feat: add idempotent producer publication

tests/test_lifecycle.py

@@ -14,12 +14,15 @@ from govoplan_core.core.datasources import (
     DatasourceOrigin,
     DatasourceOriginReadRequest,
     DatasourceOriginReadResult,
+    DatasourcePublicationRequest,
     DatasourceReadRequest,
     DatasourceStageInput,
+    DatasourceValidationError,
 )
 from govoplan_core.db.base import Base, utcnow
 from govoplan_datasources.backend.db.models import (
     DatasourceMaterializationRecord,
+    DatasourcePublicationRecord,
     DatasourceRecord,
     DatasourceStageRecord,
 )
@@ -136,6 +139,7 @@ class DatasourceLifecycleTests(unittest.TestCase):
                 DatasourceRecord.__table__,
                 DatasourceMaterializationRecord.__table__,
                 DatasourceStageRecord.__table__,
+                DatasourcePublicationRecord.__table__,
             ],
         )
         self.Session = sessionmaker(bind=self.engine)
@@ -151,6 +155,7 @@ class DatasourceLifecycleTests(unittest.TestCase):
             self.engine,
             tables=[
                 DatasourceStageRecord.__table__,
+                DatasourcePublicationRecord.__table__,
                 DatasourceMaterializationRecord.__table__,
                 DatasourceRecord.__table__,
             ],
@@ -346,6 +351,85 @@ class DatasourceLifecycleTests(unittest.TestCase):
             tuple(item.ref for item in self.provider.list_stages(self.session, writer)),
         )
 
+    def test_producer_publication_is_atomic_idempotent_and_addressable(self) -> None:
+        producer = principal(scopes=())
+        request = DatasourcePublicationRequest(
+            producer_module="dataflow",
+            producer_run_ref="dataflow-run:run-1",
+            idempotency_key="monthly-output-2026-07",
+            name="Monthly comparison result",
+            source_name="monthly_comparison_result",
+            rows=(
+                {"case_id": "A-1", "result": "match"},
+                {"case_id": "A-2", "result": "review"},
+            ),
+            freeze=True,
+            frozen_label="July 2026",
+            provenance={"pipeline_revision": 3},
+        )
+
+        first = self.provider.publish_rows(
+            self.session,
+            producer,
+            request=request,
+        )
+        replay = self.provider.publish_rows(
+            self.session,
+            producer,
+            request=request,
+        )
+        second = self.provider.publish_rows(
+            self.session,
+            producer,
+            request=DatasourcePublicationRequest(
+                producer_module="dataflow",
+                producer_run_ref="dataflow-run:run-2",
+                idempotency_key="monthly-output-2026-08",
+                target_datasource_ref=first.datasource.ref,
+                rows=({"case_id": "A-3", "result": "match"},),
+            ),
+        )
+        self.session.commit()
+
+        self.assertFalse(first.replayed)
+        self.assertTrue(replay.replayed)
+        self.assertEqual(first.ref, replay.ref)
+        self.assertEqual(first.materialization.ref, replay.materialization.ref)
+        self.assertIsNotNone(first.materialization.frozen_at)
+        self.assertEqual(1, first.materialization.revision)
+        self.assertEqual(2, second.materialization.revision)
+        self.assertEqual(first.datasource.ref, second.datasource.ref)
+        self.assertEqual(
+            2,
+            self.session.query(DatasourcePublicationRecord).count(),
+        )
+
+    def test_publication_idempotency_key_rejects_different_output(self) -> None:
+        producer = principal(scopes=())
+        base = DatasourcePublicationRequest(
+            producer_module="dataflow",
+            producer_run_ref="dataflow-run:run-1",
+            idempotency_key="stable-key",
+            name="Result",
+            source_name="result",
+            rows=({"id": 1},),
+        )
+        self.provider.publish_rows(self.session, producer, request=base)
+
+        with self.assertRaises(DatasourceValidationError):
+            self.provider.publish_rows(
+                self.session,
+                producer,
+                request=DatasourcePublicationRequest(
+                    producer_module="dataflow",
+                    producer_run_ref="dataflow-run:run-1",
+                    idempotency_key="stable-key",
+                    name="Result",
+                    source_name="result",
+                    rows=({"id": 2},),
+                ),
+            )
+
 
 if __name__ == "__main__":
     unittest.main()

tests/test_manifest.py

@@ -5,6 +5,7 @@ import unittest
 from govoplan_core.core.datasources import (
     CAPABILITY_DATASOURCE_CATALOGUE,
     CAPABILITY_DATASOURCE_LIFECYCLE,
+    CAPABILITY_DATASOURCE_PUBLICATION,
 )
 from govoplan_datasources.backend.manifest import get_manifest
 
@@ -16,6 +17,10 @@ class DatasourceManifestTests(unittest.TestCase):
         self.assertEqual(manifest.id, "datasources")
         self.assertIn(CAPABILITY_DATASOURCE_CATALOGUE, manifest.capability_factories)
         self.assertIn(CAPABILITY_DATASOURCE_LIFECYCLE, manifest.capability_factories)
+        self.assertIn(
+            CAPABILITY_DATASOURCE_PUBLICATION,
+            manifest.capability_factories,
+        )
         self.assertIn(
             "datasources.materializations",
             {item.name for item in manifest.provides_interfaces},

tests/test_migrations.py

@@ -24,13 +24,14 @@ class DatasourceMigrationTests(unittest.TestCase):
             try:
                 with engine.connect() as connection:
                     self.assertIn(
-                        "f3a8d2c7b1e0",
+                        "c4e9f1a7d2b6",
                         set(MigrationContext.configure(connection).get_current_heads()),
                     )
                     self.assertEqual(
                         {
                             "datasource_catalogue",
                             "datasource_materializations",
+                            "datasource_publications",
                             "datasource_stages",
                         },
                         {