[seam-dev] Replacing pages.xml
I have been thinking about the replacement for pages.xml. Even though JSF2 has made some
aspects of pages.xml redundant, pages.xml is still important as it allows you to apply
actions/security setting etc to a large number of pages at once using wildcards. With that
said however it would be nice to move to a design that is more typesafe and extensible. I
have come up with a preliminary idea of how this might work, I will explain with an
example:
@PageMetadata
public @Interface SecurityConfig
{
boolean loginRequired();
String restrict();
}
/**
* This bean will only be considered for injection when the context path is
* /app/restricted/*, and it is the most specific page available.
*/
@ViewId("/app/restricted/*")
@SecurityConfig(loginRequired=true)
public class RestrictedArea extends Page
{
}
This may also be configured via XML using seam-xml.
There is nothing special about the page class, it is an empty class
that is provided solely to be configured with annotations:
<Page>
<ViewId>/app/restricted/*</ViewId>
<SecurityConfig loginRequired="true" />
</Page>
The application can get access to this information in a number of ways:
@Inject PageDataProvider<SecurityConfig> data;
public void doStuff()
{
//get the most specific result
SecurityConfig security = data.get();
//get all applicable results
List<SecurityConfig> secinfo = data.getAll();
//secinfo is ordered from most to least specific,
//secinfo.get(0) will be equal to data.get()
}
Alternatively the most specific result can be injected directly:
@Inject SecurityConfig data;
We could also support an event based approach:
public void pageEvent(@Observes @Rendered("/secure/*") Page page, SecurityConfig
config)
{
//do stuff
}
Does this sound like a good approach? I am fairly sure all this can be implemented as a
portable extension.