Bogus error in save template from custom column

[rbroberts]

I have a Samsung Galaxy Note 10.1 (2014) that I'm trying to get files onto. I've defined a couple of custom columns pretty much out of the help pages on the calibre web site

series_stripped: {series:re(^(A|The|An)\s+,)||}
series_initials: {#stripped_series:re(([^\s])[^\s]+(\s|$),\1)}

But when I attempt to "Configure this device" for and use #series_initials in the template, I get an exception

{series:'ifempty($,field('author'))'||/}{#series_initials:|| }{title}
EXCEPTION: Value: unknown field #series_initials

I finally just saved it anyway. It worked.

Calibre 1.32, Fedora 20, x86-64

[chaley]

@kovid: the problem is that the MTP driver does not pass field metadata to the template editor dialog, so the editor has no idea what custom columns exist. I don't know if it can get the field metadata at that point in its life cycle.

[kovidgoyal]

You should certainly be able to get field metadata for the current library with get_gui().current_db.new_api.field_metadata

However, since the template setting is not per library, perhaps the proper fix is to no validate field names at all? I dont know if that's possible with validation_formatter however.

[chaley]

The problem isn't the validation formatter. It already indicates that any desired field exists.

The template editor uses the normal formatter so that it can show sample values for the template when editing composite column templates. Perhaps when it is in a no-book context it should use the validation formatter and not attempt show any sample values. That would be relatively easy to do.

[chaley]

Pushed a fix that grabs a copy of field metadata. Turned out not to be feasible to use the validation formatter because it doesn't parse general program mode templates.

This should be OK even in a non per-library context. If the user enters a custom column lookup key then it should be in the current library so that the template can be tested.