Cloud Foundry, you need to explicitly set up the application’s routes to forward traffic to the custom port. |
3.3. Configuring Management-specific SSL
When configured to use a custom port, you can also configure the management server with its own SSL by using the various management.server.ssl.*
properties.
For example, doing so lets a management server be available over HTTP while the main application uses HTTPS, as the following property settings show:
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
server:
port: 8443
ssl:
enabled: true
key-store: "classpath:store.jks"
key-password: "secret"
management:
server:
port: 8080
ssl:
enabled: false
Alternatively, both the main server and the management server can use SSL but with different key stores, as follows:
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
server:
port: 8443
ssl:
enabled: true
key-store: "classpath:main.jks"
key-password: "secret"
management:
server:
port: 8080
ssl:
enabled: true
key-store: "classpath:management.jks"
key-password: "secret"
3.4. Customizing the Management Server Address
You can customize the address on which the management endpoints are available 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
.
You can listen on a different address only when the port differs from the main server port. |
The following example application.properties
does not allow remote management connections:
management.server.port=8081
management.server.address=127.0.0.1
management:
server:
port: 8081
address: "127.0.0.1"
3.5. Disabling HTTP Endpoints
If you do not want to expose endpoints over HTTP, you can set the management port to -1
, as the following example shows:
management.server.port=-1
management:
server:
port: -1
You can also achieve this by using the management.endpoints.web.exposure.exclude
property, as the following example shows:
management.endpoints.web.exposure.exclude=*
management:
endpoints:
web:
exposure:
exclude: "*"
4. Monitoring and Management over JMX
Java Management Extensions (JMX) provide a standard mechanism to monitor and manage applications.
By default, this feature is not enabled.
You can turn it on by setting the spring.jmx.enabled
configuration property to true
.
Spring Boot exposes the most suitable MBeanServer
as a bean with an ID of mbeanServer
.
Any of your beans that are annotated with Spring JMX annotations (@ManagedResource
, @ManagedAttribute
, or @ManagedOperation
) are exposed to it.
If your platform provides a standard MBeanServer
, Spring Boot uses that and defaults to the VM MBeanServer
, if necessary.
If all that fails, a new MBeanServer
is created.
See the JmxAutoConfiguration
class for more details.
By default, Spring Boot also exposes management endpoints as JMX MBeans under the org.springframework.boot
domain.
To take full control over endpoint registration in the JMX domain, consider registering your own EndpointObjectNameFactory
implementation.
4.1. 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 spring.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
:
spring.jmx.unique-names=true
management.endpoints.jmx.domain=com.example.myapp
spring:
jmx:
unique-names: true
management:
endpoints:
jmx:
domain: "com.example.myapp"
5. Observability
Observability is the ability to observe the internal state of a running system from the outside. It consists of the three pillars logging, metrics and traces.
For metrics and traces, Spring Boot uses Micrometer Observation.
To create your own observations (which will lead to metrics and traces), you can inject an ObservationRegistry
.
@Component
public class MyCustomObservation {
private final ObservationRegistry observationRegistry;
public MyCustomObservation(ObservationRegistry observationRegistry) {
this.observationRegistry = observationRegistry;
}
public void doSomething() {
Observation.createNotStarted("doSomething", this.observationRegistry)
.lowCardinalityKeyValue("locale", "en-US")
.highCardinalityKeyValue("userId", "42")
.observe(() -> {
// Execute business logic here
});
}
}
Low cardinality key-values will be added to metrics and traces, while high cardinality key-values will only be added to traces. |
Beans of type ObservationPredicate
, GlobalObservationConvention
, ObservationFilter
and ObservationHandler
will be automatically registered on the ObservationRegistry
.
You can additionally register any number of ObservationRegistryCustomizer
beans to further configure the registry.
Observability support relies on the Context Propagation library for forwarding the current observation across threads and reactive pipelines.
By default, ThreadLocal
values are not automatically reinstated in reactive operators.
This behavior is controlled with the spring.reactor.context-propagation
property, which can be set to auto
to enable automatic propagation.
For more details about observations please see the Micrometer Observation documentation.
Observability for JDBC can be configured using a separate project. The Datasource Micrometer project provides a Spring Boot starter which automatically creates observations when JDBC operations are invoked. Read more about it in the reference documentation. |
Observability for R2DBC is built into Spring Boot.
To enable it, add the io.r2dbc:r2dbc-proxy dependency to your project.
|
5.1. Common Key-Values
Common key-values are generally used for dimensional drill-down on the operating environment, such as host, instance, region, stack, and others. Common key-values are applied to all observations as low cardinality key-values and can be configured, as the following example shows:
management.observations.key-values.region=us-east-1
management.observations.key-values.stack=prod
management:
observations:
key-values:
region: "us-east-1"
stack: "prod"
The preceding example adds region
and stack
key-values to all observations with a value of us-east-1
and prod
, respectively.
5.2. Preventing Observations
If you’d like to prevent some observations from being reported, you can use the management.observations.enable
properties:
management.observations.enable.denied.prefix=false
management.observations.enable.another.denied.prefix=false
management:
observations:
enable:
denied:
prefix: false
another:
denied:
prefix: false
The preceding example will prevent all observations with a name starting with denied.prefix
or another.denied.prefix
.
If you want to prevent Spring Security from reporting observations, set the property management.observations.enable.spring.security to false .
|
If you need greater control over the prevention of observations, you can register beans of type ObservationPredicate
.
Observations are only reported if all the ObservationPredicate
beans return true
for that observation.
@Component
class MyObservationPredicate implements ObservationPredicate {
@Override
public boolean test(String name, Context context) {
return !name.contains("denied");
}
}
The preceding example will prevent all observations whose name contains "denied".
5.3. OpenTelemetry Support
Spring Boot’s actuator module includes basic support for OpenTelemetry.
It provides a bean of type OpenTelemetry
, and if there are beans of type SdkTracerProvider
, ContextPropagators
, SdkLoggerProvider
or SdkMeterProvider
in the application context, they automatically get registered.
Additionally, it provides a Resource
bean.
The attributes of the Resource
can be configured via the management.opentelemetry.resource-attributes
configuration property.
Spring Boot does not provide auto-configuration for OpenTelemetry metrics or logging. OpenTelemetry tracing is only auto-configured when used together with Micrometer Tracing. |
The next sections will provide more details about logging, metrics and traces.
6. 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.
6.1. Configure a Logger
To configure a given logger, POST
a partial entity to the resource’s URI, as the following example shows:
{
"configuredLevel": "DEBUG"
}
To “reset” the specific level of the logger (and use the default configuration instead), you can pass a value of null as the configuredLevel .
|
7. Metrics
Spring Boot Actuator provides dependency management and auto-configuration for Micrometer, an application metrics facade that supports numerous monitoring systems, including:
To learn more about Micrometer’s capabilities, see its reference documentation, in particular the concepts section. |
7.1. Getting started
Spring Boot auto-configures a composite MeterRegistry
and adds a registry to the composite for each of the supported implementations that it finds on the classpath.
Having a dependency on micrometer-registry-{system}
in your runtime classpath is enough for Spring Boot to configure the registry.
