Add support for pydantic v2 via pydantic.v1 compat module (#16332)

While maintaining support with pydantic v1.

12 files changed, 105 insertions, 15 deletions

diff --git a/synapse/_pydantic_compat.py b/synapse/_pydantic_compat.py
new file mode 100644
index 0000000000..ddff72afa1
--- /dev/null
+++ b/synapse/_pydantic_compat.py
@@ -0,0 +1,26 @@
+# Copyright 2023 Maxwell G <maxwell@gtmx.me>
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from packaging.version import Version
+
+try:
+    from pydantic import __version__ as pydantic_version
+except ImportError:
+    import importlib.metadata
+
+    pydantic_version = importlib.metadata.version("pydantic")
+
+HAS_PYDANTIC_V2: bool = Version(pydantic_version).major == 2
+
+__all__ = ("HAS_PYDANTIC_V2",)
diff --git a/synapse/config/_util.py b/synapse/config/_util.py
index acccca413b..746838eee3 100644
--- a/synapse/config/_util.py
+++ b/synapse/config/_util.py
@@ -11,10 +11,16 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from typing import Any, Dict, Type, TypeVar
+from typing import TYPE_CHECKING, Any, Dict, Type, TypeVar
 
 import jsonschema
-from pydantic import BaseModel, ValidationError, parse_obj_as
+
+from synapse._pydantic_compat import HAS_PYDANTIC_V2
+
+if TYPE_CHECKING or HAS_PYDANTIC_V2:
+    from pydantic.v1 import BaseModel, ValidationError, parse_obj_as
+else:
+    from pydantic import BaseModel, ValidationError, parse_obj_as
 
 from synapse.config._base import ConfigError
 from synapse.types import JsonDict, StrSequence
diff --git a/synapse/config/workers.py b/synapse/config/workers.py
index 6567fb6bb0..f1766088fc 100644
--- a/synapse/config/workers.py
+++ b/synapse/config/workers.py
@@ -15,10 +15,16 @@
 
 import argparse
 import logging
-from typing import Any, Dict, List, Optional, Union
+from typing import TYPE_CHECKING, Any, Dict, List, Optional, Union
 
 import attr
-from pydantic import BaseModel, Extra, StrictBool, StrictInt, StrictStr
+
+from synapse._pydantic_compat import HAS_PYDANTIC_V2
+
+if TYPE_CHECKING or HAS_PYDANTIC_V2:
+    from pydantic.v1 import BaseModel, Extra, StrictBool, StrictInt, StrictStr
+else:
+    from pydantic import BaseModel, Extra, StrictBool, StrictInt, StrictStr
 
 from synapse.config._base import (
     Config,
diff --git a/synapse/events/validator.py b/synapse/events/validator.py
index 5da50cb0d2..a637fadfab 100644
--- a/synapse/events/validator.py
+++ b/synapse/events/validator.py
@@ -12,10 +12,16 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import collections.abc
-from typing import List, Type, Union, cast
+from typing import TYPE_CHECKING, List, Type, Union, cast
 
 import jsonschema
-from pydantic import Field, StrictBool, StrictStr
+
+from synapse._pydantic_compat import HAS_PYDANTIC_V2
+
+if TYPE_CHECKING or HAS_PYDANTIC_V2:
+    from pydantic.v1 import Field, StrictBool, StrictStr
+else:
+    from pydantic import Field, StrictBool, StrictStr
 
 from synapse.api.constants import (
     MAX_ALIAS_LENGTH,
diff --git a/synapse/http/servlet.py b/synapse/http/servlet.py
index 5d79d31579..d9d5655c95 100644
--- a/synapse/http/servlet.py
+++ b/synapse/http/servlet.py
@@ -28,8 +28,15 @@ from typing import (
     overload,
 )
 
-from pydantic import BaseModel, MissingError, PydanticValueError, ValidationError
-from pydantic.error_wrappers import ErrorWrapper
+from synapse._pydantic_compat import HAS_PYDANTIC_V2
+
+if TYPE_CHECKING or HAS_PYDANTIC_V2:
+    from pydantic.v1 import BaseModel, MissingError, PydanticValueError, ValidationError
+    from pydantic.v1.error_wrappers import ErrorWrapper
+else:
+    from pydantic import BaseModel, MissingError, PydanticValueError, ValidationError
+    from pydantic.error_wrappers import ErrorWrapper
+
 from typing_extensions import Literal
 
 from twisted.web.server import Request
diff --git a/synapse/rest/client/account.py b/synapse/rest/client/account.py
index 49cd0805fd..e74a87af4d 100644
--- a/synapse/rest/client/account.py
+++ b/synapse/rest/client/account.py
@@ -18,7 +18,12 @@ import random
 from typing import TYPE_CHECKING, List, Optional, Tuple
 from urllib.parse import urlparse
 
