docs: define CardDAV credential deletion

README.md

@@ -43,6 +43,13 @@ inspection UI are implemented. The conflict review UI compares stored local and
 remote field payloads, can apply a stored remote vCard payload, and supports
 manual per-field local/remote merge choices.
 
+API-managed CardDAV credentials are encrypted inside the source record. Source
+deletion physically removes that credential material and records a non-secret
+audit event in the same database transaction; destructive module retirement
+audits every remaining credential before the owning tables are dropped. Legacy
+external references are detached but are never sent to a secret provider for
+deletion because Addresses cannot prove that it owns them.
+
 ## Boundary
 
 `govoplan-addresses` owns:

docs/ADDRESS_MODULE_ARCHITECTURE.md

@@ -148,7 +148,12 @@ a conflict instead of silently overwriting remote data. The first conflict
 review UI compares stored local and remote field payloads and can apply a
 stored remote vCard payload or a manual per-field local/remote merge payload.
 Source disconnect/delete removes the source binding and related sync records
-while keeping local contacts.
+while keeping local contacts. Because API-managed CardDAV credentials are
+encrypted in the source row, the same transaction physically removes their
+ciphertext and emits non-secret credential-deletion audit evidence. Destructive
+module retirement audits all remaining owned credential material before table
+removal. An unowned legacy reference is detached rather than passed to an
+external secret provider.
 
 ## Connector Direction
 

src/govoplan_addresses/backend/manifest.py

@@ -1,7 +1,10 @@
 from __future__ import annotations
 
+from dataclasses import replace
 from pathlib import Path
 
+from sqlalchemy import inspect
+
 from govoplan_addresses.backend.capabilities import (
     CAPABILITY_ADDRESSES_CONTACT_WRITER,
     CAPABILITY_ADDRESSES_LOOKUP,
@@ -25,6 +28,47 @@ from govoplan_core.core.modules import (
 from govoplan_core.db.base import Base
 
 
+_addresses_table_retirement_provider = drop_table_retirement_provider(
+    addresses_models.AddressSyncDiagnostic,
+    addresses_models.AddressSyncConflict,
+    addresses_models.AddressSyncTombstone,
+    addresses_models.AddressSyncSource,
+    addresses_models.AddressListEntry,
+    addresses_models.AddressList,
+    addresses_models.ContactPostalAddress,
+    addresses_models.ContactPhone,
+    addresses_models.ContactEmail,
+    addresses_models.Contact,
+    addresses_models.AddressBook,
+    label="Addresses",
+)
+
+
+def _addresses_retirement_provider(session: object | None, module_id: str):
+    plan = _addresses_table_retirement_provider(session, module_id)
+    base_executor = plan.destroy_data_executor
+    if base_executor is None:
+        return plan
+
+    def executor(execute_session: object, execute_module_id: str) -> None:
+        if not hasattr(execute_session, "get_bind") or not hasattr(execute_session, "query"):
+            raise RuntimeError("No database session is available for Addresses credential retirement.")
+        if inspect(execute_session.get_bind()).has_table(addresses_models.AddressSyncSource.__tablename__):
+            from govoplan_addresses.backend.service import audit_address_credentials_for_retirement
+
+            audit_address_credentials_for_retirement(execute_session)
+        base_executor(execute_session, execute_module_id)
+
+    return replace(
+        plan,
+        destroy_data_warnings=(
+            *plan.destroy_data_warnings,
+            "Addresses-owned encrypted connector credentials are audited and deleted with the sync-source table.",
+        ),
+        destroy_data_executor=executor,
+    )
+
+
 def _permission(scope: str, label: str, description: str) -> PermissionDefinition:
     module_id, resource, action = scope.split(":", 2)
     return PermissionDefinition(
@@ -128,20 +172,7 @@ manifest = ModuleManifest(
         metadata=Base.metadata,
         script_location=str(Path(__file__).with_name("migrations") / "versions"),
         retirement_supported=True,
-        retirement_provider=drop_table_retirement_provider(
+        retirement_provider=_addresses_retirement_provider,
-            addresses_models.AddressSyncDiagnostic,
-            addresses_models.AddressSyncConflict,
-            addresses_models.AddressSyncTombstone,
-            addresses_models.AddressSyncSource,
-            addresses_models.AddressListEntry,
-            addresses_models.AddressList,
-            addresses_models.ContactPostalAddress,
-            addresses_models.ContactPhone,
-            addresses_models.ContactEmail,
-            addresses_models.Contact,
-            addresses_models.AddressBook,
-            label="Addresses",
-        ),
         retirement_notes="Destructive retirement drops address-owned database tables after the installer captures a database snapshot.",
     ),
     capability_factories={

