Setting expiry date for a layer

[Stephen Woodbridge]

One simple way to achieve this would be to write a simple wrapper in a 
script that would emit the appropriate headers before spooling the image 
to the browser.

-Steve W

Ludwig Max Brinckmann wrote:
> I have a map layer reading from a PostGIS database that is being 
> populated asynchronously through a separate process in the background.
> 
> My mapclient displays this data through a WMS request and merges it on 
> the fly (openlayers-like) with WMS layers coming from other sources. 
> While most of the layers are static ( i.e. do not change over time), my 
> PostGIS layer is highly dynamic and displaying up-to-date information is 
> crucial to the application.
> 
> Currently, whenever refreshing the map image, the browser will simply 
> fetch the image again from the cache, meaning that the viewer displays 
> old data.
> 
> Is there a way in mapserver to set the expiration time of the image 
> supplied, so that my mapping client would automatically refresh, rather 
> than reload the old image from the browser cache? (it is good enough for 
> the application to refresh every time, rather than only when Postgis has 
> changed, so simply setting the expiry time in the http header would be 
> great)
> 
> Ludwig
> 
>