set light properties through ros topic or service interface?

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Is it possible to set light properties through the ros topic or service interface on /gazebo? For example any of the properties set in the sdf file and available through menus in the gui I'd like to be able to adjust:

<light type="spot" name="base_light">
    <!--  Frames don't work in 5.0.1 XML Element[frame], child of element[light] not defined in SDF. Ignoring[frame]. You may have an incorrect SDF file, or an sdformat version that doesn't support this element. -->
    <!--frame name="base_link"-->
    <pose>0 0 0.1 1.57 0 0</pose>
    <diffuse>.9 .9 .9 1</diffuse>
    <specular>.1 .1 .1 1</specular>
    <attenuation>
        <range>20</range>
    </attenuation>
    <spot>
      <inner_angle>0.4</inner_angle>
      <outer_angle>1.0</outer_angle>
      <falloff>1.0</falloff>
    </spot>
    <direction>0 0 -1</direction>
    <cast_shadows>true</cast_shadows>
</light>

If not that, what about gz command line or gazebojs?

I'm using Ubuntu 14.04 with ROS Jade and Gazebo 5.0.1.