loop.xml

<workflow-app name="loop_${loop_name}" xmlns="uri:oozie:workflow:0.4">
    <start to="check_type"/>

    <decision name="check_type">
        <switch>
            <case to="loop_range">${loop_type eq "range"}</case>
            <case to="loop_list">${loop_type eq "list"}</case>
            <default to="error"/>
        </switch>
    </decision>
    
    <action name="loop_range">
        <sub-workflow>
            <app-path>/your/path/to/loop_range_step.xml</app-path>
            <propagate-configuration/>
            <configuration>
                <property>
                    <name>loop_value</name>
                    <value>${loop_start}</value>
                </property>
            </configuration>
        </sub-workflow>
        <ok to="end"/>
        <error to="error"/>
    </action>

    <action name="loop_list">
        <sub-workflow>
            <app-path>/your/path/to/loop_list_step.xml</app-path>
            <propagate-configuration/>
            <configuration>
                <!-- See loop_list_step.xml for what's going on here -->
                <property>
                    <name>loop_value</name>
                    <value>${replaceAll(replaceAll(loop_list, "([^,]*),?(.*)", "$1"),
                                        "^$", "--NOVALUE--")}</value>
                </property>
                <property>
                    <name>loop_list</name>
                    <value>${replaceAll(replaceAll(loop_list,"([^,]*),?(.*)", "$2"),
                                        "^$", "--ENDOFLIST--")}</value>
                </property>
            </configuration>
        </sub-workflow>
        <ok to="end"/>
        <error to="error"/>
    </action>       
                                        
    <kill name="error">
        <message>Oops!</message>
    </kill>

    <end name="end"/>
</workflow-app>