raise event from webservice to client

[nissiml]

hi.
I've build a web service and i want that all the clients of the service know
that a specific event occured at the server , my question is there a way to
do it ?

nissiml.

[Drew Marsh]

nissiml wrote:

I've build a web service and i want that all the clients of the
service know
that a specific event occured at the server , my question is there a
way to
do it ?

Well yes and no. First off there's a specification called WS-Eventing[1][2][3] that was developed to support this concept generically. It handles registering event handlers, updating subscriptions, etc. I suggest you read that as a jumping off point. Now, that said, there is no built-in support for this specification in the .NET Framework or WSE2.0. That's not to say that you couldn't implement the spec yourself very easily, in fact some people are trying to write a generic implementation based in WSE2.0... I believe that project is called PlumbworkOrange if you want to google it.

Now comes the final problem. This may not be an issue for your scenario, but it's important that it is understood. Events mean that the clients will need to be able to accept incoming TCP/IP requests. If you're using HTTP then this is done over port 80 (INBOUND). This is because events are fired as WSDL notification operations. The server is making a connection to the client and sending them a message (in effect, reversing the roles).

HTH,
Drew

[1] http://msdn.microsoft.com/webservice...s-eventing.asp
[2] http://blogs.msdn.com/bwill/archive/.../10/70964.aspx
[3] http://blogs.msdn.com/bwill/archive/.../12/72233.aspx