Spring Boot Actuator

Spring Boot Actuator provides production-ready features to monitor and manage your applications. This guide explores Actuator's capabilities, how to enable it, and secure its endpoints.

🌟 Why Use Spring Boot Actuator?

Spring Boot Actuator allows developers to:

• Monitor application health
• Gather metrics and information
• Expose management endpoints for operational tasks

🌟 Prerequisites

📋 Ensure you have the following:

• ☕ Java Development Kit (JDK) 17+
• 💼 Maven or Gradle installed
• 🄄 A Java IDE (e.g., IntelliJ IDEA, Eclipse)

🛠️ Step 1: Add Dependencies

To enable Actuator, add the following dependency to your Spring Boot project:

• Maven:

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

• Gradle:

implementation 'org.springframework.boot:spring-boot-starter-actuator'

📜 Step 2: Enable Actuator Endpoints

By default, Actuator exposes several endpoints to provide application insights. You can enable these endpoints in your application.properties or application.yml file.

Configuration Example:

management.endpoints.web.exposure.include=health,info,metrics
management.endpoint.health.show-details=always

📖 Step 3: Using Actuator Endpoints

Here are some commonly used Actuator endpoints:

• /actuator/health: Provides application health status.
• /actuator/info: Displays application metadata.
• /actuator/metrics: Offers application performance metrics.

You can access these endpoints via a browser or API tools like cURL.

Example:

curl -X GET http://localhost:8080/actuator/health

📘 Step 4: Customize Actuator Endpoints

You can customize Actuator endpoints to suit your needs. For example, you can define additional metadata in the application.properties file for the /actuator/info endpoint:

info.app.name=My Application
info.app.version=1.0.0
info.app.description=Spring Boot Actuator Example

🔒 Step 5: Secure Actuator Endpoints

For production environments, it's essential to secure Actuator endpoints. Use Spring Security to restrict access.

• Java
• Kotlin

package com.example.demo.config;

import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.web.SecurityFilterChain;

@Configuration
public class SecurityConfig {

    public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
        http
            .authorizeHttpRequests()
                .requestMatchers("/actuator/**").hasRole("ADMIN")
                .anyRequest().authenticated()
            .and()
            .httpBasic();
        return http.build();
    }
}

package com.example.demo.config

import org.springframework.context.annotation.Bean
import org.springframework.context.annotation.Configuration
import org.springframework.security.config.annotation.web.builders.HttpSecurity
import org.springframework.security.web.SecurityFilterChain

@Configuration
class SecurityConfig {

    @Bean
    fun securityFilterChain(http: HttpSecurity): SecurityFilterChain {
        http
            .authorizeHttpRequests()
                .requestMatchers("/actuator/**").hasRole("ADMIN")
                .anyRequest().authenticated()
            .and()
            .httpBasic()
        return http.build()
    }
}

▶️ Running the Application

Run the application using the following command:

./mvnw spring-boot:run

Access the Actuator endpoints at:

http://localhost:8080/actuator/health

🧪 Test the API

You can test the Actuator endpoints using cURL or browser:

• Health Endpoint:

curl -X GET http://localhost:8080/actuator/health

• Info Endpoint:

curl -X GET http://localhost:8080/actuator/info

Spring Boot Actuator simplifies monitoring and managing your application. This guide covered enabling, customizing, and securing Actuator endpoints to improve your Spring Boot project.