Why does exec-maven-plugin run all phases twice?

Question

When I run a build with maven using the exec-maven-plugin, it runs everything twice for some reason. Is there a way to fix this so it only runs once? I've tried setting my phase in the pom.xml to compile and package and either way, it runs twice. My pom looks like

<build>
  <plugins>
    <plugin>
      <artifactId>exec-maven-plugin</artifactId>
      <groupId>org.codehaus.mojo</groupId>
      <version>1.0</version>
      <executions>
        <execution>
          <id>foo</id>
          <phase>compile</phase>
          <goals>
            <goal>exec</goal>
          </goals>
        </execution>
      </executions>
      <configuration>
        <executable>bash</executable>
        <commandlineArgs>myscript.sh</commandlineArgs>
      </configuration>
     </plugin>
    </plugins>
  </build>

Answer 1

It turned out that adding the phase tag caused the command to get executed twice. Leaving that out, it is now getting run once as expected. I guess it doesn't matter what phase I give it now, it'll always run the goal, which works for me.

Answer 2

If you need to run this early in the build, excluding the phase isn't an option.

You can do something like this instead in the plugin config:

<executions>
    <execution>
        <id>default</id>
        <phase>none</phase> <!-- disable the default execution in validate phase -->
    </execution>
    <execution>
        <id>exec-do-something</id>
        <goals>
            <goal>java</goal>
        </goals>
        <phase>generate-sources</phase><!-- now it will run once but in an earlier phase -->
    </execution>
</executions>