src/govoplan_addresses/backend/service.py

@@ -12,6 +12,7 @@ from sqlalchemy import and_, false, func, or_
 from sqlalchemy.orm import Session
 
 from govoplan_core.auth import ApiPrincipal
+from govoplan_core.audit.logging import audit_event
 from govoplan_core.core.change_sequence import record_change
 from govoplan_core.db.base import utcnow
 from govoplan_core.security.secrets import decrypt_secret, encrypt_secret
@@ -352,9 +353,89 @@ def delete_sync_source(session: Session, principal: ApiPrincipal, sync_source_id
         book.sync_status = None
         book.sync_error = None
         book.updated_by_account_id = _account_id(principal)
+    _audit_sync_credential_deletion(session, principal, sync_source)
     session.delete(sync_source)
 
 
+def _audit_sync_credential_deletion(
+    session: Session,
+    principal: ApiPrincipal,
+    sync_source: AddressSyncSource,
+) -> None:
+    """Audit removal of source-owned credential material in the DB transaction.
+
+    CardDAV credentials are encrypted inside the sync-source row. Deleting that
+    row therefore deletes the credential atomically with the connector. Legacy
+    credential references are detached from the source, but are never resolved
+    or sent to an external provider because ownership cannot be proven.
+    """
+
+    tenant_id = _tenant_id_or_none(principal)
+    user = getattr(principal, "user", None)
+    _record_sync_credential_deletion_audit(
+        session,
+        sync_source=sync_source,
+        tenant_id=tenant_id,
+        user_id=getattr(user, "id", None),
+        api_key_id=getattr(principal, "api_key_id", None),
+        deletion_reason="sync_source_deleted",
+    )
+
+
+def _record_sync_credential_deletion_audit(
+    session: Session,
+    *,
+    sync_source: AddressSyncSource,
+    tenant_id: str | None,
+    user_id: str | None,
+    api_key_id: str | None,
+    deletion_reason: str,
+) -> bool:
+    auth = _carddav_auth_metadata(sync_source.metadata_)
+    if auth.get("secret_encrypted"):
+        storage_backend = "encrypted_database"
+    elif auth.get("credential_ref"):
+        storage_backend = "legacy_reference"
+    else:
+        return False
+    audit_event(
+        session,
+        tenant_id=tenant_id,
+        user_id=user_id,
+        api_key_id=api_key_id,
+        action="addresses.sync_credential_deleted",
+        scope="tenant" if tenant_id is not None else "system",
+        object_type="address_sync_credential",
+        object_id=sync_source.id,
+        details={
+            "sync_source_id": sync_source.id,
+            "connector_type": sync_source.connector_type,
+            "storage_backend": storage_backend,
+            "deletion_reason": deletion_reason,
+        },
+    )
+    return True
+
+
+def audit_address_credentials_for_retirement(session: Session) -> int:
+    """Audit credentials that the ensuing destructive table drop deletes."""
+
+    sources = session.query(AddressSyncSource).order_by(AddressSyncSource.id.asc()).all()
+    audited = 0
+    for source in sources:
+        if _record_sync_credential_deletion_audit(
+            session,
+            sync_source=source,
+            tenant_id=source.tenant_id,
+            user_id=None,
+            api_key_id=None,
+            deletion_reason="module_data_retired",
+        ):
+            audited += 1
+    session.flush()
+    return audited
+
+
 def start_sync_attempt(session: Session, principal: ApiPrincipal, sync_source_id: str) -> AddressSyncSource:
     sync_source = get_visible_sync_source(session, principal, sync_source_id)
     if not sync_source.enabled:

tests/test_addresses_service.py

@@ -3,7 +3,7 @@ from __future__ import annotations
 import unittest
 from unittest.mock import patch
 
-from sqlalchemy import create_engine
+from sqlalchemy import create_engine, inspect
 from sqlalchemy.orm import sessionmaker
 
 from govoplan_core.core.change_sequence import ChangeSequenceEntry
@@ -1051,6 +1051,107 @@ END:VCARD
         self.assertFalse(book.read_only)
         self.assertEqual([item.id for item in list_contacts(self.session, self.principal, address_book_id=book.id)], [contact.id])
 
