feat: harden campaign delivery and editing

tests/test_campaign_optimistic_concurrency.py

@@ -0,0 +1,168 @@
+from __future__ import annotations
+
+import tempfile
+import unittest
+from pathlib import Path
+from unittest.mock import patch
+
+from sqlalchemy import Column, String, Table, create_engine
+from sqlalchemy.orm import Session, sessionmaker
+
+from govoplan_campaign.backend.db.models import (
+    Campaign,
+    CampaignIssue,
+    CampaignVersion,
+)
+from govoplan_campaign.backend.persistence.versions import update_campaign_version
+from govoplan_core.core.change_sequence import ChangeSequenceEntry
+from govoplan_core.core.concurrency import RevisionConflictError
+from govoplan_core.db.base import Base
+
+
+class CampaignOptimisticConcurrencyTests(unittest.TestCase):
+    def setUp(self) -> None:
+        self.temp_dir = tempfile.TemporaryDirectory()
+        database_path = Path(self.temp_dir.name) / "campaign.db"
+        self.engine = create_engine(f"sqlite+pysqlite:///{database_path}")
+        access_users = Base.metadata.tables.get("access_users")
+        if access_users is None:
+            access_users = Table(
+                "access_users",
+                Base.metadata,
+                Column("id", String(36), primary_key=True),
+            )
+        access_groups = Base.metadata.tables.get("access_groups")
+        if access_groups is None:
+            access_groups = Table(
+                "access_groups",
+                Base.metadata,
+                Column("id", String(36), primary_key=True),
+            )
+        Base.metadata.create_all(
+            self.engine,
+            tables=[
+                access_users,
+                access_groups,
+                ChangeSequenceEntry.__table__,
+                Campaign.__table__,
+                CampaignVersion.__table__,
+                CampaignIssue.__table__,
+            ],
+        )
+        self.SessionLocal = sessionmaker(
+            bind=self.engine,
+            class_=Session,
+            expire_on_commit=False,
+        )
+        with self.SessionLocal() as session:
+            campaign = Campaign(
+                id="campaign-1",
+                tenant_id="tenant-1",
+                external_id="C-1",
+                name="Campaign",
+                current_version_id="version-1",
+            )
+            version = CampaignVersion(
+                id="version-1",
+                campaign_id=campaign.id,
+                version_number=1,
+                raw_json={
+                    "version": "1.0",
+                    "campaign": {
+                        "id": "C-1",
+                        "name": "Campaign",
+                        "description": "Base",
+                    },
+                },
+            )
+            session.add_all((campaign, version))
+            session.commit()
+        self.addCleanup(self.engine.dispose)
+        self.addCleanup(self.temp_dir.cleanup)
+
+    @staticmethod
+    def _update(
+        session: Session,
+        *,
+        expected_revision: int,
+        name: str,
+    ) -> CampaignVersion:
+        with (
+            patch(
+                "govoplan_campaign.backend.persistence.versions._updated_runtime_json",
+                side_effect=lambda _session, **kwargs: kwargs["raw_json"],
+            ),
+            patch(
+                "govoplan_campaign.backend.persistence.versions._write_campaign_snapshot"
+            ),
+        ):
+            return update_campaign_version(
+                session,
+                tenant_id="tenant-1",
+                campaign_id="campaign-1",
+                version_id="version-1",
+                raw_json={
+                    "version": "1.0",
+                    "campaign": {
+                        "id": "C-1",
+                        "name": name,
+                        "description": "Base",
+                    },
+                },
+                expected_revision=expected_revision,
+            )
+
+    def test_only_one_of_two_writers_can_commit_the_same_revision(self) -> None:
+        first = self.SessionLocal()
+        second = self.SessionLocal()
+        self.addCleanup(first.close)
+        self.addCleanup(second.close)
+        first.get(CampaignVersion, "version-1")
+        second.get(CampaignVersion, "version-1")
+
+        saved = self._update(
+            first,
+            expected_revision=1,
+            name="First writer",
+        )
+        self.assertEqual(saved.edit_revision, 2)
+
+        with self.assertRaises(RevisionConflictError) as raised:
+            self._update(
+                second,
+                expected_revision=1,
+                name="Second writer",
+            )
+        self.assertEqual(raised.exception.current_revision, 2)
+        self.assertEqual(raised.exception.submitted_base_revision, 1)
+
+        with self.SessionLocal() as verification:
+            current = verification.get(CampaignVersion, "version-1")
+            assert current is not None
+            self.assertEqual(current.raw_json["campaign"]["name"], "First writer")
+            self.assertEqual(current.edit_revision, 2)
+
+    def test_stale_revision_is_rejected_before_mutation(self) -> None:
+        with self.SessionLocal() as first:
+            self._update(
+                first,
+                expected_revision=1,
+                name="First writer",
+            )
+        with self.SessionLocal() as stale:
+            with self.assertRaises(RevisionConflictError):
+                self._update(
+                    stale,
+                    expected_revision=1,
+                    name="Stale writer",
+                )
+            stale.rollback()
+
+        with self.SessionLocal() as verification:
+            current = verification.get(CampaignVersion, "version-1")
+            assert current is not None
+            self.assertEqual(current.raw_json["campaign"]["name"], "First writer")
+
+
+if __name__ == "__main__":
+    unittest.main()