Nested Layer Group metadata

[tomkralidis]

Currently (4.2.0), one can have an extra nesting of <Layer> elements, i.e.:

<Layer>
    <Name>mum2_ogc_workshop</Name>
    <Title>Sample WMS for MUM2 OGC Web Services Workshop</Title>
    <SRS>EPSG:4326</SRS>
    <LatLonBoundingBox minx="-180" miny="-90" maxx="180" maxy="90" />
    <Layer>
      <Name>Imagery</Name>
      <Title>Imagery</Title>
      <Layer queryable="0" opaque="1" cascaded="0">
        <Name>land_shallow_topo_2048</Name>
        <Title>Land Surface, Shallow Water, and Shaded Topography</Title>
        <Abstract>abstract info goes here</Abstract>

..which is triggered by GROUP and "wms_group_title" (the group in this case is
"Imagery").

Can we add a stub so that an abstract is also available for GROUP elements, in
addition to Name and Title, i.e.:


<Layer>
    <Name>mum2_ogc_workshop</Name>
    <Title>Sample WMS for MUM2 OGC Web Services Workshop</Title>
    <SRS>EPSG:4326</SRS>
    <LatLonBoundingBox minx="-180" miny="-90" maxx="180" maxy="90" />
    <Layer>
      <Name>Imagery</Name>
      <Title>Imagery</Title>
      <Abstract>This is a bunch of imagery layers</Abstract>
      <Layer queryable="0" opaque="1" cascaded="0">
        <Name>land_shallow_topo_2048</Name>
        <Title>Land Surface, Shallow Water, and Shaded Topography</Title>
        <Abstract>abstract info goes here</Abstract>

[assefa]

Added wms_group_abstract (works like wms_group_title).
Reassign to jeff for doc update.

[tomkralidis]

When I tested this, I tried multiple different wms_group_abstract values for
layers under the same "wms_group_title".  What happens is that the last
wms_group_abstract gets outputted.

Is this okay?  Maybe wms_group_abstract should be defined within each
LAYER/METADATA?  I wonder whether wms_group_<groupname>_abstract would be better
used, at something like the WEB/METADATA level?

[dmorissette]

> When I tested this, I tried multiple different wms_group_abstract values for
> layers under the same "wms_group_title".  What happens is that the last
> wms_group_abstract gets outputted.

Are you sure you got the lat one? You should be getting only the first one,
that's the way wms_group_title has always worked, and wms_group_abstract uses th
sae function now. If you get a different behavior then there may be a bug.

BTW, the wms_group_title doc could use a clarification:

"Description: (Optional) A human-readable name for the group that this layer
 belongs to. Only one layer for the group needs to contain  wms_group_title,
 MapServer will find and use the value."

When you update docs for this, please add a clarification for wms_group_title
and wms_group_abstract that the value found for the first layer in the group is
used. So if multiple layers have wms_group_* set then only the first value is used.

[assefa]

I did a quick tests and I get the abstract of the first layer. Is this still an
issue for you Tom or the only missing thing the docs ?

[tomkralidis]

This is okay.  Only the docs now.

[dmorissette]

Reopening because doc is not done yet (assigned to Jeff).

[jmckenna@…]

added wms_group_abstract to wms-server doc and modified wording as suggested. 
committed to cvs.