[Spread-users] extending spread

[jabe at gfz-potsdam.de]

I am looking for a way to filter messages sent over spread. My favourite 
solution would be to extend spread with a "plugin" to do the filtering on the 
server side. By now we are setting up a server on top of spread that does all 
the filtering, manages client connections and so on. This method is far from 
optimal and wastes a lot of network bandwidth, because messages are being 
sent twice (client -> spread -> server on top of spread -> spread -> client) 
as much as necessary.

The reason: Some messages has to be stored inside a database BEFORE they are 
passed to the subscribed clients so that the clients can rely on the 
persistence of these messages.

Furthermore we want to restrict groups. The available groups are defined by 
the 'server on top of spread'. Clients can subscribe only these groups and 
they are neither priviledged to send to an unknown nor to create a new group. 

Is there some kind of "extension" API in spread to meet these requirements?

Regards,
Jan