Spring Boot Profiles with examples

In this tutorial, we are going to look at spring boot profiles and what is the use of it?

Profiles are the core feature of spring boot framework that provides a way to segregate parts of your application configuration and make it available only in a certain environment.

It is highly useful when configuring a different environment like prod, dev, test, etc.

What is the use of profiles in Spring?

Before I demonstrate how to manage spring profiles, let’s take a look where spring profiles are useful?

Let’s take an example of an e-commerce application.

In a real e-commerce application, there could be millions of products stored in the database.

So, how you can ensure that while adding features or while doing testing there won’t be any modification of existing data.

Here spring profiles are extremely useful.

By using spring profiles you can set different environments like production (prod), development (dev) and testing.

And you can set different database with dummy values for dev and testing environment.

You can also set different configuration properties like server port, data source, AdSense publisher id for different environments.

Let’s understand spring profiles using a demo project.

How to create environment profiles

There are two ways to create Profiles. Let’s take a look at both of them.

Create a Spring boot profile by using the yml file.

To create a profile using yml, you can go to main->resources and create two files application-dev.yml for dev environment and application-test.yml for test environment

Now let’s set up a default server port in the application.properties file

server.port=9000

Let’s make some changes in application-dev.yml and application-test.yml to change port details for both dev and test environment.

# application-dev.yml

server:
     port: 8090

# application-test.yml

server:
    port: 7070

As you can see in the above code, our application will use the 8090 port when the dev environment is active however it will use 7070 port if the test environment is active.

On the contrary, what will happen when no specific environment is active?

Then the application will run in the 9000 port which is default specified in application.properties.

Logs when ‘dev’ profile was active

2019-07-22 23:47:42.444  INFO 14324 - – [           main] c.c.p.SpringbootProfilesDemoApplication  : The following profiles are active: dev
 2019-07-22 23:47:44.355  INFO 14324 - – [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8090 (http)

When ‘test’ profile was active

2019-07-22 23:49:06.967  INFO 18604 - – [           main] c.c.p.SpringbootProfilesDemoApplication  : The following profiles are active: test
2019-07-22 23:49:08.756  INFO 18604 - – [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 7070 (http)

Logs when the ‘dev’ profile was active

2019-07-22 23:50:05.854  INFO 17820 - – [           main] c.c.p.SpringbootProfilesDemoApplication  : No active profile set, falling back to default profiles: default
2019-07-22 23:50:07.692  INFO 17820 - – [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 9000 (http)

Use @Profile on a configuration class.

If you want spring container to process configuration class or any bean class (service/component/repositories) only if a particular profile is active then you can use @Profile annotation.

Let’s have a look at below TestConfigProfile class

package com.codedelay.profiles;

import javax.annotation.PostConstruct;

import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Profile;

@Profile("test")
@Configuration
public class TestConfigProfile {

	@PostConstruct
	public void onLoadTestEnvironment() {
		System.out.println("Test environment loaded");
	}
}

The spring container will process the above class only if the ‘test’ profile is active.

Scenario -1 When the ‘dev’ profile is active.

2019-07-22 23:42:08.847  INFO 17128 - – [           main] c.c.p.SpringbootProfilesDemoApplication  : The following profiles are active: dev

Scenario – 2 When the ‘test’ profile is active.

2019-07-22 23:43:31.029  INFO 13372 - – [           main] c.c.p.SpringbootProfilesDemoApplication  : The following profiles are active: test
2019-07-22 23:43:33.097  INFO 13372 - – [           main] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 1999 ms
Test environment loaded

As you could see in the above example, when the ‘test’ profile was active, then only spring container processed TestConfigProfile and log 'Test environment loaded' was printed to the console.

How to activate a Profile

There are multiple ways to activate a profile. Let’s take a look at them one by one.

New environment variable in the run configuration

This is the most convenient way to activate a profile.

To activate a profile you can create a new environment variable spring.profiles.active in the Environment tab. and provide the value ‘dev’.

VM Arguments

You can also provide VM arguments in the run configuration to activate a profile. As you could see below logs, the same profile ‘dev’ activated during application start up.

2019-07-23 06:36:02.333  INFO 20376 - – [           main] c.c.p.SpringbootProfilesDemoApplication  : The following profiles are active: dev
2019-07-23 06:36:04.376  INFO 20376 - – [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8090 (http)

Conclusion

In this tutorial, we discussed how to set up and activate profiles in Spring boot. Also, I’ve demonstrated the spring profiles concept using a few real-world examples. In case of any doubts, you can ask me anything in the comments section.

Arpit