Most registries share common features. For instance, you can disable a particular registry even if the Micrometer registry implementation is on the classpath. The following example disables Datadog:
management.datadog.metrics.export.enabled=false
management:
datadog:
metrics:
export:
enabled: false
You can also disable all registries unless stated otherwise by the registry-specific property, as the following example shows:
management.defaults.metrics.export.enabled=false
management:
defaults:
metrics:
export:
enabled: false
Spring Boot also adds any auto-configured registries to the global static composite registry on the Metrics
class, unless you explicitly tell it not to:
management.metrics.use-global-registry=false
management:
metrics:
use-global-registry: false
You can register any number of MeterRegistryCustomizer
beans to further configure the registry, such as applying common tags, before any meters are registered with the registry:
@Configuration(proxyBeanMethods = false)
public class MyMeterRegistryConfiguration {
@Bean
public MeterRegistryCustomizer<MeterRegistry> metricsCommonTags() {
return (registry) -> registry.config().commonTags("region", "us-east-1");
}
}
@Configuration(proxyBeanMethods = false)
class MyMeterRegistryConfiguration {
@Bean
fun metricsCommonTags(): MeterRegistryCustomizer<MeterRegistry> {
return MeterRegistryCustomizer { registry ->
registry.config().commonTags("region", "us-east-1")
}
}
}
You can apply customizations to particular registry implementations by being more specific about the generic type:
@Configuration(proxyBeanMethods = false)
public class MyMeterRegistryConfiguration {
@Bean
public MeterRegistryCustomizer<GraphiteMeterRegistry> graphiteMetricsNamingConvention() {
return (registry) -> registry.config().namingConvention(this::name);
}
private String name(String name, Meter.Type type, String baseUnit) {
return ...
}
}
@Configuration(proxyBeanMethods = false)
class MyMeterRegistryConfiguration {
@Bean
fun graphiteMetricsNamingConvention(): MeterRegistryCustomizer<GraphiteMeterRegistry> {
return MeterRegistryCustomizer { registry: GraphiteMeterRegistry ->
registry.config().namingConvention(this::name)
}
}
private fun name(name: String, type: Meter.Type, baseUnit: String?): String {
return ...
}
}
Spring Boot also configures built-in instrumentation that you can control through configuration or dedicated annotation markers.
7.2. Supported Monitoring Systems
This section briefly describes each of the supported monitoring systems.
7.2.1. AppOptics
By default, the AppOptics registry periodically pushes metrics to api.appoptics.com/v1/measurements
.
To export metrics to SaaS AppOptics, your API token must be provided:
management.appoptics.metrics.export.api-token=YOUR_TOKEN
management:
appoptics:
metrics:
export:
api-token: "YOUR_TOKEN"
7.2.2. Atlas
By default, metrics are exported to Atlas running on your local machine. You can provide the location of the Atlas server:
management.atlas.metrics.export.uri=https://atlas.example.com:7101/api/v1/publish
management:
atlas:
metrics:
export:
uri: "https://atlas.example.com:7101/api/v1/publish"
7.2.3. Datadog
A Datadog registry periodically pushes metrics to datadoghq. To export metrics to Datadog, you must provide your API key:
management.datadog.metrics.export.api-key=YOUR_KEY
management:
datadog:
metrics:
export:
api-key: "YOUR_KEY"
If you additionally provide an application key (optional), then metadata such as meter descriptions, types, and base units will also be exported:
management.datadog.metrics.export.api-key=YOUR_API_KEY
management.datadog.metrics.export.application-key=YOUR_APPLICATION_KEY
management:
datadog:
metrics:
export:
api-key: "YOUR_API_KEY"
application-key: "YOUR_APPLICATION_KEY"
By default, metrics are sent to the Datadog US site (api.datadoghq.com
).
If your Datadog project is hosted on one of the other sites, or you need to send metrics through a proxy, configure the URI accordingly:
management.datadog.metrics.export.uri=https://api.datadoghq.eu
management:
datadog:
metrics:
export:
uri: "https://api.datadoghq.eu"
You can also change the interval at which metrics are sent to Datadog:
management.datadog.metrics.export.step=30s
management:
datadog:
metrics:
export:
step: "30s"
7.2.4. Dynatrace
Dynatrace offers two metrics ingest APIs, both of which are implemented for Micrometer.
You can find the Dynatrace documentation on Micrometer metrics ingest here.
Configuration properties in the v1
namespace apply only when exporting to the Timeseries v1 API.
Configuration properties in the v2
namespace apply only when exporting to the Metrics v2 API.
Note that this integration can export only to either the v1
or v2
version of the API at a time, with v2
being preferred.
If the device-id
(required for v1 but not used in v2) is set in the v1
namespace, metrics are exported to the v1
endpoint.
Otherwise, v2
is assumed.
v2 API
You can use the v2 API in two ways.
Auto-configuration
Dynatrace auto-configuration is available for hosts that are monitored by the OneAgent or by the Dynatrace Operator for Kubernetes.
Local OneAgent: If a OneAgent is running on the host, metrics are automatically exported to the local OneAgent ingest endpoint. The ingest endpoint forwards the metrics to the Dynatrace backend.
Dynatrace Kubernetes Operator: When running in Kubernetes with the Dynatrace Operator installed, the registry will automatically pick up your endpoint URI and API token from the operator instead.
This is the default behavior and requires no special setup beyond a dependency on io.micrometer:micrometer-registry-dynatrace
.
Manual configuration
If no auto-configuration is available, the endpoint of the Metrics v2 API and an API token are required.
The API token must have the “Ingest metrics” (metrics.ingest
) permission set.
We recommend limiting the scope of the token to this one permission.
You must ensure that the endpoint URI contains the path (for example, /api/v2/metrics/ingest
):
The URL of the Metrics API v2 ingest endpoint is different according to your deployment option:
-
SaaS:
https://{your-environment-id}.live.dynatrace.com/api/v2/metrics/ingest
-
Managed deployments:
https://{your-domain}/e/{your-environment-id}/api/v2/metrics/ingest
The example below configures metrics export using the example
environment id:
management.dynatrace.metrics.export.uri=https://example.live.dynatrace.com/api/v2/metrics/ingest
management.dynatrace.metrics.export.api-token=YOUR_TOKEN
management:
dynatrace:
metrics:
export:
uri: "https://example.live.dynatrace.com/api/v2/metrics/ingest"
api-token: "YOUR_TOKEN"
When using the Dynatrace v2 API, the following optional features are available (more details can be found in the Dynatrace documentation):
-
Metric key prefix: Sets a prefix that is prepended to all exported metric keys.
-
Enrich with Dynatrace metadata: If a OneAgent or Dynatrace operator is running, enrich metrics with additional metadata (for example, about the host, process, or pod).
-
Default dimensions: Specify key-value pairs that are added to all exported metrics. If tags with the same key are specified with Micrometer, they overwrite the default dimensions.
-
Use Dynatrace Summary instruments: In some cases the Micrometer Dynatrace registry created metrics that were rejected. In Micrometer 1.9.x, this was fixed by introducing Dynatrace-specific summary instruments. Setting this toggle to
false
forces Micrometer to fall back to the behavior that was the default before 1.9.x. It should only be used when encountering problems while migrating from Micrometer 1.8.x to 1.9.x. -
Export meter metadata: Starting from Micrometer 1.12.0, the Dynatrace exporter will also export meter metadata, such as unit and description by default. Use the
export-meter-metadata
toggle to turn this feature off.
