loop_range_step.xml

<workflow-app name="loop_${loop_name}_(${loop_value}_of_${loop_start}_to_${loop_end})"
              xmlns="uri:oozie:workflow:0.4">
    <start to="check_fork"/>
    
    <decision name="check_fork">
        <switch>
            <case to="fork">${loop_parallel eq "true"}</case>
            <case to="run_serial">${loop_parallel eq "false"}</case>
            <default to="error"/>
        </switch>
    </decision>
    
    <!-- _______________________________________________________________________________ -->
    
    <!-- We implement parallelism through a recursively-built tree of two-pronged forks
         where the left prong is the action we want to loop over and the right prong is the
         next fork down the tree. -->
         
    <fork name="fork">
        <path start="check_run_parallel"/>
        <path start="check_continue_parallel"/>
    </fork>
    
        <decision name="check_run_parallel">
            <switch>
                <!-- We add zero to gently persuade the strings to be ints -->
                <case to="run_parallel">${(loop_value + 0) le (loop_end + 0)}</case>
                <default to="join"/>
            </switch>
        </decision>
    
        <action name="run_parallel">
            <sub-workflow>
                <app-path>${loop_action}</app-path>
                <propagate-configuration/>
            </sub-workflow>
            <ok to="join"/>
            <error to="error"/>
        </action>
    
        <decision name="check_continue_parallel">
            <switch>
                <case to="continue_parallel">${(loop_value + 0) lt (loop_end + 0)}</case>
                <default to="join"/>
            </switch>
        </decision>
    
        <action name="continue_parallel">
            <sub-workflow>
                <!-- Take the red pill -->
                <app-path>${wf:appPath()}</app-path>
                <propagate-configuration/>
                <configuration>
                    <property>
                        <name>loop_value</name>
                        <value>${loop_value + 1}</value>
                    </property>
                </configuration>
            </sub-workflow>
            <ok to="join"/>
            <error to="error"/>
        </action>
        
    <join name="join" to="end"/>
    
    <!-- _______________________________________________________________________________ -->
    
    <!-- We implement serial looping (as like a traditional for loop) by recursively
         running the action until we reach the end of the range. -->
    
    <decision name="check_run_serial">
        <switch>
            <case to="run_serial">${(loop_value + 0) le (loop_end + 0)}</case>
            <default to="end"/>
        </switch>
    </decision>

    <action name="run_serial">
        <sub-workflow>
            <app-path>${loop_action}</app-path>
            <propagate-configuration/>
        </sub-workflow>
        <ok to="check_continue_serial"/>
        <error to="error"/>
    </action>

    <decision name="check_continue_serial">
        <switch>
            <case to="continue_serial">${(loop_value + 0) lt (loop_end + 0)}</case>
            <default to="end"/>
        </switch>
    </decision>

    <action name="continue_serial">
        <sub-workflow>
            <app-path>${wf:appPath()}</app-path>
            <propagate-configuration/>
            <configuration>
                <property>
                    <name>loop_value</name>
                    <value>${loop_value + 1}</value>
                </property>
            </configuration>
        </sub-workflow>
        <ok to="end"/>
        <error to="error"/>
    </action>
    
    <!-- _______________________________________________________________________________ -->

    <kill name="error">
        <message>Oops!</message>
    </kill>
                                        
    <end name="end"/>
</workflow-app>