-from pydantic import StrictBool, StrictStr, constr
+from synapse._pydantic_compat import HAS_PYDANTIC_V2
+
+if TYPE_CHECKING or HAS_PYDANTIC_V2:
+    from pydantic.v1 import StrictBool, StrictStr, constr
+else:
+    from pydantic import StrictBool, StrictStr, constr
 from typing_extensions import Literal
 
 from twisted.web.server import Request
diff --git a/synapse/rest/client/devices.py b/synapse/rest/client/devices.py
index 925f037743..80ae937921 100644
--- a/synapse/rest/client/devices.py
+++ b/synapse/rest/client/devices.py
@@ -17,7 +17,12 @@ import logging
 from http import HTTPStatus
 from typing import TYPE_CHECKING, List, Optional, Tuple
 
-from pydantic import Extra, StrictStr
+from synapse._pydantic_compat import HAS_PYDANTIC_V2
+
+if TYPE_CHECKING or HAS_PYDANTIC_V2:
+    from pydantic.v1 import Extra, StrictStr
+else:
+    from pydantic import Extra, StrictStr
 
 from synapse.api import errors
 from synapse.api.errors import NotFoundError, SynapseError, UnrecognizedRequestError
diff --git a/synapse/rest/client/directory.py b/synapse/rest/client/directory.py
index 570bb52747..82944ca711 100644
--- a/synapse/rest/client/directory.py
+++ b/synapse/rest/client/directory.py
@@ -15,7 +15,13 @@
 import logging
 from typing import TYPE_CHECKING, List, Optional, Tuple
 
-from pydantic import StrictStr
+from synapse._pydantic_compat import HAS_PYDANTIC_V2
+
+if TYPE_CHECKING or HAS_PYDANTIC_V2:
+    from pydantic.v1 import StrictStr
+else:
+    from pydantic import StrictStr
+
 from typing_extensions import Literal
 
 from twisted.web.server import Request
diff --git a/synapse/rest/client/models.py b/synapse/rest/client/models.py
index 3d7940b0fc..880f79473c 100644
--- a/synapse/rest/client/models.py
+++ b/synapse/rest/client/models.py
@@ -13,7 +13,12 @@
 # limitations under the License.
 from typing import TYPE_CHECKING, Dict, Optional
 
-from pydantic import Extra, StrictInt, StrictStr, constr, validator
+from synapse._pydantic_compat import HAS_PYDANTIC_V2
+
+if TYPE_CHECKING or HAS_PYDANTIC_V2:
+    from pydantic.v1 import Extra, StrictInt, StrictStr, constr, validator
+else:
+    from pydantic import Extra, StrictInt, StrictStr, constr, validator
 
 from synapse.rest.models import RequestBodyModel
 from synapse.util.threepids import validate_email
diff --git a/synapse/rest/key/v2/remote_key_resource.py b/synapse/rest/key/v2/remote_key_resource.py
index 0aaa838d04..48c47058db 100644
--- a/synapse/rest/key/v2/remote_key_resource.py
+++ b/synapse/rest/key/v2/remote_key_resource.py
@@ -16,7 +16,13 @@ import logging
 import re
 from typing import TYPE_CHECKING, Dict, Mapping, Optional, Set, Tuple
 
-from pydantic import Extra, StrictInt, StrictStr
+from synapse._pydantic_compat import HAS_PYDANTIC_V2
+
+if TYPE_CHECKING or HAS_PYDANTIC_V2:
+    from pydantic.v1 import Extra, StrictInt, StrictStr
+else:
+    from pydantic import StrictInt, StrictStr, Extra
+
 from signedjson.sign import sign_json
 
 from twisted.web.server import Request
diff --git a/synapse/rest/models.py b/synapse/rest/models.py
index d47de5c19e..de354a2135 100644
--- a/synapse/rest/models.py
+++ b/synapse/rest/models.py
@@ -11,7 +11,14 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from pydantic import BaseModel, Extra
+from typing import TYPE_CHECKING
+
+from synapse._pydantic_compat import HAS_PYDANTIC_V2
+
+if TYPE_CHECKING or HAS_PYDANTIC_V2:
+    from pydantic.v1 import BaseModel, Extra
+else:
+    from pydantic import BaseModel, Extra
 
 
 class RequestBodyModel(BaseModel):
diff --git a/synapse/storage/background_updates.py b/synapse/storage/background_updates.py
index 99ebd96f84..12829d3d7d 100644
--- a/synapse/storage/background_updates.py
+++ b/synapse/storage/background_updates.py
@@ -31,8 +31,8 @@ from typing import (
 )
 
 import attr
-from pydantic import BaseModel
 
+from synapse._pydantic_compat import HAS_PYDANTIC_V2
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.storage.engines import PostgresEngine
 from synapse.storage.types import Connection, Cursor
@@ -41,6 +41,11 @@ from synapse.util import Clock, json_encoder
 
 from . import engines
 
+if TYPE_CHECKING or HAS_PYDANTIC_V2:
+    from pydantic.v1 import BaseModel
+else:
+    from pydantic import BaseModel
+
 if TYPE_CHECKING:
     from synapse.server import HomeServer
     from synapse.storage.database import DatabasePool, LoggingTransaction