It is possible to not specify a URI and API token, as shown in the following example. In this scenario, the automatically configured endpoint is used:
management.dynatrace.metrics.export.v2.metric-key-prefix=your.key.prefix
management.dynatrace.metrics.export.v2.enrich-with-dynatrace-metadata=true
management.dynatrace.metrics.export.v2.default-dimensions.key1=value1
management.dynatrace.metrics.export.v2.default-dimensions.key2=value2
management.dynatrace.metrics.export.v2.use-dynatrace-summary-instruments=true
management.dynatrace.metrics.export.v2.export-meter-metadata=true
management:
dynatrace:
metrics:
export:
# Specify uri and api-token here if not using the local OneAgent endpoint.
v2:
metric-key-prefix: "your.key.prefix"
enrich-with-dynatrace-metadata: true
default-dimensions:
key1: "value1"
key2: "value2"
use-dynatrace-summary-instruments: true # (default: true)
export-meter-metadata: true # (default: true)
v1 API (Legacy)
The Dynatrace v1 API metrics registry pushes metrics to the configured URI periodically by using the Timeseries v1 API.
For backwards-compatibility with existing setups, when device-id
is set (required for v1, but not used in v2), metrics are exported to the Timeseries v1 endpoint.
To export metrics to Dynatrace, your API token, device ID, and URI must be provided:
management.dynatrace.metrics.export.uri=https://{your-environment-id}.live.dynatrace.com
management.dynatrace.metrics.export.api-token=YOUR_TOKEN
management.dynatrace.metrics.export.v1.device-id=YOUR_DEVICE_ID
management:
dynatrace:
metrics:
export:
uri: "https://{your-environment-id}.live.dynatrace.com"
api-token: "YOUR_TOKEN"
v1:
device-id: "YOUR_DEVICE_ID"
For the v1 API, you must specify the base environment URI without a path, as the v1 endpoint path is added automatically.
Version-independent Settings
In addition to the API endpoint and token, you can also change the interval at which metrics are sent to Dynatrace.
The default export interval is 60s
.
The following example sets the export interval to 30 seconds:
management.dynatrace.metrics.export.step=30s
management:
dynatrace:
metrics:
export:
step: "30s"
You can find more information on how to set up the Dynatrace exporter for Micrometer in the Micrometer documentation and the Dynatrace documentation.
7.2.5. Elastic
By default, metrics are exported to Elastic running on your local machine. You can provide the location of the Elastic server to use by using the following property:
management.elastic.metrics.export.host=https://elastic.example.com:8086
management:
elastic:
metrics:
export:
host: "https://elastic.example.com:8086"
7.2.6. Ganglia
By default, metrics are exported to Ganglia running on your local machine. You can provide the Ganglia server host and port, as the following example shows:
management.ganglia.metrics.export.host=ganglia.example.com
management.ganglia.metrics.export.port=9649
management:
ganglia:
metrics:
export:
host: "ganglia.example.com"
port: 9649
7.2.7. Graphite
By default, metrics are exported to Graphite running on your local machine. You can provide the Graphite server host and port, as the following example shows:
management.graphite.metrics.export.host=graphite.example.com
management.graphite.metrics.export.port=9004
management:
graphite:
metrics:
export:
host: "graphite.example.com"
port: 9004
Micrometer provides a default HierarchicalNameMapper
that governs how a dimensional meter ID is mapped to flat hierarchical names.
To take control over this behavior, define your Java
Kotlin
|
7.2.8. Humio
By default, the Humio registry periodically pushes metrics to cloud.humio.com. To export metrics to SaaS Humio, you must provide your API token:
management.humio.metrics.export.api-token=YOUR_TOKEN
management:
humio:
metrics:
export:
api-token: "YOUR_TOKEN"
You should also configure one or more tags to identify the data source to which metrics are pushed:
management.humio.metrics.export.tags.alpha=a
management.humio.metrics.export.tags.bravo=b
management:
humio:
metrics:
export:
tags:
alpha: "a"
bravo: "b"
7.2.9. Influx
By default, metrics are exported to an Influx v1 instance running on your local machine with the default configuration.
To export metrics to InfluxDB v2, configure the org
, bucket
, and authentication token
for writing metrics.
You can provide the location of the Influx server to use by using:
management.influx.metrics.export.uri=https://influx.example.com:8086
management:
influx:
metrics:
export:
uri: "https://influx.example.com:8086"
7.2.10. JMX
Micrometer provides a hierarchical mapping to JMX, primarily as a cheap and portable way to view metrics locally.
By default, metrics are exported to the metrics
JMX domain.
You can provide the domain to use by using:
management.jmx.metrics.export.domain=com.example.app.metrics
management:
jmx:
metrics:
export:
domain: "com.example.app.metrics"
Micrometer provides a default HierarchicalNameMapper
that governs how a dimensional meter ID is mapped to flat hierarchical names.
To take control over this behavior, define your Java
Kotlin
|
7.2.11. KairosDB
By default, metrics are exported to KairosDB running on your local machine. You can provide the location of the KairosDB server to use by using:
management.kairos.metrics.export.uri=https://kairosdb.example.com:8080/api/v1/datapoints
management:
kairos:
metrics:
export:
uri: "https://kairosdb.example.com:8080/api/v1/datapoints"
7.2.12. New Relic
A New Relic registry periodically pushes metrics to New Relic. To export metrics to New Relic, you must provide your API key and account ID:
management.newrelic.metrics.export.api-key=YOUR_KEY
management.newrelic.metrics.export.account-id=YOUR_ACCOUNT_ID
management:
newrelic:
metrics:
export:
api-key: "YOUR_KEY"
account-id: "YOUR_ACCOUNT_ID"
You can also change the interval at which metrics are sent to New Relic:
management.newrelic.metrics.export.step=30s
management:
newrelic:
metrics:
export:
step: "30s"
By default, metrics are published through REST calls, but you can also use the Java Agent API if you have it on the classpath:
management.newrelic.metrics.export.client-provider-type=insights-agent
management:
newrelic:
metrics:
export:
client-provider-type: "insights-agent"
Finally, you can take full control by defining your own NewRelicClientProvider
bean.
7.2.13. OpenTelemetry
By default, metrics are exported to OpenTelemetry running on your local machine. You can provide the location of the OpenTelemetry metric endpoint to use by using:
management.otlp.metrics.export.url=https://otlp.example.com:4318/v1/metrics
management:
otlp:
metrics:
export:
url: "https://otlp.example.com:4318/v1/metrics"
7.2.14. Prometheus
Prometheus expects to scrape or poll individual application instances for metrics.
Spring Boot provides an actuator endpoint at /actuator/prometheus
to present a Prometheus scrape with the appropriate format.
By default, the endpoint is not available and must be exposed. See exposing endpoints for more details. |
The following example scrape_config
adds to prometheus.yml
:
scrape_configs:
- job_name: "spring"
metrics_path: "/actuator/prometheus"
static_configs:
- targets: ["HOST:PORT"]
Prometheus Exemplars are also supported.
To enable this feature, a SpanContextSupplier
bean should be present.
If you use Micrometer Tracing, this will be auto-configured for you, but you can always create your own if you want.
Please check the Prometheus Docs, since this feature needs to be explicitly enabled on Prometheus' side, and it is only supported using the OpenMetrics format.
