SpringBoot Actuator Kullanımı

Giriş
Actuator projesi Application Performance Monitoring işlemi içindir. Bu işlemin amacı şöyle.

I think you could broadly define it as anything that has to do with monitoring the performance of a website or application. For example, there are tools that do nothing but check your website every minute to see if it is online and how long it takes to load. I guess you could say this is the absolute simplest form of application performance monitoring.

Application Performance Management (APM) ise biraz daha farklı. Bu işlemin amacı şöyle.

Most APM solutions automatically discover and help you track all of your applications across all environments. Including pre-production and production environments.

There are several things that development teams need to track and manage their applications:

- Application type (web, background service, etc).
- Installed locations and the number of server instances.
- Deployment history.
- Application availability/uptime (SLAs).
- Web application traffic/usage.
- Performance indicators (response times, satisfaction scores, etc).
- Error rates.

Tüm endpointleri görmek için şöyle yaparız

http://localhost:8080/actuator

Gözlemlenebilirlik - Observability
5 tane temel örüntü var. Actuator, Application Metrics kısmını sağlar.

Health-Check API
Distributed Tracing
Application Metrics
Exception Tracking
Audit Logging
Applicaton Logging

Actuator ve Security
Açıklaması şöyle.  /actuator/** adresi için istenilen ayar yapılır

There is no need to worry about security; if Spring Security is present, then these endpoints are secured by default using Spring Security’s content-negotiation strategy. Or else, we can configure custom security by the help of RequestMatcher.

Örnek

Eğer her şeye izin vermek istersek şöyle yaparız

@Bean
public SecurityFilterChain filterChain(HttpSecurity httpSecurity) throws Exception {
  // to keep things simple, API endpoints are permitted for all
  httpSecurity
    .headers().frameOptions().disable()
    .and()
    .csrf().disable()
    .authorizeRequests()
    .antMatchers("/v3/api-docs/**", "/swagger-ui/**", "/swagger-ui.html").permitAll()
    .antMatchers("/h2-console/**").permitAll()
    .antMatchers(HttpMethod.GET, "/actuator/health/**").permitAll()
    .anyRequest()
    .authenticated()
    .and()
    .httpBasic()
    .and()
    .sessionManagement()
    .sessionCreationPolicy(SessionCreationPolicy.STATELESS);

  return httpSecurity.build();
}

Örnek

Şöyle yaparız

@Bean
public SecurityWebFilterChain securityWebFilterChain(ServerHttpSecurity http) {
  return http.authorizeExchange()
    .pathMatchers("/actuator/**").permitAll()
    .anyExchange().authenticated()
    .and().build();
}

Metrikleri Loglamak
Açıklaması şöyle.

Metrics have to be stored somewhere. The most popular tools for that are InfluxDB and Prometheus. They are representing two different models of collecting data. Prometheus periodically retrieves data from endpoint exposed by the application, while InfluxDB provides REST API that has to be called by the application. The integration with those two tools and several other is realized with the Micrometer library.

Maven
Şu satırı dahil ederiz.

<dependency>
  <groupId> org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-actuator</artifactId>
</dependency>

Actuator'ı silmek için maven'dan spring-boot-starter-actuator satırı silinir. Açıklaması şöyle.

Enabling/disabling the actuator is easy; the simplest way is to enable features to add the dependency (Maven/Gradle) to the spring-boot-starter-actuator, i.e. Starter. If you don't want the actuator to be enabled, then don't add the dependency.

actuator Endpoint

Açıklaması şöyle

it will list down all the endpoints that are enabled and exposed.

Örnek bir çıktı şöyle

{
  "_links":{
    "self":{
      "href":"http://localhost:8080/actuator",
      "templated":false
    },
    "info":{
      "href":"http://localhost:8080/actuator/info",
      "templated":false
    },
    "env":{
      "href":"http://localhost:8080/actuator/env",
      "templated":false
    },
    "env-toMatch":{
      "href":"http://localhost:8080/actuator/env/{toMatch}",
      "templated":true
    }
  }
}

auditevents Endpoint

Açıklaması şöyle.

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.

beans Endpoint

beans Endpoint yazısına taşıdım

caches Endpoint

Açıklaması şöyle

Exposes available caches

env Endpoint

Açıklaması şöyle

Shows application environment information

health Endpoint

Health Endpoint yazısına taşıdım.

httptrace Endpoint

http trace Endpoint yazısına taşıdım

info Endpoint
Info Endpoint yazısına taşıdım

loggers Endpoint
Loggers Endpoint yazısına taşıdım.

mappings Endpoint

Açıklaması şöyle

Displays a list of all request mappings in the application.

metrics Endpoint

Metrics Endpoint yazısına taşıdım.

refresh Endpoint

SpringCloud Config Client yazısına bakabilirsiniz.

Örnek

Konfigürasyon ayarlarını tekrar okumak için şöyle yaparız.

curl localhost:8080/actuator/refresh -d {} -H "Content-Type: application/json

shutdown Endpoint
Shutdown Endpoint  yazısına taşıdım

startup Endpoint

Startup Endpoint yazısına taşıdım.

threaddump Endpoint

Açıklaması şöyle

Provides a thread dump of application.