Hi Thomas,<div>I followed mod-geocache since the initial announcemente and I'm really impressed.</div><div>I'll reread the rfc it tomorrow and let you have my thoughts by the evening.</div><div><br></div><div>Best regards,</div>
<div>Umberto</div><div><br><div class="gmail_quote">On Tue, May 24, 2011 at 10:21 AM, thomas bonfort <span dir="ltr"><<a href="mailto:thomas.bonfort@gmail.com">thomas.bonfort@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
no comments?<br>
<br>
I would think that the proxying nature of mod-geocache integration<br>
needs discussion. The scenario is as follows:<br>
<br>
* user creates a mapfile that needs tilecaching support, placed at<br>
/path/to/mapfile.map. This mapfile contains some configuration<br>
keywords to declare what layers are to be cached, the definitions of<br>
the tile grids that will be used, where to store cached tiles, etc...<br>
<br>
* apache configuration is set like:<br>
<Location /mymapservice><br>
SetHandler geocache<br>
GeocacheConfigFile /path/to/mapfile<br>
</Location><br>
<br>
* user publishes the url to his service as <a href="http://myhost/mymapservice" target="_blank">http://myhost/mymapservice</a><br>
* incoming requests to /mymapservice are treated as follows:<br>
* WMS requests that correspond to tile requests of a cached layer<br>
are intercepted by mod-geocache<br>
* WMS requests that correspond to general getMap requests of a<br>
cached layer are treated by mod-geocache and are reconstructed by<br>
assembling cached tiles (or forwarded to mapserver if configured so)<br>
* non wms tiled requests are treated by mod-geocache, on the urls<br>
<a href="http://myhost/mymapservice/(wmts|tms|kml|etc...)/" target="_blank">http://myhost/mymapservice/(wmts|tms|kml|etc...)/</a><br>
* all other requests (WMS on a grid with different SRID, WFS, WCS,<br>
etc...) are forwarded to <a href="http://localhost/cgi-bin/mapserv" target="_blank">http://localhost/cgi-bin/mapserv</a> (or another<br>
server+path)?map=/path/to/mapfile&(forwarded incoming request params).<br>
With some configuration, the user can also configure specific requests<br>
to be forwarded to a specific url, eg WFS-T requests go to<br>
<a href="http://localhost/cgi-bin/tinyows" target="_blank">http://localhost/cgi-bin/tinyows</a>.<br>
<br>
This scenario has the advantage that the mod-geocache configuration<br>
and operation is quite decoupled from the mapserver one, and allows<br>
the publication of a single entry point into *all* the services<br>
offered by /path/to/mapfile.map. It has two inconveniences:<br>
* all non tiled requests are proxied, and therefore go through a<br>
second http request. This adds the overhead of mod-geocache parsing<br>
(which is minimal as it consists of checking the service is WMS, then<br>
that the requested layers are cached, that the SRS corresponds to the<br>
layer's tile grid, and optionally finally that the extent+size matches<br>
the configured tile grids), plus the overhead of a second http request<br>
(which should be minimal as it happens on localhost or the local<br>
network).<br>
* WMS GetCapabilities responses are generated by mapserver, and<br>
therefore would not contain the WMS-C extension indicating that<br>
there's a cache available. We could imagine that mod-geocache<br>
intercepts the mapserver-generated xml, and inserts the WMS-C vendor<br>
extension required to publicize the tiled service.<br>
<br>
--<br>
<font color="#888888">thomas<br>
</font><div><div></div><div class="h5"><br>
On Fri, May 20, 2011 at 17:22, thomas bonfort <<a href="mailto:thomas.bonfort@gmail.com">thomas.bonfort@gmail.com</a>> wrote:<br>
> I've committed a draft version of rfc 71 here:<br>
> <a href="http://trac.osgeo.org/mapserver/browser/trunk/docs/en/development/rfc/ms-rfc-71.txt" target="_blank">http://trac.osgeo.org/mapserver/browser/trunk/docs/en/development/rfc/ms-rfc-71.txt</a><br>
><br>
> awaiting your comments...<br>
><br>
> --<br>
> thomas<br>
><br>
_______________________________________________<br>
mapserver-dev mailing list<br>
<a href="mailto:mapserver-dev@lists.osgeo.org">mapserver-dev@lists.osgeo.org</a><br>
<a href="http://lists.osgeo.org/mailman/listinfo/mapserver-dev" target="_blank">http://lists.osgeo.org/mailman/listinfo/mapserver-dev</a><br>
</div></div></blockquote></div><br></div>