For ephemeral or batch jobs that may not exist long enough to be scraped, you can use Prometheus Pushgateway support to expose the metrics to Prometheus. To enable Prometheus Pushgateway support, add the following dependency to your project:
<dependency>
<groupId>io.prometheus</groupId>
<artifactId>simpleclient_pushgateway</artifactId>
</dependency>
When the Prometheus Pushgateway dependency is present on the classpath and the management.prometheus.metrics.export.pushgateway.enabled
property is set to true
, a PrometheusPushGatewayManager
bean is auto-configured.
This manages the pushing of metrics to a Prometheus Pushgateway.
You can tune the PrometheusPushGatewayManager
by using properties under management.prometheus.metrics.export.pushgateway
.
For advanced configuration, you can also provide your own PrometheusPushGatewayManager
bean.
7.2.15. SignalFx
SignalFx registry periodically pushes metrics to SignalFx. To export metrics to SignalFx, you must provide your access token:
management.signalfx.metrics.export.access-token=YOUR_ACCESS_TOKEN
management:
signalfx:
metrics:
export:
access-token: "YOUR_ACCESS_TOKEN"
You can also change the interval at which metrics are sent to SignalFx:
management.signalfx.metrics.export.step=30s
management:
signalfx:
metrics:
export:
step: "30s"
7.2.16. Simple
Micrometer ships with a simple, in-memory backend that is automatically used as a fallback if no other registry is configured. This lets you see what metrics are collected in the metrics endpoint.
The in-memory backend disables itself as soon as you use any other available backend. You can also disable it explicitly:
management.simple.metrics.export.enabled=false
management:
simple:
metrics:
export:
enabled: false
7.2.17. Stackdriver
The Stackdriver registry periodically pushes metrics to Stackdriver. To export metrics to SaaS Stackdriver, you must provide your Google Cloud project ID:
management.stackdriver.metrics.export.project-id=my-project
management:
stackdriver:
metrics:
export:
project-id: "my-project"
You can also change the interval at which metrics are sent to Stackdriver:
management.stackdriver.metrics.export.step=30s
management:
stackdriver:
metrics:
export:
step: "30s"
7.2.18. StatsD
The StatsD registry eagerly pushes metrics over UDP to a StatsD agent. By default, metrics are exported to a StatsD agent running on your local machine. You can provide the StatsD agent host, port, and protocol to use by using:
management.statsd.metrics.export.host=statsd.example.com
management.statsd.metrics.export.port=9125
management.statsd.metrics.export.protocol=udp
management:
statsd:
metrics:
export:
host: "statsd.example.com"
port: 9125
protocol: "udp"
You can also change the StatsD line protocol to use (it defaults to Datadog):
management.statsd.metrics.export.flavor=etsy
management:
statsd:
metrics:
export:
flavor: "etsy"
7.2.19. Wavefront
The Wavefront registry periodically pushes metrics to Wavefront. If you are exporting metrics to Wavefront directly, you must provide your API token:
management.wavefront.api-token=YOUR_API_TOKEN
management:
wavefront:
api-token: "YOUR_API_TOKEN"
Alternatively, you can use a Wavefront sidecar or an internal proxy in your environment to forward metrics data to the Wavefront API host:
management.wavefront.uri=proxy://localhost:2878
management:
wavefront:
uri: "proxy://localhost:2878"
If you publish metrics to a Wavefront proxy (as described in the Wavefront documentation), the host must be in the proxy://HOST:PORT format.
|
You can also change the interval at which metrics are sent to Wavefront:
management.wavefront.metrics.export.step=30s
management:
wavefront:
metrics:
export:
step: "30s"
7.3. Supported Metrics and Meters
Spring Boot provides automatic meter registration for a wide variety of technologies. In most situations, the defaults provide sensible metrics that can be published to any of the supported monitoring systems.
7.3.1. JVM Metrics
Auto-configuration enables JVM Metrics by using core Micrometer classes.
JVM metrics are published under the jvm.
meter name.
The following JVM metrics are provided:
-
Various memory and buffer pool details
-
Statistics related to garbage collection
-
Thread utilization
-
The number of classes loaded and unloaded
-
JVM version information
-
JIT compilation time
7.3.2. System Metrics
Auto-configuration enables system metrics by using core Micrometer classes.
System metrics are published under the system.
, process.
, and disk.
meter names.
The following system metrics are provided:
-
CPU metrics
-
File descriptor metrics
-
Uptime metrics (both the amount of time the application has been running and a fixed gauge of the absolute start time)
-
Disk space available
7.3.3. Application Startup Metrics
Auto-configuration exposes application startup time metrics:
-
application.started.time
: time taken to start the application. -
application.ready.time
: time taken for the application to be ready to service requests.
Metrics are tagged by the fully qualified name of the application class.
7.3.4. Logger Metrics
Auto-configuration enables the event metrics for both Logback and Log4J2.
The details are published under the log4j2.events.
or logback.events.
meter names.
7.3.5. Task Execution and Scheduling Metrics
Auto-configuration enables the instrumentation of all available ThreadPoolTaskExecutor
and ThreadPoolTaskScheduler
beans, as long as the underling ThreadPoolExecutor
is available.
Metrics are tagged by the name of the executor, which is derived from the bean name.
7.3.6. JMS Metrics
Auto-configuration enables the instrumentation of all available JmsTemplate
beans.
JmsMessagingTemplate
instances built with instrumented JmsTemplate
beans will also record observations.
See the Spring Framework reference documentation for more information on produced observations.
7.3.7. Spring MVC Metrics
Auto-configuration enables the instrumentation of all requests handled by Spring MVC controllers and functional handlers.
By default, metrics are generated with the name, http.server.requests
.
You can customize the name by setting the management.observations.http.server.requests.name
property.
To add to the default tags, provide a @Bean
that extends DefaultServerRequestObservationConvention
from the org.springframework.http.server.observation
package.
To replace the default tags, provide a @Bean
that implements ServerRequestObservationConvention
.
In some cases, exceptions handled in web controllers are not recorded as request metrics tags. Applications can opt in and record exceptions by setting handled exceptions as request attributes. |
By default, all requests are handled.
To customize the filter, provide a @Bean
that implements FilterRegistrationBean<WebMvcMetricsFilter>
.
7.3.8. Spring WebFlux Metrics
Auto-configuration enables the instrumentation of all requests handled by Spring WebFlux controllers and functional handlers.
By default, metrics are generated with the name, http.server.requests
.
You can customize the name by setting the management.observations.http.server.requests.name
property.
To add to the default tags, provide a @Bean
that extends DefaultServerRequestObservationConvention
from the org.springframework.http.server.reactive.observation
package.
To replace the default tags, provide a @Bean
that implements ServerRequestObservationConvention
.
In some cases, exceptions handled in controllers and handler functions are not recorded as request metrics tags. Applications can opt in and record exceptions by setting handled exceptions as request attributes. |
7.3.9. Jersey Server Metrics
Auto-configuration enables the instrumentation of all requests handled by the Jersey JAX-RS implementation.
By default, metrics are generated with the name, http.server.requests
.
You can customize the name by setting the management.observations.http.server.requests.name
property.
