Vault Integration tests & QA

We need a way to do integration tests of the vault, and integrate them with monitoring+QA. It's not trivial to do so because we need a way to invalidate the vault cache everytime we cook the test object.

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Migrated from T1174 (view on Phabricator)

added System administration Vault priority:Normal labels

changed the description

We want to test the end-to-end functionalities of the vault. Various use cases should hence be tested:

1. requesting cooking of an object not in cache (this is the hard part @seirl was referring to)
2. requesting the download of an object in cache (this is easier, but should be tested nonetheless)
3. requesting the download of an object not in cache
4. requesting what's the current status of an object being cooked (or already done, or never requested)

a way to make it (1) simpler might be to have a blacklist of objects that should never be cached, for instance, a specific snapshot and/or dir of our helloworld repo

[ updated the message above in-place to add 3 and 4 ]

It would also be possible to add a parameter to force the recooking of an object, which would be more flexible to do a variety of tests on random "known" objects. This might require some thought about whether that would be a public option or not, and if not, how we would restrict its access.

We have an icinga plugin implementing some of this: https://forge.softwareheritage.org/source/swh-icinga-plugins/browse/master/swh/icinga_plugins/vault.py