Spring Profiles

1. Overview

In this article, we’ll focus on introducing Profiles in Spring.

Profiles are a core feature of the framework – allowing us to map our beans to different profiles – for example, dev, test, prod.

We can then activate different profiles in different environments to bootstrap just the beans we need:

Further reading:

Configuring Separate Spring DataSource for Tests

A quick, practical tutorial on how to configure a separate data source for testing in a Spring application.

Read more →

Properties with Spring and Spring Boot

Tutorial for how to work with properties files and property values in Spring.

Read more →

2. Use @Profile on a Bean

Let’s start simple and look at how we can make a bean belong to a particular profile. Using the @Profile annotation – we are mapping the bean to that particular profile; the annotation simply takes the names of one (or multiple) profiles.

Consider a basic scenario – we have a bean that should only be active during development, but not deployed in production. We annotate that bean with a “dev” profile, and it will only be present in the container during development – in production, the dev simply won’t be active:

@Component
@Profile("dev")
public class DevDatasourceConfig

As a quick sidenote, profile names can also be prefixed with a NOT operator e.g. “!dev” to exclude them from a profile.

In the below example, the component is activated only if “dev” profile is not active:

@Component
@Profile("!dev")
public class DevDatasourceConfig

3. Declare Profiles in XML

Profiles can also be configured in XML – the <beans> tag has “profiles” attribute which takes comma separated values of the applicable profiles:

<beans profile="dev">
    <bean id="devDatasourceConfig"
      class="org.baeldung.profiles.DevDatasourceConfig" />
</beans>

4. Set Profiles

The next step is to activate and set the profiles so that the respective beans are registered in the container.

This can be done in a variety of ways – which we’ll explore in the following sections.

4.1. Programmatically via WebApplicationInitializer Interface

In web applications, WebApplicationInitializer can be used to configure the ServletContext programmatically.

It’s also a very handy location to set our active profiles programmatically:

@Configuration
public class MyWebApplicationInitializer
  implements WebApplicationInitializer {

    @Override
    public void onStartup(ServletContext servletContext) throws ServletException {

        servletContext.setInitParameter(
          "spring.profiles.active", "dev");
    }
}

4.2. Programmatically via ConfigurableEnvironment

You can also set profiles directly on the environment:

@Autowired
private ConfigurableEnvironment env;
...
env.setActiveProfiles("someProfile");

4.3. Context Parameter in web.xml

Similarly, profiles can be activated in the web.xml of the web application as well, using a context parameter:

<context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>/WEB-INF/app-config.xml</param-value>
</context-param>
<context-param>
    <param-name>spring.profiles.active</param-name>
    <param-value>dev</param-value>
</context-param>

4.4. JVM System Parameter

The profile names can also be passed in via a JVM system parameter. The profile names passed as the parameter will be activated during application start-up:

-Dspring.profiles.active=dev

4.5. Environment Variable

In a Unix environment, profiles can also be activated via the environment variable:

export spring_profiles_active=dev

4.6. Maven Profile

Spring profiles can also be activated via Maven profiles, by specifying the spring.profiles.active configuration property.

In every Maven profile, we can set a spring.profiles.active property:

<profiles>
    <profile>
        <id>dev</id>
        <activation>
            <activeByDefault>true</activeByDefault>
        </activation>
        <properties>
            <spring.profiles.active>dev</spring.profiles.active>
        </properties>
    </profile>
    <profile>
        <id>prod</id>
        <properties>
            <spring.profiles.active>prod</spring.profiles.active>
        </properties>
    </profile>
</profiles>

Its value will be used to replace the @[email protected] placeholder in application.properties:

[email protected]@

Now, we need to enable resource filtering in pom.xml:

<build>
    <resources>
        <resource>
            <directory>src/main/resources</directory>
            <filtering>true</filtering>
        </resource>
    </resources>
    ...
</build>

And append a -P parameter to switch which Maven profile will be applied:

mvn clean package -Pprod

This command will package the application for prod profile. It also applies the spring.profiles.active value ‘prod’ for this application when it is running.

4.7. @ActiveProfile in Tests

Tests make it very easy to specify what profiles are active – using the @ActiveProfile annotation to enable specific profiles:

@ActiveProfiles("dev")

To summarize, we looked at multiple ways of activating profiles. Let’s now see which one has priority over the other and what happens if you use more than one – from highest to lowest priority:

  1. Context parameter in web.xml

  2. WebApplicationInitializer

  3. JVM System parameter

  4. Environment variable

  5. Maven profile

5. The Default Profile

Any bean that does not specify a profile belongs to “default” profile.

Spring also provides a way to set the default profile when no other profile is active – by using the “spring.profiles.default” property.