By default, Jersey server metrics are tagged with the following information:
Tag | Description |
---|---|
|
The simple class name of any exception that was thrown while handling the request. |
|
The request’s method (for example, |
|
The request’s outcome, based on the status code of the response.
1xx is |
|
The response’s HTTP status code (for example, |
|
The request’s URI template prior to variable substitution, if possible (for example, |
To customize the tags, provide a @Bean
that implements JerseyTagsProvider
.
7.3.10. HTTP Client Metrics
Spring Boot Actuator manages the instrumentation of RestTemplate
, WebClient
and RestClient
.
For that, you have to inject the auto-configured builder and use it to create instances:
-
RestTemplateBuilder
forRestTemplate
-
WebClient.Builder
forWebClient
-
RestClient.Builder
forRestClient
You can also manually apply the customizers responsible for this instrumentation, namely ObservationRestTemplateCustomizer
, ObservationWebClientCustomizer
and ObservationRestClientCustomizer
.
By default, metrics are generated with the name, http.client.requests
.
You can customize the name by setting the management.observations.http.client.requests.name
property.
To customize the tags when using RestTemplate
or RestClient
, provide a @Bean
that implements ClientRequestObservationConvention
from the org.springframework.http.client.observation
package.
To customize the tags when using WebClient
, provide a @Bean
that implements ClientRequestObservationConvention
from the org.springframework.web.reactive.function.client
package.
7.3.11. Tomcat Metrics
Auto-configuration enables the instrumentation of Tomcat only when an MBeanRegistry
is enabled.
By default, the MBeanRegistry
is disabled, but you can enable it by setting server.tomcat.mbeanregistry.enabled
to true
.
Tomcat metrics are published under the tomcat.
meter name.
7.3.12. Cache Metrics
Auto-configuration enables the instrumentation of all available Cache
instances on startup, with metrics prefixed with cache
.
Cache instrumentation is standardized for a basic set of metrics.
Additional, cache-specific metrics are also available.
The following cache libraries are supported:
-
Cache2k
-
Caffeine
-
Hazelcast
-
Any compliant JCache (JSR-107) implementation
-
Redis
Metrics are tagged by the name of the cache and by the name of the CacheManager
, which is derived from the bean name.
Only caches that are configured on startup are bound to the registry.
For caches not defined in the cache’s configuration, such as caches created on the fly or programmatically after the startup phase, an explicit registration is required.
A CacheMetricsRegistrar bean is made available to make that process easier.
|
7.3.13. Spring Batch Metrics
See the Spring Batch reference documentation.
7.3.15. DataSource Metrics
Auto-configuration enables the instrumentation of all available DataSource
objects with metrics prefixed with jdbc.connections
.
Data source instrumentation results in gauges that represent the currently active, idle, maximum allowed, and minimum allowed connections in the pool.
Metrics are also tagged by the name of the DataSource
computed based on the bean name.
By default, Spring Boot provides metadata for all supported data sources.
You can add additional DataSourcePoolMetadataProvider beans if your favorite data source is not supported.
See DataSourcePoolMetadataProvidersConfiguration for examples.
|
Also, Hikari-specific metrics are exposed with a hikaricp
prefix.
Each metric is tagged by the name of the pool (you can control it with spring.datasource.name
).
7.3.16. Hibernate Metrics
If org.hibernate.orm:hibernate-micrometer
is on the classpath, all available Hibernate EntityManagerFactory
instances that have statistics enabled are instrumented with a metric named hibernate
.
Metrics are also tagged by the name of the EntityManagerFactory
, which is derived from the bean name.
To enable statistics, the standard JPA property hibernate.generate_statistics
must be set to true
.
You can enable that on the auto-configured EntityManagerFactory
:
spring.jpa.properties[hibernate.generate_statistics]=true
spring:
jpa:
properties:
"[hibernate.generate_statistics]": true
7.3.17. Spring Data Repository Metrics
Auto-configuration enables the instrumentation of all Spring Data Repository
method invocations.
By default, metrics are generated with the name, spring.data.repository.invocations
.
You can customize the name by setting the management.metrics.data.repository.metric-name
property.
The @Timed
annotation from the io.micrometer.core.annotation
package is supported on Repository
interfaces and methods.
If you do not want to record metrics for all Repository
invocations, you can set management.metrics.data.repository.autotime.enabled
to false
and exclusively use @Timed
annotations instead.
A @Timed annotation with longTask = true enables a long task timer for the method.
Long task timers require a separate metric name and can be stacked with a short task timer.
|
By default, repository invocation related metrics are tagged with the following information:
Tag | Description |
---|---|
|
The simple class name of the source |
|
The name of the |
|
The result state ( |
|
The simple class name of any exception that was thrown from the invocation. |
To replace the default tags, provide a @Bean
that implements RepositoryTagsProvider
.
7.3.18. RabbitMQ Metrics
Auto-configuration enables the instrumentation of all available RabbitMQ connection factories with a metric named rabbitmq
.
7.3.19. Spring Integration Metrics
Spring Integration automatically provides Micrometer support whenever a MeterRegistry
bean is available.
Metrics are published under the spring.integration.
meter name.
7.3.20. Kafka Metrics
Auto-configuration registers a MicrometerConsumerListener
and MicrometerProducerListener
for the auto-configured consumer factory and producer factory, respectively.
It also registers a KafkaStreamsMicrometerListener
for StreamsBuilderFactoryBean
.
For more detail, see the Micrometer Native Metrics section of the Spring Kafka documentation.
7.3.21. MongoDB Metrics
This section briefly describes the available metrics for MongoDB.
MongoDB Command Metrics
Auto-configuration registers a MongoMetricsCommandListener
with the auto-configured MongoClient
.
A timer metric named mongodb.driver.commands
is created for each command issued to the underlying MongoDB driver.
Each metric is tagged with the following information by default:
Tag | Description |
---|---|
|
The name of the command issued. |
|
The identifier of the cluster to which the command was sent. |
|
The address of the server to which the command was sent. |
|
The outcome of the command ( |
To replace the default metric tags, define a MongoCommandTagsProvider
bean, as the following example shows:
@Configuration(proxyBeanMethods = false)
public class MyCommandTagsProviderConfiguration {
@Bean
public MongoCommandTagsProvider customCommandTagsProvider() {
return new CustomCommandTagsProvider();
}
}
@Configuration(proxyBeanMethods = false)
class MyCommandTagsProviderConfiguration {
@Bean
fun customCommandTagsProvider(): MongoCommandTagsProvider? {
return CustomCommandTagsProvider()
}
}
To disable the auto-configured command metrics, set the following property:
management.metrics.mongo.command.enabled=false
management:
metrics:
mongo:
command:
enabled: false
MongoDB Connection Pool Metrics
Auto-configuration registers a MongoMetricsConnectionPoolListener
with the auto-configured MongoClient
.
The following gauge metrics are created for the connection pool:
-
mongodb.driver.pool.size
reports the current size of the connection pool, including idle and and in-use members. -
mongodb.driver.pool.checkedout
reports the count of connections that are currently in use. -
mongodb.driver.pool.waitqueuesize
reports the current size of the wait queue for a connection from the pool.
