Jeremias Maerki wrote: <snip/>
Conclusion: Using the master-name approach instead of including printer-specific commands adds flexibility for media and paper tray selection. The only thing that will be useful is a parameter to FOP and/or an extension value in XSL-FO which specifies the actualy printer that the print job is to be generated for so the renderer can use the right set of mapping rules.
I'm sorry Jeremias, your arguments here have failed to convince me that your suggested approach is the best way. I'm still in favour of using extension elements for PS, PCL and AFP. It should be possible to add the extension elements into the Intermediate Format XML, as the printer to be used may not be known until later in the processing (as you already suggested and that bit I agree with)
If the master name to media name mapping is placed in the configuration file then there is no means to override it for a single document. After all there is only 1 configuration file, and it cannot be changed at runtime. Allowing extension elements in the IF XML is the most flexible way. Then you don't need to know the printer when working in XSLT and FO, but when the IF XML is processed the destination printer should be known. (It is in our system anyway :)
As you've already mentioned in PS there is more than one way of specifying tray selection. So assuming one particular way (/MediaType) would be rather limiting in my opinion and not desirable. Perhaps you didn't mean that, but that is my understanding of what you said.
I also think this is a little bit Out of Scope for FOP. FOP should provide some means to achieve tray selection via the Extension element mechanism, but providing master name to media name mapping in the configuration along with making assumptions about the Postscript and PCL to be inserted into the output is going a step too far I think.