Registering Servlets and Filters

[Andreas Kollegger <ak...@tembopublic.org>]

With the current "Servlet Resolution" wiki page out-of-sync, does  
anyone have a bare-bones example of registering a servlet and/or  
filter with the Sling framework? It looks like a bundle just has to  
register a javax.servlet.Servlet service with the proper sling  
properties for it to get picked up. I've tried a simple OSGi  
Activator, but can't seem to get it to work.

Example BundleActivator.start...

     public void start( BundleContext bc )
         throws Exception
     {
         Dictionary props = new Properties();
	props.put("sling.servlet.paths", "/myservlet/html, /myservlet/txt");
         bc.registerService( javax.servlet.Servlet.class.getName(),  
new MyServlet(), props );
    }

Thanks for any guidance,
Andreas

Re: Registering Servlets and Filters

[Andreas Kollegger <ak...@tembopublic.org>]

Thanks to both Felix and Bertrand, servlets and filters are both now  
working.

Now, I'm moving on to deploying sitemesh as a filter. An initial  
challenge is that SiteMesh attempts to load configuration files using  
the ServletContext, which doesn't seem to search the bundle that  
loaded the filter. Is there a way to register search paths for the  
shared ServletContext? Otherwise I'll look into hacking SiteMesh to  
use alternative configuration methods.

Thanks,
Andreas


On May 7, 2009, at 3:02 AM, Felix Meschberger wrote:

> Hi,
>
> Andreas Kollegger schrieb:
>> With the current "Servlet Resolution" wiki page out-of-sync, does  
>> anyone
>> have a bare-bones example of registering a servlet and/or filter with
>> the Sling framework? It looks like a bundle just has to register a
>> javax.servlet.Servlet service with the proper sling properties for  
>> it to
>> get picked up. I've tried a simple OSGi Activator, but can't seem  
>> to get
>> it to work.
>>
>> Example BundleActivator.start...
>>
>>    public void start( BundleContext bc )
>>        throws Exception
>>    {
>>        Dictionary props = new Properties();
>>    props.put("sling.servlet.paths", "/myservlet/html, /myservlet/ 
>> txt");
>>        bc.registerService( javax.servlet.Servlet.class.getName(), new
>> MyServlet(), props );
>>   }
>
> This is almost correct. The property value is either a single string  
> or
> an array of strings. So your example should really be:
>
>    props.put("sling.servlet.paths",
>           new String[]{ "/myservlet/html", "/myservlet/txt" });
>
> But since you registered with absolute paths, the resource types must
> also be absolute. Thus your example (with the fix for the property
> value) should work for .html and .txt requests to resources whose
> resource type "/myservlet".
>
> If your resource types are relative -- e.g. "myservlet" -- you should
> register with relative paths as in :
>
>    props.put("sling.servlet.paths",
>           new String[]{ "myservlet/html", "myservlet/txt" });
>
> or better yet to register with two properties, one for the resource  
> type
> and for the extensions supported:
>
>    props.put("sling.servlet.resourceTypes", "myservlet");
>    props.put("sling.servlet.extensions", new String[]{"html","txt"});
>
>
> HTH
>
> Regards
> Felix
>
>>
>> Thanks for any guidance,
>> Andreas
>>
>>

Re: Registering Servlets and Filters

[Felix Meschberger <fm...@gmail.com>]

Hi,

Andreas Kollegger schrieb:
> With the current "Servlet Resolution" wiki page out-of-sync, does anyone
> have a bare-bones example of registering a servlet and/or filter with
> the Sling framework? It looks like a bundle just has to register a
> javax.servlet.Servlet service with the proper sling properties for it to
> get picked up. I've tried a simple OSGi Activator, but can't seem to get
> it to work.
> 
> Example BundleActivator.start...
> 
>     public void start( BundleContext bc )
>         throws Exception
>     {
>         Dictionary props = new Properties();
>     props.put("sling.servlet.paths", "/myservlet/html, /myservlet/txt");
>         bc.registerService( javax.servlet.Servlet.class.getName(), new
> MyServlet(), props );
>    }

This is almost correct. The property value is either a single string or
an array of strings. So your example should really be:

    props.put("sling.servlet.paths",
           new String[]{ "/myservlet/html", "/myservlet/txt" });

But since you registered with absolute paths, the resource types must
also be absolute. Thus your example (with the fix for the property
value) should work for .html and .txt requests to resources whose
resource type "/myservlet".

If your resource types are relative -- e.g. "myservlet" -- you should
register with relative paths as in :

    props.put("sling.servlet.paths",
           new String[]{ "myservlet/html", "myservlet/txt" });

or better yet to register with two properties, one for the resource type
and for the extensions supported:

    props.put("sling.servlet.resourceTypes", "myservlet");
    props.put("sling.servlet.extensions", new String[]{"html","txt"});


HTH

Regards
Felix

> 
> Thanks for any guidance,
> Andreas
> 
> 

Re: Registering Servlets and Filters

[Bertrand Delacretaz <bd...@apache.org>]

Hi,

On Wed, May 6, 2009 at 11:12 PM, Andreas Kollegger
<ak...@tembopublic.org> wrote:
> With the current "Servlet Resolution" wiki page out-of-sync, does anyone
> have a bare-bones example of registering a servlet and/or filter with the
> Sling framework?...

The http://svn.apache.org/repos/asf/incubator/sling/trunk/launchpad/test-services/
example bundle contains a few servlets using different registration
mechanisms.

For filters, there's an example at [1].

-Bertrand

[1]  https://svn.eu.apache.org/repos/asf/incubator/sling/trunk/samples/simple-demo/src/main/java/org/apache/sling/sample/filter/ZipFilter.java