deposit: Remove 'parent' deposit

This diff un-reverts !230 (closed).

The parent is computed by the deposit as the revision of the latest deposit in the same origin before the current one. Therefore, it is redundant, as it can be recomputed from metadata

• revision date.

This is a preliminary change needed to make package loaders produce releases instead of revisions, as releases don't have parent relationships

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Migrated from D6600 (view on Phabricator)

Build is green

Patch application report for D6600 (id=23986)

Rebasing onto 5063082e...

Current branch diff-target is up to date.

Changes applied before test

commit 8ab9ae38ac44b216c1c86a0d53c018a1c4d7a02a
Author: Valentin Lorentz <vlorentz@softwareheritage.org>
Date:   Thu Oct 21 14:35:47 2021 +0200

    deposit: Remove 'parent' deposit
    
    The parent is computed by the deposit as the revision of the latest deposit
    in the same origin before the current one.
    Therefore, it is redundant, as it can be recomputed from metadata
    + revision date.
    
    This is a preliminary change needed to make package loaders produce
    releases instead of revisions, as releases don't have parent relationships

See https://jenkins.softwareheritage.org/job/DLDBASE/job/tests-on-diff/590/ for more details.

mentioned in merge request !237 (closed)

Merge request was accepted

approved this merge request

At that rate, I'm starting to wonder why we even bother with release/revision objects for deposits at all. If all substantial operations to understand their context need to go through the extrinsic metadata attached to the directory, we could just make the snapshot point to the directory directly?

The thing is, everything can be done using the extrinsic metadata storage instead of the main storage. But that means the data becomes less structured / schemaless, and I don't think that's a good thing.

f6905cdf

Merge request was merged

closed