Spring Boot Profiles

Spring Boot profiles are used to separate configuration and behavior for different environments such as dev, test, qa, and prod.

Profiles help you run the same application code in multiple environments without changing the code itself.

Why Profiles Are Needed (Very Important)

In real applications, environments differ in:

Database URLs
Credentials
Logging levels
Caching
External system endpoints

Without profiles:

You hardcode values ❌
You manually change config ❌
You risk deploying wrong settings ❌

Profiles solve environment-specific configuration cleanly and safely.

What Is a Profile?

A profile is a named logical group of configuration.

Examples:

dev
test
qa
prod

Spring activates one or more profiles at runtime.

How Profiles Work (High Level)

Spring:

Loads default configuration
Loads profile-specific configuration
Overrides matching properties
Creates beans conditionally

Profile-specific config overrides default config.

application.properties vs application-{profile}.properties

Default Configuration

application.properties

Used when:

No profile is active
Or as base configuration

Profile-Specific Configuration

application-dev.properties
application-test.properties
application-prod.properties

Spring loads:

application.properties
PLUS active profile file

Example

application.properties

server.port=8080
logging.level.root=INFO

application-dev.properties

server.port=8081
logging.level.root=DEBUG
spring.datasource.url=jdbc:h2:mem:testdb

application-prod.properties

server.port=8080
logging.level.root=ERROR
spring.datasource.url=jdbc:postgresql://prod-db:5432/app

How to Activate a Profile

1️⃣ Using application.properties

spring.profiles.active=dev

❌ Not recommended for prod (hardcoded)

2️⃣ Using JVM Argument (MOST COMMON)

-Dspring.profiles.active=prod

✔ Preferred
✔ Environment controlled

3️⃣ Using Command Line

--spring.profiles.active=dev

Using @Profile on Beans

Profiles can control bean creation.

Example

@Component
@Profile("dev")
public class DevEmailService implements EmailService {
}

@Component
@Profile("prod")
public class ProdEmailService implements EmailService {
}

Only one bean is created based on active profile.

Multiple Profiles Active

Spring allows multiple active profiles.

SPRING_PROFILES_ACTIVE=dev,local

Use cases:

dev + local
prod + cloud

@Profile with @Configuration

@Configuration
@Profile("test")
public class TestConfig {
}

Entire configuration class is profile-specific.

Default Profile

If no profile is active:

Spring uses default profile
Name: default

You can also define:

spring.profiles.default=dev

Profile Groups (Spring Boot Feature)

Profiles can be grouped.

spring.profiles.group.prod=prod,cloud,monitoring

Activating prod activates all grouped profiles.

Summary

Profiles separate environment configuration
application-{profile}.properties overrides defaults
Activated via env variable or JVM arg
@Profile controls bean creation
Multiple profiles can be active
Default profile exists