6. Get Active Profiles

Spring’s active profiles drive the behavior of the @Profile annotation for enabling/disabling beans. However, we may also wish to access the list of active profiles programmatically.

We have two ways to do it, using Environment or *spring.active.profile*.

6.1. Using Environment

We can access the active profiles from the Environment object by injecting it:

public class ProfileManager {
    @Autowired
    private Environment environment;

    public void getActiveProfiles() {
        for (String profileName : environment.getActiveProfiles()) {
            System.out.println("Currently active profile - " + profileName);
        }  
    }
}

6.2. Using spring.active.profile

Alternatively, we could access the profiles by injecting the property spring.profiles.active:

@Value("${spring.profiles.active}")
private String activeProfile;

Here, our activeProfile variable will contain the name of the profile that is currently active, and if there are several, it’ll contain their names separated by a comma.

However, we should consider what would happen if there is no active profile at all. With our code above, the absence of an active profile would prevent the application context from being created. This would result in an IllegalArgumentException owing to the missing placeholder for injecting into the variable.

In order to avoid this, we can define a default value:

@Value("${spring.profiles.active:}")
private String activeProfile;

Now, if no profiles are active, our activeProfile will just contain an empty string. And, if we want to access the list of them just like in the previous example, we can do it by splitting the activeProfile variable:

public class ProfileManager {
    @Value("${spring.profiles.active:}")
    private String activeProfiles;

    public String getActiveProfiles() {
        for (String profileName : activeProfiles.split(",")) {
            System.out.println("Currently active profile - " + profileName);
        }
    }
}

7. Example of Using Profiles

Now that the basics are out of the way, let’s take a look at a real example.

Consider a scenario where we have to maintain the datasource configuration for both the development and production environments. Let’s create a common interface DatasourceConfig that needs to be implemented by both data source implementations:

public interface DatasourceConfig {
    public void setup();
}

Following is the configuration for the development environment:

@Component
@Profile("dev")
public class DevDatasourceConfig implements DatasourceConfig {
    @Override
    public void setup() {
        System.out.println("Setting up datasource for DEV environment. ");
    }
}

And configuration for the production environment:

@Component
@Profile("production")
public class ProductionDatasourceConfig implements DatasourceConfig {
    @Override
    public void setup() {
       System.out.println("Setting up datasource for PRODUCTION environment. ");
    }
}

Now let’s create a test and inject our DatasourceConfig interface; depending on the active profile, Spring will inject DevDatasourceConfig or ProductionDatasourceConfig bean:

public class SpringProfilesWithMavenPropertiesIntegrationTest {
    @Autowired
    DatasourceConfig datasourceConfig;

    public void setupDatasource() {
        datasourceConfig.setup();
    }
}

When the “dev” profile is active spring injects DevDatasourceConfig object, and on call of setup() method following is the output:

Setting up datasource for DEV environment.

8. Profiles in Spring Boot

Spring Boot supports all the profile configuration outlined so far, with a few additional features.

The initialization parameter spring.profiles.active, introduced in section 4, can also be set up as a property in Spring Boot to define currently active profiles. This is a standard property that Spring Boot will pick up automatically:

spring.profiles.active=dev

To set profiles programmatically, we can also use the SpringApplication class:

SpringApplication.setAdditionalProfiles("dev");

To set profiles using Maven in Spring Boot, we can specify profile names under spring-boot-maven-plugin in pom.xml:

<plugins>
    <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
        <configuration>
            <profiles>
                <profile>dev</profile>
            </profiles>
        </configuration>
    </plugin>
    ...
</plugins>

And execute the Spring Boot specific Maven goal:

mvn spring-boot:run

But the most important profiles-related feature that Spring Boot brings is profile-specific properties files. These have to be named in the format applications-{profile}.properties.

Spring Boot will automatically load the properties in an application.properties file for all profiles, and the ones in profile-specific .properties files only for the specified profile.

For example, we can configure different data sources for dev and production profiles by using two files named application-dev.properties and application-production.properties:

In the application-production.properties file, we can set up a MySql data source:

spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/db
spring.datasource.username=root
spring.datasource.password=root

Then, we can configure the same properties for the dev profile in the application-dev.properties file, to use an in-memory H2 database:

spring.datasource.driver-class-name=org.h2.Driver
spring.datasource.url=jdbc:h2:mem:db;DB_CLOSE_DELAY=-1
spring.datasource.username=sa
spring.datasource.password=sa

In this way, we can easily provide different configurations for different environments.

9. Conclusion

In this quick tutorial, we discussed how to define a profile on a bean and how to then enable the right profiles in our application.

Finally, we validated our understanding of profiles with a simple but still real-world example.

The implementation of this Spring Security REST Tutorial can be found in the GitHub project – this is a Maven-based project, so it should be easy to import and run as it is.

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