Netkan option to validate .ckan file

[HebaruSan]

Motivation

KSP-CKAN/xKAN-meta_testing#51 (comment)

Also, in theory NetKAN can consume a CKAN and output a validated CKAN. Maybe md5 before/after and we can catch when a CKAN is handcrafted (which we never want to do).

This would help to unify our pull request validation logic, as the CKAN-meta script could use netkan.exe for validation just as the NetKAN script does.

Changes

Now a new command format is supported:

mono netkan.exe --validate-ckan Astrogator/Astrogator-v0.9.2.ckan

This will load the indicated .ckan file and run Netkan's standard validators on it (see #2788). If there are any problems, the usual error will be printed and the process will exit with a failure code.

If the .ckan file is valid, it will be printed with standard pretty formatting and property sorting, as if it had just been generated by netkan.exe, and the process will exit with a success code.

[techman83]

This is awesome! We have the hashing functions already, maybe an --output-sha256 that we can compare (or maybe it can do it internally?). Not needed to merge this.

[DasSkelett]

If the .ckan file is valid, it will be printed with standard pretty formatting and property sorting, as if it had just been generated by netkan.exe, and the process will exit with a success code.

Could we have an option to overwrite the .ckan if it is valid, to replace it with the pretty formatting? E.g. a [-o] flag.

[techman83]

Technically that's NetKANs job 😉 I think maybe I didn't think through the option and got caught up in the excitement 😅

Although there is hope, as part of the validate command checksum the input and output to see if they match, potentially giving a different exit code for each exception type.