Each metric is tagged with the following information by default:
Tag | Description |
---|---|
|
The identifier of the cluster to which the connection pool corresponds. |
|
The address of the server to which the connection pool corresponds. |
To replace the default metric tags, define a MongoConnectionPoolTagsProvider
bean:
@Configuration(proxyBeanMethods = false)
public class MyConnectionPoolTagsProviderConfiguration {
@Bean
public MongoConnectionPoolTagsProvider customConnectionPoolTagsProvider() {
return new CustomConnectionPoolTagsProvider();
}
}
@Configuration(proxyBeanMethods = false)
class MyConnectionPoolTagsProviderConfiguration {
@Bean
fun customConnectionPoolTagsProvider(): MongoConnectionPoolTagsProvider {
return CustomConnectionPoolTagsProvider()
}
}
To disable the auto-configured connection pool metrics, set the following property:
management.metrics.mongo.connectionpool.enabled=false
management:
metrics:
mongo:
connectionpool:
enabled: false
7.3.22. Jetty Metrics
Auto-configuration binds metrics for Jetty’s ThreadPool
by using Micrometer’s JettyServerThreadPoolMetrics
.
Metrics for Jetty’s Connector
instances are bound by using Micrometer’s JettyConnectionMetrics
and, when server.ssl.enabled
is set to true
, Micrometer’s JettySslHandshakeMetrics
.
7.3.23. @Timed Annotation Support
To use @Timed
where it is not directly supported by Spring Boot, refer to the Micrometer documentation.
7.3.24. Redis Metrics
Auto-configuration registers a MicrometerCommandLatencyRecorder
for the auto-configured LettuceConnectionFactory
.
For more detail, see the Micrometer Metrics section of the Lettuce documentation.
7.4. Registering Custom Metrics
To register custom metrics, inject MeterRegistry
into your component:
@Component
public class MyBean {
private final Dictionary dictionary;
public MyBean(MeterRegistry registry) {
this.dictionary = Dictionary.load();
registry.gauge("dictionary.size", Tags.empty(), this.dictionary.getWords().size());
}
}
@Component
class MyBean(registry: MeterRegistry) {
private val dictionary: Dictionary
init {
dictionary = Dictionary.load()
registry.gauge("dictionary.size", Tags.empty(), dictionary.words.size)
}
}
If your metrics depend on other beans, we recommend that you use a MeterBinder
to register them:
public class MyMeterBinderConfiguration {
@Bean
public MeterBinder queueSize(Queue queue) {
return (registry) -> Gauge.builder("queueSize", queue::size).register(registry);
}
}
class MyMeterBinderConfiguration {
@Bean
fun queueSize(queue: Queue): MeterBinder {
return MeterBinder { registry ->
Gauge.builder("queueSize", queue::size).register(registry)
}
}
}
Using a MeterBinder
ensures that the correct dependency relationships are set up and that the bean is available when the metric’s value is retrieved.
A MeterBinder
implementation can also be useful if you find that you repeatedly instrument a suite of metrics across components or applications.
By default, metrics from all MeterBinder beans are automatically bound to the Spring-managed MeterRegistry .
|
7.5. Customizing Individual Metrics
If you need to apply customizations to specific Meter
instances, you can use the io.micrometer.core.instrument.config.MeterFilter
interface.
For example, if you want to rename the mytag.region
tag to mytag.area
for all meter IDs beginning with com.example
, you can do the following:
@Configuration(proxyBeanMethods = false)
public class MyMetricsFilterConfiguration {
@Bean
public MeterFilter renameRegionTagMeterFilter() {
return MeterFilter.renameTag("com.example", "mytag.region", "mytag.area");
}
}
@Configuration(proxyBeanMethods = false)
class MyMetricsFilterConfiguration {
@Bean
fun renameRegionTagMeterFilter(): MeterFilter {
return MeterFilter.renameTag("com.example", "mytag.region", "mytag.area")
}
}
By default, all MeterFilter beans are automatically bound to the Spring-managed MeterRegistry .
Make sure to register your metrics by using the Spring-managed MeterRegistry and not any of the static methods on Metrics .
These use the global registry that is not Spring-managed.
|
7.5.1. Common Tags
You can configure common tags using the management.observations.key-values
property.
The order of common tags is important if you use Graphite.
As the order of common tags cannot be guaranteed by using this approach, Graphite users are advised to define a custom MeterFilter instead.
|
7.5.2. Per-meter Properties
In addition to MeterFilter
beans, you can apply a limited set of customization on a per-meter basis using properties.
Per-meter customizations are applied, using Spring Boot’s PropertiesMeterFilter
, to any meter IDs that start with the given name.
The following example filters out any meters that have an ID starting with example.remote
.
management.metrics.enable.example.remote=false
management:
metrics:
enable:
example:
remote: false
The following properties allow per-meter customization:
Property | Description |
---|---|
|
Whether to accept meters with certain IDs.
Meters that are not accepted are filtered from the |
|
Whether to publish a histogram suitable for computing aggregable (across dimension) percentile approximations. |
|
Publish fewer histogram buckets by clamping the range of expected values. |
|
Publish percentile values computed in your application |
|
Give greater weight to recent samples by accumulating them in ring buffers which rotate after a configurable expiry, with a configurable buffer length. |
|
Publish a cumulative histogram with buckets defined by your service-level objectives. |
For more details on the concepts behind percentiles-histogram
, percentiles
, and slo
, see the “Histograms and percentiles” section of the Micrometer documentation.
7.6. Metrics Endpoint
Spring Boot provides a metrics
endpoint that you can use diagnostically to examine the metrics collected by an application.
The endpoint is not available by default and must be exposed.
See exposing endpoints for more details.
Navigating to /actuator/metrics
displays a list of available meter names.
You can drill down to view information about a particular meter by providing its name as a selector — for example, /actuator/metrics/jvm.memory.max
.
The name you use here should match the name used in the code, not the name after it has been naming-convention normalized for a monitoring system to which it is shipped.
In other words, if |
You can also add any number of tag=KEY:VALUE
query parameters to the end of the URL to dimensionally drill down on a meter — for example, /actuator/metrics/jvm.memory.max?tag=area:nonheap
.
The reported measurements are the sum of the statistics of all meters that match the meter name and any tags that have been applied.
In the preceding example, the returned |
8. Tracing
Spring Boot Actuator provides dependency management and auto-configuration for Micrometer Tracing, a facade for popular tracer libraries.
To learn more about Micrometer Tracing capabilities, see its reference documentation. |
8.1. Supported Tracers
Spring Boot ships auto-configuration for the following tracers:
-
OpenTelemetry with Zipkin, Wavefront, or OTLP
-
OpenZipkin Brave with Zipkin or Wavefront
8.2. Getting Started
We need an example application that we can use to get started with tracing. For our purposes, the simple “Hello World!” web application that’s covered in the “getting-started.html” section will suffice. We’re going to use the OpenTelemetry tracer with Zipkin as trace backend.
To recap, our main application code looks like this:
@RestController
@SpringBootApplication
public class MyApplication {
private static final Log logger = LogFactory.getLog(MyApplication.class);
@RequestMapping("/")
String home() {
logger.info("home() has been called");
return "Hello World!";
}
public static void main(String[] args) {
SpringApplication.run(MyApplication.class, args);
}
}
There’s an added logger statement in the home() method, which will be important later.
|
Now we have to add the following dependencies:
-
org.springframework.boot:spring-boot-starter-actuator
-
io.micrometer:micrometer-tracing-bridge-otel
- bridges the Micrometer Observation API to OpenTelemetry. -
io.opentelemetry:opentelemetry-exporter-zipkin
- reports traces to Zipkin.
