Configuring Multiple Profiles in a Single YAML File for Spring Boot Application

Spring Boot provides a convenient way to configure application properties using YAML files. In a typical scenario, you might have different configurations for different environments such as development, testing, and production. Instead of maintaining multiple YAML files for each profile, you can configure multiple profiles within a single YAML file. This approach simplifies the configuration management process. Let's see how to achieve this.

Step 1: Create a YAML Configuration File

First, create a YAML file (e.g., application.yml) in your Spring Boot project's resource directory. This file will contain the configuration properties for all the profiles you want to define.

spring:
  profiles:
    active: dev

logging:
  level:
    root: INFO
    com.example: DEBUG

# Configuration for the 'dev' profile
---
spring:
  profiles: dev

database:
  url: jdbc:mysql://localhost:3306/devdb
  username: devuser
  password: devpassword

# Configuration for the 'prod' profile
---
spring:
  profiles: prod

database:
  url: jdbc:mysql://localhost:3306/proddb
  username: produser
  password: prodpassword
  

In the above example, we have two profiles defined: dev and prod. The dev profile configures the database URL, username, and password for the development environment. Similarly, the prod profile configures these properties for the production environment.

Step 2: Activate a Specific Profile

By default, the dev profile is active as specified by spring.profiles.active property in the configuration file. You can change the active profile by setting the environment variable SPRING_PROFILES_ACTIVE to the desired profile name.

Step 3: Access Profile-Specific Properties

In your Spring Boot application, you can access the profile-specific properties using the @Value annotation or the @ConfigurationProperties annotation.

Using @Value Annotation

import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

@Component
public class MyComponent {

  @Value("${database.url}")
  private String databaseUrl;

  @Value("${database.username}")
  private String databaseUsername;

  @Value("${database.password}")
  private String databasePassword;

  // ...
}
  

Using @ConfigurationProperties Annotation

import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;

@Component
@ConfigurationProperties("database")
public class DatabaseProperties {

  private String url;
  private String username;
  private String password;

  // Getters and setters

  // ...
}
  

With the above configuration, you can inject the DatabaseProperties bean into your components and access the profile-specific properties using its getters.

Configuring multiple profiles in a single YAML file simplifies the management of configuration properties for different environments in a Spring Boot application. You can define profile-specific properties in the same file and easily switch between profiles using the spring.profiles.active property or environment variables.