Problem statement

I am trying to get the output of a validation written into a log file.

The documentation of validate states:

Application Options:
-q, --quiet silence logs
--output=LOG-FILE redirect logs to file

But this does not seem to be a valid flag anymore:

$ swagger --output=logfile validate swagger.json
unknown flag `output'

The flag name seem to have changed to --log-output

So I've tried to use this option, and while a file with the right name is created, it is always empty, and the output is still printed out on the console.

$ swagger --log-output=logfile validate swagger.json

The swagger spec at "swagger.json" is invalid against swagger specification 2.0.
See errors below:
- some references could not be resolved in spec. First found: object has no key "UserSecret"
- could not resolve reference in "/secrets".POST to $ref : object has no key "UserSecret"

$ cat logfile
$ 

How can I get the output written to a file?

Environment

swagger version: 0.27.0
go version: 1.15.15
OS: Ubuntu 20.04