Prior to this change, `pretty-printer` was a special type of Printer
that wrote output to `Stdout`, unless explicitly asked to write to a
given file. Kubescape used `pretty-printer` as an output format by
default. This behavior created the following inconsistencies:
- When invoked as `kubescape scan`, Kubescape would use `pretty-printer`
by default, and it would output the scan resluts in the
`pretty-printer` format to `Stdout`.
- When invoked as `kubescape scan --format=pretty-printer`, the behavior
would be as above.
- When invoked as `kubescape scan --format=FORMAT`, where `FORMAT` is any
format except for `pretty-printer`, Kubescape would write the results
to a sensible default file for the selected format. This is in
contrast to how `--format=pretty-printer` would still output to
`os.Stdout`, and not an output file.
- When invoked as `kubescape scan --format=ANY_FORMAT --output=FILENAME`, where
`ANY_FORMAT` is any format, including `pretty-printer`, Kubescape
would write the results to the provided `FILENAME` in the given
`ANY_FORMAT`, and not write any results to `Stdout`.
The aforementioned situation complicates life for users running
Kubescape in CI, where Kubescape would skip writing the results to
`Stdout` and only write to the provided output file.
Moreover, with the addition of support for multiple output formats and,
hence, files, this introduces the following ambiguity:
- When invoked as `kubescape scan --format=json,pdf,pretty-printer
--output=FILENAME`, should Kubescape treat `pretty-printer` as a
format for the output file, or just an instruction to also print the
results to `Stdout`?
To fix these inconsistencies and ambiguities, this commit introduces the
following changes:
- Kubescape will always print results to `Stdout` using the
PrettyPrinter format.
- The `--format` CLI flag will control the format(s) in which the results
will be written to one or many *output* files. This breaks the
previous behavior that running `kubescape scan
--format=pretty-printer` would not produce an output file, and only
write to `Stdout`. After this change, the same invocation will still
write to `Stdout`, but also produce a `report.txt` file in the
PrettyPrinter format.
Vlad Klokun
Amir Malka
David Wertenteil