tool/update_tool: new tool to explore db updates

[lavocatt]

Db updates are tricky to review. This tools brings some utility
functions to try to simplify the process. It gives you access to 3
commands: Ls, Diff and Report

List the changed DB entry and know if the manifest or the image info was
updated easily. The tool also ignores by default the volatiles UUID so
you are not polluted by that during the review process.

Diff the changed files, either all of them one after the other or a
specific set given by the user. It will open a difftool (vimdiff by
default) to diff either the manifest or the image-info (or both if they
both changed).

Report the change as an ascii table with color codes (by default) or as
a github TODO list to be integrated within the github PR.

report generation

Terminal report

Github report

Listing changed DB entries

Diff all or a list of files

[ondrejbudai]

May I ask you for a quick example of the output? That would be very valuable to everyone having a look at this PR. :)

[lavocatt]

May I ask you for a quick example of the output? That would be very valuable to everyone having a look at this PR. :)

Good idea! I'll record my screen using it with peek and include the gifs inside the PR description and in the README also :)

[achilleas-k]

Added some comments in the diff function that apply to all places where the same code and logic is used.

[ondrejbudai]

Thanks a lot for the demos, they look really sleek. Some suggestions inline to make the code nicer.

@supakeen May I ask for your opinion on using some kind of templating? I'm still not sure if it improved readability, but I'm just not a fan of formatting text imperatively.

[supakeen]

@ondrejbudai I'll take a look later this morning, thanks.

[supakeen]

I like the way the formatting is structured now much more.

[ondrejbudai]

Looks much better, thanks! There are still some unresolved comments but they should be easy to fix. :)

[ondrejbudai]

One forgotten function, otherwise this is fine. :)