[Tilecache] Basic Questions

[Jeffrey Johnson]

Got the seed() function to work! Thanks for adding this. One quick
question. If the tiles for the Layer passed already exist, does this
function recognize this and not build them again? Or does it just go
ahead and build them again regardless.

Thanks,

Jeff

On 9/24/07, Christopher Schmidt <crschmidt at metacarta.com> wrote:
> On Mon, Sep 24, 2007 at 11:57:29AM -0700, Jeffrey Johnson wrote:
> > Ok, some more questions.
> >
> > I am calling tilecache like this in JS
> >
> >       map = new OpenLayers.Map( $('map'));
> >       currentLayer = new OpenLayers.Layer.WMS(layer_name,
> > ["http://localhost/cgi-bin/tilecache-1.9/crystalnavigator.py?srcFile="
> > + srcFile + "&layer_name=" + layer_name,
> > "http://localhost/cgi-bin/tilecache-1.9/crystalnavigator.py?srcFile="
> > + srcFile + "&layer_name=" + layer_name], {'layers':layer_name},
> > {maxResolution:4, numZoomLevels:3, maxExtent: new
> > OpenLayers.Bounds(0,0,1024,1024)});
> >       map.addLayer(currentLayer);
> >       map.zoomToMaxExtent();
> >
> > and crystalnavigator.py looks like this
> >
> > #!C:/Python25/python.exe -u
> >
> > import cgi
> > from TileCache.Service import Service, modPythonHandler, cgiHandler
> > from TileCache.Layer import Layer, ImageLayer
> > from TileCache.Cache import DiskCache
> >
> > layerList = {}
> >
> > form = cgi.FieldStorage()
> > srcFile = form["srcFile"].value
> > layer_name = form["layer_name"].value
> > layerList[layer_name] = ImageLayer(layer_name, file=srcFile,
> > filebounds="0,0,1024,1024", bbox="0,0,1024,1024",
> > maxresolution="4",levels="3", extension="jpeg")
> >
> > myService = Service (DiskCache("c:/tmp/crystalimagecache"), layerList)
> >
> > def handler (req):
> >     return modPythonHandler(req, myService)
> >
> > if __name__ == '__main__':
> >     cgiHandler(myService)
> >
> > So, my question is. Is there someway that I can seed the cache or
> > precache images when I am not using a cfg file like this.
>
> Not trivially. However, there is a seed() function, which (as of latest
> trunk about 3 hours ago) you can pass a Service and Layer to, and
> pre-cache. If you read the code, you may be able to get it.
>
> > Likewise, is there someway to blow away the cache intelligently ...
> > without just blowing away the entire directory structure.
>
> Not for big caches. tilecache_clean does a last-modified based LRU
> cleaning, but it's slow enough to be prohibitive with more than a gig or
> two of tiles.
>
> Regards,
> --
> Christopher Schmidt
> MetaCarta
>