I am using
syslog-ng's mongodb plugin and it works great, but I can't find a way to customize the format of the saved log entries ("DATE", "FACILITY",...). Does anyone know how to do this?
If you mean that you would like to rename the fields (which I think is what you are asking), then you can try something like this:
You are going to have to do it for each one though, I can't think of any way to do it auto-magically.
For the record, if you don't set a scope, then you don't need to exclude the DATE field, because it wouldn't be included anyway.
With syslog-ng 3.4, there is another way to customize key names, which may or may not be useful. I wrote a small howto demonstrating and briefly explaining what one can do with value-pairs.