Add the following application properties:
management.tracing.sampling.probability=1.0
management:
tracing:
sampling:
probability: 1.0
By default, Spring Boot samples only 10% of requests to prevent overwhelming the trace backend. This property switches it to 100% so that every request is sent to the trace backend.
To collect and visualize the traces, we need a running trace backend. We use Zipkin as our trace backend here. The Zipkin Quickstart guide provides instructions how to start Zipkin locally.
After Zipkin is running, you can start your application.
If you open a web browser to localhost:8080
, you should see the following output:
Hello World!
Behind the scenes, an observation has been created for the HTTP request, which in turn gets bridged to OpenTelemetry, which reports a new trace to Zipkin.
Now open the Zipkin UI at localhost:9411
and press the "Run Query" button to list all collected traces.
You should see one trace.
Press the "Show" button to see the details of that trace.
8.3. Logging Correlation IDs
Correlation IDs provide a helpful way to link lines in your log files to spans/traces.
By default, as long as management.tracing.enabled
has not been set to false
, Spring Boot will include correlation IDs in your logs whenever you are using Micrometer Tracing.
The default correlation ID is built from traceId
and spanId
MDC values.
For example, if Micrometer Tracing has added an MDC traceId
of 803B448A0489F84084905D3093480352
and an MDC spanId
of 3425F23BB2432450
the log output will include the correlation ID [803B448A0489F84084905D3093480352-3425F23BB2432450]
.
If you prefer to use a different format for your correlation ID, you can use the logging.pattern.correlation
property to define one.
For example, the following will provide a correlation ID for Logback in format previously used by Spring Cloud Sleuth:
logging.pattern.correlation=[${spring.application.name:},%X{traceId:-},%X{spanId:-}]
logging.include-application-name=false
logging:
pattern:
correlation: "[${spring.application.name:},%X{traceId:-},%X{spanId:-}] "
include-application-name: false
In the example above, logging.include-application-name is set to false to avoid the application name being duplicated in the log messages (logging.pattern.correlation already contains it).
It’s also worth mentioning that logging.pattern.correlation contains a trailing space so that it is separated from the logger name that comes right after it by default.
|
8.4. Propagating Traces
To automatically propagate traces over the network, use the auto-configured RestTemplateBuilder
or WebClient.Builder
to construct the client.
If you create the WebClient or the RestTemplate without using the auto-configured builders, automatic trace propagation won’t work!
|
8.5. Tracer Implementations
As Micrometer Tracer supports multiple tracer implementations, there are multiple dependency combinations possible with Spring Boot.
All tracer implementations need the org.springframework.boot:spring-boot-starter-actuator
dependency.
8.5.1. OpenTelemetry With Zipkin
Tracing with OpenTelemetry and reporting to Zipkin requires the following dependencies:
-
io.micrometer:micrometer-tracing-bridge-otel
- bridges the Micrometer Observation API to OpenTelemetry. -
io.opentelemetry:opentelemetry-exporter-zipkin
- reports traces to Zipkin.
Use the management.zipkin.tracing.*
configuration properties to configure reporting to Zipkin.
8.5.2. OpenTelemetry With Wavefront
Tracing with OpenTelemetry and reporting to Wavefront requires the following dependencies:
-
io.micrometer:micrometer-tracing-bridge-otel
- bridges the Micrometer Observation API to OpenTelemetry. -
io.micrometer:micrometer-tracing-reporter-wavefront
- reports traces to Wavefront.
Use the management.wavefront.*
configuration properties to configure reporting to Wavefront.
8.5.3. OpenTelemetry With OTLP
Tracing with OpenTelemetry and reporting using OTLP requires the following dependencies:
-
io.micrometer:micrometer-tracing-bridge-otel
- bridges the Micrometer Observation API to OpenTelemetry. -
io.opentelemetry:opentelemetry-exporter-otlp
- reports traces to a collector that can accept OTLP.
Use the management.otlp.tracing.*
configuration properties to configure reporting using OTLP.
8.5.4. OpenZipkin Brave With Zipkin
Tracing with OpenZipkin Brave and reporting to Zipkin requires the following dependencies:
-
io.micrometer:micrometer-tracing-bridge-brave
- bridges the Micrometer Observation API to Brave. -
io.zipkin.reporter2:zipkin-reporter-brave
- reports traces to Zipkin.
If your project doesn’t use Spring MVC or Spring WebFlux, the io.zipkin.reporter2:zipkin-sender-urlconnection dependency is needed, too.
|
Use the management.zipkin.tracing.*
configuration properties to configure reporting to Zipkin.
8.5.5. OpenZipkin Brave With Wavefront
Tracing with OpenZipkin Brave and reporting to Wavefront requires the following dependencies:
-
io.micrometer:micrometer-tracing-bridge-brave
- bridges the Micrometer Observation API to Brave. -
io.micrometer:micrometer-tracing-reporter-wavefront
- reports traces to Wavefront.
Use the management.wavefront.*
configuration properties to configure reporting to Wavefront.
8.6. Integration with Micrometer Observation
A TracingAwareMeterObservationHandler
is automatically registered on the ObservationRegistry
, which creates spans for every completed observation.
8.7. Creating Custom Spans
You can create your own spans by starting an observation.
For this, inject ObservationRegistry
into your component:
@Component
class CustomObservation {
private final ObservationRegistry observationRegistry;
CustomObservation(ObservationRegistry observationRegistry) {
this.observationRegistry = observationRegistry;
}
void someOperation() {
Observation observation = Observation.createNotStarted("some-operation", this.observationRegistry);
observation.lowCardinalityKeyValue("some-tag", "some-value");
observation.observe(() -> {
// Business logic ...
});
}
}
This will create an observation named "some-operation" with the tag "some-tag=some-value".
If you want to create a span without creating a metric, you need to use the lower-level Tracer API from Micrometer.
|
8.8. Baggage
You can create baggage with the Tracer
API:
@Component
class CreatingBaggage {
private final Tracer tracer;
CreatingBaggage(Tracer tracer) {
this.tracer = tracer;
}
void doSomething() {
try (BaggageInScope scope = this.tracer.createBaggageInScope("baggage1", "value1")) {
// Business logic
}
}
}
This example creates baggage named baggage1
with the value value1
.
The baggage is automatically propagated over the network if you’re using W3C propagation.
If you’re using B3 propagation, baggage is not automatically propagated.
To manually propagate baggage over the network, use the management.tracing.baggage.remote-fields
configuration property (this works for W3C, too).
For the example above, setting this property to baggage1
results in an HTTP header baggage1: value1
.
If you want to propagate the baggage to the MDC, use the management.tracing.baggage.correlation.fields
configuration property.
For the example above, setting this property to baggage1
results in an MDC entry named baggage1
.
8.9. Tests
Tracing components which are reporting data are not auto-configured when using @SpringBootTest
.
See the testing section for more details.
9. 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.
You can enable auditing by providing a bean of type AuditEventRepository
in your application’s configuration.
For convenience, Spring Boot offers an InMemoryAuditEventRepository
.
InMemoryAuditEventRepository
has limited capabilities, and we recommend using it only for development environments.
