<plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-antrun-plugin</artifactId>
        <version>3.0.0</version>
        <executions>
          <execution>
            <id>attach-artifact</id>
            <phase>package</phase>
            <goals>
              <goal>run</goal>
            </goals>
            <configuration>
              <target>
                <zip destfile="my-project-src.zip"
                     basedir="."
                     includes="*.*"
                  />
                <attachartifact file="my-project-src.zip" classifier="src" type="zip"/>
              </target>
            </configuration>
          </execution>
        </executions>
      </plugin>