RemoteArtifacts checksum type check

[pavelpicka]

RemoteArtifacts are checked for forbidden checksums.

closes: #8423
https://pulp.plan.io/issues/8423

[pulpbot]

Attached issue: https://pulp.plan.io/issues/8423

[daviddavis]

The logic here is not quite correct. We want to allow a RemoteArtifact if it (1) has no checksums or (2) has an allowed checksum. So it can have forbidden checksum(s) if also has an allowed checksum. Something like this:

def validate_checksums(self):
    """Check that a RemoteArtifact either doesn't have checksums or has no allowed checksums.""""
    if len([c for c in ALL_KNOWN_CHECKSUMS if get_attr(self, c, False)]) == 0:
        # doesn't have any checksums
        return
    if len([c for c in Artifact.DIGEST_FIELDS if get_attr(self, c, False)]) == 0:
        # doesn't have any allowed checksums
        raise UnsupportedDigestValidationError("...")

[daviddavis]

Tests look good. Can you add a test that checks a RemoteArtifact with an allowed AND a forbidden checksum? It should not raise an exception.

[daviddavis]

I don't know if users know what RemoteArtifacts are. I would maybe say "On-demand content".

[daviddavis]

I would also include self.url in the message to help users track down the problem.

[pavelpicka]

Also changed in CHANGES message

[ipanova]

if i may suggest : On-demand content located at the url {}...

[ipanova]

in theory the AttributeError should never be raised

[pavelpicka]

in theory yes, but I'd rather stay explicit

[ipanova]

s/are checked/is checked/

[ipanova]

On-demand content is checked for forbidden checksum types and Pulp raises an exception when those are exclusively found.

[ipanova]

@daviddavis exclusively or solely?

[daviddavis]

Both work. I might even use something simpler: "Added sync check that raises error when only forbidden checksums are found for on-demand content".