cocoon-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Sylvain Wallez <>
Subject Re: Listener in cocoon 2.2
Date Wed, 30 Sep 2009 10:12:04 GMT
Dominic Mitchell wrote:
> On Tue, Sep 29, 2009 at 10:38 AM, Thorsten Scherler 
> < 
> <>> wrote:
>     Hi all,
>     what is the best way to implement a Listener in cocoon 2.2?
>     I our use case we have a "listener" uri that got dispatched by an
>     external application to notify that some resources have changed and
>     invalid our cache for that resource.
>     The thing is that the uri do not have to/will not return anything
>     in the
>     body only in the request header.
>     The current solution which was presented to us uses a custom generator
>     which will not output anything. That just does not feel right.
>     I did a small test with
>     <map:match pattern="notify">
>      <map:act type="notify"/>
>      <map:generate src="notify.xml"/>
>      <map:serialize/>
>     </map:match>
>     but that is just to make it work the normal cocoon way. The notify.xml
>     is a dummy and I am not really thrilled about that neither.
>     Using flow seems to be as well too much since we just want a simple
>     listener that returns only http header.
> Last time I needed something like this I used the "empty:" source. 
>  Combined with a reader, that should do the track.
>   <map:match pattern="notify">
>     <map:read src="empty:" />
>   </map:match>
> This is untested — I can't remember if there are any quirks.

Good trick. Now more than a source, which involves the SourceResolver 
machinery, a very simple stupid Reader can also do the trick. Or does 
the "empty" source already exist?

<map:match pattern="notify">
  <map:act type="notify">
    <map:read type="empty" status-code="200"/>


Sylvain Wallez -

View raw message