Maven: Profiles

Making your pom.xml do different things on localhost vs heroku, for example

Sometimes you want your pom.xml to do different things on localhost vs. when running on heroku.

Maven profiles, along with the Spring Boot *.properties files are one way to acheive this.

The code below, when added to a Maven pom.xml creates two different profiles called localhost and heroku:

Note that:

You can put a localhost.properties file in src/main/config/localhost that will override the shared properties in application.properties, and a heroku.properties in the src/main/config/heroku directory.
You can specify different dependencies, e.g. to use the H2 database on localhost, but postgres on heroku.
You can put a data.sql file in src/main/resources, but use these settings to control when it does and does not get loaded:
- In localhost.properties: spring.datasource.initialization-mode=always
- In heroku.properties: spring.datasource.initialization-mode=never

   <profiles>
        <profile>
            <id>localhost</id>
            <build>
                <resources>
                    <resource>
                        <directory>src/main/resources</directory>
                    </resource>
                    <resource>
                        <directory>src/main/config/localhost</directory>
                    </resource>
                </resources>
            </build>
            <dependencies>
                <dependency>
                    <groupId>com.h2database</groupId>
                    <artifactId>h2</artifactId>
                    <scope>runtime</scope>
                 </dependency>
            </dependencies>
        </profile>
        <profile>
            <id>heroku</id>
            <activation>
                <activeByDefault>true</activeByDefault>
            </activation>
            <build>
                <resources>
                    <resource>
                        <directory>src/main/resources</directory>
                    </resource>
                    <resource>
                        <directory>src/main/config/heroku</directory>
                    </resource>
                </resources>

            </build>
            <dependencies>
                <dependency>
                    <groupId>org.postgresql</groupId>
                    <artifactId>postgresql</artifactId>
                </dependency>

                <dependency>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-jdbc</artifactId>
                </dependency>
            </dependencies>
        </profile>
    </profiles>

How can I tell which profile(s) is/are active?

This command tells you which profile(s) are active:

mvn help:active-profiles

Maven: Profiles

How can I tell which profile(s) is/are active?

More on Profiles