+    def test_delete_sync_source_deletes_and_audits_encrypted_credential_atomically(self) -> None:
+        book = create_address_book(
+            self.session,
+            self.principal,
+            AddressBookCreateRequest(scope_type="user", name="Audited remote"),
+        )
+        self.session.commit()
+        self.session.refresh(book)
+        source = create_carddav_sync_source(
+            self.session,
+            self.principal,
+            book.id,
+            AddressCardDavSourceCreateRequest(
+                collection_url="https://carddav.example.local/addressbooks/audited/",
+                auth_type="basic",
+                username="ada",
+                password="do-not-audit-this",
+            ),
+        )
+        self.session.commit()
+        source_id = source.id
+
+        with patch("govoplan_addresses.backend.service.audit_event") as audit:
+            delete_sync_source(self.session, self.principal, source_id)
+            self.session.commit()
+
+        self.assertIsNone(self.session.get(AddressSyncSource, source_id))
+        audit.assert_called_once()
+        audit_call = audit.call_args.kwargs
+        self.assertEqual(audit_call["action"], "addresses.sync_credential_deleted")
+        self.assertEqual(audit_call["object_id"], source_id)
+        self.assertEqual(audit_call["details"]["storage_backend"], "encrypted_database")
+        self.assertNotIn("credential_ref", audit_call["details"])
+        self.assertNotIn("secret_encrypted", audit_call["details"])
+        self.assertNotIn("do-not-audit-this", repr(audit_call))
+
+    def test_delete_sync_source_is_not_staged_when_credential_audit_fails(self) -> None:
+        book = create_address_book(
+            self.session,
+            self.principal,
+            AddressBookCreateRequest(scope_type="user", name="Audit failure"),
+        )
+        self.session.commit()
+        self.session.refresh(book)
+        source = create_carddav_sync_source(
+            self.session,
+            self.principal,
+            book.id,
+            AddressCardDavSourceCreateRequest(
+                collection_url="https://carddav.example.local/addressbooks/audit-failure/",
+                auth_type="bearer",
+                bearer_token="do-not-audit-this",
+            ),
+        )
+        self.session.commit()
+
+        with patch(
+            "govoplan_addresses.backend.service.audit_event",
+            side_effect=RuntimeError("audit unavailable"),
+        ), self.assertRaisesRegex(RuntimeError, "audit unavailable"):
+            delete_sync_source(self.session, self.principal, source.id)
+
+        self.session.rollback()
+        persisted = self.session.get(AddressSyncSource, source.id)
+        self.assertIsNotNone(persisted)
+        self.assertIn("secret_encrypted", (persisted.metadata_ or {})["carddav"])
+
+    def test_destructive_module_retirement_audits_credentials_before_tables_are_dropped(self) -> None:
+        book = create_address_book(
+            self.session,
+            self.principal,
+            AddressBookCreateRequest(scope_type="user", name="Retired module"),
+        )
+        self.session.commit()
+        self.session.refresh(book)
+        source = create_carddav_sync_source(
+            self.session,
+            self.principal,
+            book.id,
+            AddressCardDavSourceCreateRequest(
+                collection_url="https://carddav.example.local/addressbooks/module-retirement/",
+                auth_type="bearer",
+                bearer_token="do-not-audit-this",
+            ),
+        )
+        self.session.commit()
+        source_id = source.id
+        retirement_provider = manifest.migration_spec.retirement_provider
+        assert retirement_provider is not None
+        plan = retirement_provider(self.session, "addresses")
+        assert plan.destroy_data_executor is not None
+
+        with patch("govoplan_addresses.backend.service.audit_event") as audit:
+            plan.destroy_data_executor(self.session, "addresses")
+
+        audit.assert_called_once()
+        audit_call = audit.call_args.kwargs
+        self.assertEqual(audit_call["object_id"], source_id)
+        self.assertEqual(audit_call["details"]["deletion_reason"], "module_data_retired")
+        self.assertNotIn("do-not-audit-this", repr(audit_call))
+        self.assertFalse(inspect(self.engine).has_table("addresses_sync_sources"))
 
 if __name__ == "__main__":
     unittest.main()