UDL is primarily for keyword-based languages. Logfiles are much more “positional”-based (or, at least, pattern-based).
The plugin CSVLint adds a lexer plugin (so it behaves more like a builtin lexer than a UDL). I think it might be able to specify alternate characters instead of comma , for the separator (but I don’t have the plugin installed right now, so cannot check for you).
Alternately, there’s the AnalysePlugin, which allows you to set up multiple regex to highlight various patterns; it’s primary use is to apply multiple highlights to log files, so it’s probably pretty close to what you want.
I would like to have json language style applied to properties section too
Yeah, UDL cannot inherit from a builtin lexer, so wouldn’t be able to do that. And the CSVLint probably couldn’t even approximate that. OTOH, the AnalysePlugin, with its regex, would probably be able to get something reasonable.