I use maven-jgit-buildnumber-plugin(github) In one case I define it in profile:
<profile>
<id>make-buildnumber</id>
<activation>
<activeByDefault>true</activeByDefault>
</activation>
<build>
<plugins>
<plugin>
<groupId>ru.concerteza.buildnumber</groupId>
<artifactId>maven-jgit-buildnumber-plugin</artifactId>
<executions>
<execution>
<id>make-buildnumber</id>
<goals>
<goal>extract-buildnumber</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</profile>
In other case I point it in build section of the pom.xml.
In pluginManagement section I try to use variables from plugin:
<plugin>
<artifactId>maven-jar-plugin</artifactId>
<version>2.6</version>
<configuration>
<archive>
<manifestSections>
<manifestSection>
<name>SCM</name>
<manifestEntries>
<Branch>${git.branch}</Branch>
</manifestEntries>
</manifestSection>
</manifestSections>
</archive>
</configuration>
</plugin>
In first case it is not working, variable is null. Why???