David Crossley wrote:
<snip/>
-- o -- The other purpose of my original message was to raise an alarm about the change in parameter names in the sitemap, which now do not correspond with code o.a.c.transformation.TraxTransformer
I'm more and more considering sitemap validation harmful.
why:
1) the sitemap logic is too hard to be validated from any validation language (it requires java runtime capabilitles)
2) it reduces the effort of clean and meaningful error messages in the treeprocessor
Example, try
<generate uri="..."/>
where the uri attribute is not allowed in generate (shoulc be 'src'), the treeprocessor totally ignores this and sends the empty string to the parser, resulting in the error
System ID not found!
Sitemap validation has stopped us from fixing the error messaging capabilities on mistakes.
I propose to blast the sitemap validation alltogether.
I don't follow you : a schema, although it cannot fully validate a sitemap, can easily check syntax inconsistencies like <map:generate uri="..."/>. The checks performed by the treeprocessor come at a lower lever such as controlling that a used component (type="...") exists, check variable expansion syntax, etc.
So it seems to me validation is good to easily write a syntax checker and let the java code in treeprocessor concentrate on more detailed "semantic" validation.
Now the problem, AFAIU, comes more from the fact that we're trying to validate not only the sitemap, but also the configuration of each component, which may take very various forms and obey to some complicated logic.
Something I've been thinking of long ago (but, as usual, never had the time to make real), is a "CheckableConfiguration" : a special implementation of the Configuration which would track usage of its data and could be queried after use for unused elements or attributes.
This would allow a very simple but complete validation :
- build the sitemap (the whole file is read in a Configuration object),
- lookup once each component in <map:components> to be sure they have been configured
- check your CheckableConfiguration for unused items.
Every unused item is a potential syntax error, and you can report them all at once.
Thoughts ?
Sylvain
-- Sylvain Wallez Anyware Technologies http://www.apache.org/~sylvain http://www.anyware-tech.com { XML, Java, Cocoon, OpenSource }*{ Training, Consulting, Projects }
