[SPD-48307]: add DB repo test infrastructure + PacketDBRepository filter

[AdiDev0]

User description

What

Sets up the database repository testing infrastructure for tars and delivers
the first concrete example: PacketDBRepository.filter with full test coverage.

This PR is intentionally narrow — it exists to give every developer on the team
a working reference for how DB repo code and tests should be structured in tars,
mirroring the pattern used in django-rest-api.

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Changes

app/db/postgres.py — SoftDeleteMixin query entry points

Added two classmethods to SoftDeleteMixin, available on every model that
composes it (Packet, Agreement, LegalHub, etc.):

Packet.objects()                   # SELECT … WHERE is_deleted = false  (default)
Packet.objects_including_deleted() # SELECT … (all rows)

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# Generated description

Below is a concise technical summary of the changes proposed in this PR:
Establish SoftDeleteMixin query helpers and <code>PacketDBRepository.filter</code> so workspace-scoped packet retrieval respects soft deletes, optional ID constraints, and emits structured logs. Provide the pytest fixtures, base test case, factories, and concrete tests for <code>PacketDBRepository.filter</code>, mirroring django-rest-api conventions to document DB repo structure adoption.
<table><tr><th>Topic</th><th>Details</th><tr><td><a href=https://baz.co/changes/SpotDraft/tars/3?tool=ast&topic=Packet+filtering>Packet filtering</a>
        </td><td>Implement <code>PacketDBRepository.filter</code> plus SoftDeleteMixin helpers so packet retrieval honors workspace isolation, optional ID lists, soft-delete opt-in, and logging while exposing domain models for validation.<details><summary>Modified files (3)</summary><ul><li>app/clickwrap/data/postgres/db_repo.py</li>
<li>app/clickwrap/domain/domain_models.py</li>
<li>app/db/postgres.py</li></ul></details><details><summary>Latest Contributors(1)</summary><table><tr><th>User</th><th>Commit</th><th>Date</th></tr><tr><td>aditya.raj@spotdraft.com</td><td>[]: add DB repo test i...</td><td>July 08, 2026</td></tr></table></details></td></tr>
<tr><td><a href=https://baz.co/changes/SpotDraft/tars/3?tool=ast&topic=DB+repo+tests>DB repo tests</a>
        </td><td>Document the DB repo testing pattern via BaseDBRepoTestCase, pytest engine/session fixtures, Packet factories, and integration tests (with package init) that cover workspace boundaries, ID filtering, and soft delete behavior.<details><summary>Modified files (5)</summary><ul><li>tests/base_db_repo_test.py</li>
<li>tests/clickwrap/data/__init__.py</li>
<li>tests/clickwrap/data/test_packet_db_repo.py</li>
<li>tests/conftest.py</li>
<li>tests/factories.py</li></ul></details><details><summary>Latest Contributors(1)</summary><table><tr><th>User</th><th>Commit</th><th>Date</th></tr><tr><td>aditya.raj@spotdraft.com</td><td>[]: add DB repo test i...</td><td>July 08, 2026</td></tr></table></details></td></tr></table>
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[baz-reviewer]

Spec Reviewer Report

✅ 2 met requirements:

1. Test database configured for microservice testing

Pytest fixtures now set up a dedicated async test database with derived URL, schema creation, and session rollback support.

 Evidence:

 

• tests/conftest.py:18-25 derive TEST_DATABASE_URL from TEST_DATABASE_URL env or settings
• tests/conftest.py:33-45 test_engine fixture creates async engine against test DB, installs pg_trgm, creates/drops metadata each session
• tests/conftest.py:53-62 db_session fixture yields per-test AsyncSession with rollback cleanup

2. Basic database repositories provided for microservice

PacketDBRepository.filter now encapsulates workspace-scoped querying, optional ID filtering, and soft-delete opt-in so the microservice has a functioning repository layer.

 Evidence:

 

• app/clickwrap/data/postgres/db_repo.py:15-64 (PacketDBRepository.filter implements workspace isolation, ID filtering, soft-delete options, and logs results)
• app/clickwrap/domain/domain_models.py:7-38 (domain models define the request/response contracts used by the repository)
• tests/clickwrap/data/test_packet_db_repo.py:1-93 (integration tests covering workspace isolation, packet ID filtering, and soft-delete handling)

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Used resources:
Hash: f60bea0 | Ticket: [BE] Setup test db and basic db repos in microservice | Checkout in Baz

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