For production environments, consider creating your own alternative AuditEventRepository
implementation.
9.1. Custom Auditing
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 AuditEventRepository
bean into your own components and use that directly or publish an AuditApplicationEvent
with the Spring ApplicationEventPublisher
(by implementing ApplicationEventPublisherAware
).
10. Recording HTTP Exchanges
You can enable recording of HTTP exchanges by providing a bean of type HttpExchangeRepository
in your application’s configuration.
For convenience, Spring Boot offers InMemoryHttpExchangeRepository
, which, by default, stores the last 100 request-response exchanges.
InMemoryHttpExchangeRepository
is limited compared to tracing solutions, and we recommend using it only for development environments.
For production environments, we recommend using a production-ready tracing or observability solution, such as Zipkin or OpenTelemetry.
Alternatively, you can create your own HttpExchangeRepository
.
You can use the httpexchanges
endpoint to obtain information about the request-response exchanges that are stored in the HttpExchangeRepository
.
11. 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 that contains the application PID (by default, in the application directory with a file name ofapplication.pid
). -
WebServerPortFileWriter
creates a file (or files) that contain the ports of the running web server (by default, in the application directory with a file name ofapplication.port
).
By default, these writers are not activated, but you can enable them:
11.1. Extending Configuration
In the META-INF/spring.factories
file, you can activate the listener (or listeners) that writes a PID file:
org.springframework.context.ApplicationListener=\ org.springframework.boot.context.ApplicationPidFileWriter,\ org.springframework.boot.web.context.WebServerPortFileWriter
12. 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 can include full health information instead of the typical “running” or “stopped” status.
The /cloudfoundryapplication path is not directly accessible to regular users.
To use the endpoint, you must pass a valid UAA token with the request.
|
12.1. 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:
management.cloudfoundry.enabled=false
management:
cloudfoundry:
enabled: false
12.2. 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:
management.cloudfoundry.skip-ssl-validation=true
management:
cloudfoundry:
skip-ssl-validation: true
12.3. Custom Context Path
If the server’s context-path has been configured to anything other than /
, the Cloud Foundry endpoints are not available at the root of the application.
For example, if server.servlet.context-path=/app
, Cloud Foundry endpoints are available at /app/cloudfoundryapplication/*
.
If you expect the Cloud Foundry endpoints to always be available at /cloudfoundryapplication/*
, regardless of the server’s context-path, you need to explicitly configure that in your application.
The configuration differs, depending on the web server in use.
For Tomcat, you can add the following configuration:
@Configuration(proxyBeanMethods = false)
public class MyCloudFoundryConfiguration {
@Bean
public TomcatServletWebServerFactory servletWebServerFactory() {
return new TomcatServletWebServerFactory() {
@Override
protected void prepareContext(Host host, ServletContextInitializer[] initializers) {
super.prepareContext(host, initializers);
StandardContext child = new StandardContext();
child.addLifecycleListener(new Tomcat.FixContextListener());
child.setPath("/cloudfoundryapplication");
ServletContainerInitializer initializer = getServletContextInitializer(getContextPath());
child.addServletContainerInitializer(initializer, Collections.emptySet());
child.setCrossContext(true);
host.addChild(child);
}
};
}
private ServletContainerInitializer getServletContextInitializer(String contextPath) {
return (classes, context) -> {
Servlet servlet = new GenericServlet() {
@Override
public void service(ServletRequest req, ServletResponse res) throws ServletException, IOException {
ServletContext context = req.getServletContext().getContext(contextPath);
context.getRequestDispatcher("/cloudfoundryapplication").forward(req, res);
}
};
context.addServlet("cloudfoundry", servlet).addMapping("/*");
};
}
}
@Configuration(proxyBeanMethods = false)
class MyCloudFoundryConfiguration {
@Bean
fun servletWebServerFactory(): TomcatServletWebServerFactory {
return object : TomcatServletWebServerFactory() {
override fun prepareContext(host: Host, initializers: Array<ServletContextInitializer>) {
super.prepareContext(host, initializers)
val child = StandardContext()
child.addLifecycleListener(FixContextListener())
child.path = "/cloudfoundryapplication"
val initializer = getServletContextInitializer(contextPath)
child.addServletContainerInitializer(initializer, emptySet())
child.crossContext = true
host.addChild(child)
}
}
}
private fun getServletContextInitializer(contextPath: String): ServletContainerInitializer {
return ServletContainerInitializer { classes: Set<Class<*>?>?, context: ServletContext ->
val servlet: Servlet = object : GenericServlet() {
@Throws(ServletException::class, IOException::class)
override fun service(req: ServletRequest, res: ServletResponse) {
val servletContext = req.servletContext.getContext(contextPath)
servletContext.getRequestDispatcher("/cloudfoundryapplication").forward(req, res)
}
}
context.addServlet("cloudfoundry", servlet).addMapping("/*")
}
}
}
If you’re using a Webflux based application, you can use the following configuration:
@Configuration(proxyBeanMethods = false)
@EnableConfigurationProperties(WebFluxProperties.class)
public class MyReactiveCloudFoundryConfiguration {
@Bean
public HttpHandler httpHandler(ApplicationContext applicationContext, WebFluxProperties properties) {
HttpHandler httpHandler = WebHttpHandlerBuilder.applicationContext(applicationContext).build();
return new CloudFoundryHttpHandler(properties.getBasePath(), httpHandler);
}
private static final class CloudFoundryHttpHandler implements HttpHandler {
private final HttpHandler delegate;
private final ContextPathCompositeHandler contextPathDelegate;
private CloudFoundryHttpHandler(String basePath, HttpHandler delegate) {
this.delegate = delegate;
this.contextPathDelegate = new ContextPathCompositeHandler(Map.of(basePath, delegate));
}
@Override
public Mono<Void> handle(ServerHttpRequest request, ServerHttpResponse response) {
// Remove underlying context path first (e.g. Servlet container)
String path = request.getPath().pathWithinApplication().value();
if (path.startsWith("/cloudfoundryapplication")) {
return this.delegate.handle(request, response);
}
else {
return this.contextPathDelegate.handle(request, response);
}
}
}
}
@Configuration(proxyBeanMethods = false)
@EnableConfigurationProperties(WebFluxProperties::class)
class MyReactiveCloudFoundryConfiguration {
@Bean
fun httpHandler(applicationContext: ApplicationContext, properties: WebFluxProperties): HttpHandler {
val httpHandler = WebHttpHandlerBuilder.applicationContext(applicationContext).build()
return CloudFoundryHttpHandler(properties.basePath, httpHandler)
}
private class CloudFoundryHttpHandler(basePath: String, private val delegate: HttpHandler) : HttpHandler {
private val contextPathDelegate = ContextPathCompositeHandler(mapOf(basePath to delegate))
override fun handle(request: ServerHttpRequest, response: ServerHttpResponse): Mono<Void> {
// Remove underlying context path first (e.g. Servlet container)
val path = request.path.pathWithinApplication().value()
return if (path.startsWith("/cloudfoundryapplication")) {
delegate.handle(request, response)
} else {
contextPathDelegate.handle(request, response)
}
}
}
}
13. What to Read Next
You might want to read about graphing tools such as Graphite.
Otherwise, you can continue on to read about “deployment options” or jump ahead for some in-depth information about Spring Boot’s build tool plugins.