[OpenLayers-Users] Auto-refreshing a GeoRSS layer

[christopher.schmidt at nokia.com]

On Aug 10, 2010, at 1:05 PM, ext Hubick, William wrote:

> Hi Everyone,
>  
> My project is considering GeoRSS as our data-sharing standard with partners. I am pleased with how easily OpenLayers will display GeoRSS points, but I'm wondering how other developers ensure efficient auto-updates. My first impression was that OpenLayers would automatically check a GeoRSS XML file and automatically load updates (i.e., like an RSS aggregator). When further exploring, it seems like custom code must be written to auto-update the layer.
>  
> Am I missing something? Is there a way to ensure new points added to a GeoRSS file are automatically, efficiently loaded by OpenLayers (without page refresh)? It seems like there must be a better way to update the layer than destroying and reloading the GeoRSS layer.

In general, RSS feeds are not updated in 'realtime' -- there
is no way that an RSS feed can 'push' data to the client consuming
it.

Using an OpenLayers.Layer.Vector, with a Protocol.HTTP, and a 
Strategy.Refresh, which has:

     * Property: interval
     * {Number} Auto-refresh. Default is 0.  If > 0, layer will be refreshed 
     *     every N milliseconds.
     */
    interval: 0,

would allow you to tell OpenLayers to re-load the GeoRSS file
from the server every $interval milliseconds.

This doesn't solve the need to have real-time updates, but it allows
you to implement a refresh without a page reload.

-- Chris

> Any help would be greatly appreciated!
>  
> Thanks in advance,
>  
> Bill
>  
> Bill Hubick
> Cobham Analytic Solutions
> william.hubick at cobham.com
>  
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