fix: Add support for Pydantic v2.12 (#1471)

### Description

- Add support pydantic v2.12. This uses a workaround to ensure
compatibility with `Annotated[..., Field(default_factory=...)]` and with
type hints.

### Issues

- Closes: #1464

Author: Mantisus

pyproject.toml

@@ -40,7 +40,7 @@ dependencies = [
     "protego>=0.5.0",
     "psutil>=6.0.0",
     "pydantic-settings>=2.2.0,!=2.7.0,!=2.7.1,!=2.8.0",
-    "pydantic>=2.11.0,<2.12.0",
+    "pydantic>=2.11.0",
     "pyee>=9.0.0",
     "tldextract>=5.1.0",
     "typing-extensions>=4.1.0",

src/crawlee/_request.py

@@ -185,33 +185,44 @@ class Request(BaseModel):
     method: HttpMethod = 'GET'
     """HTTP request method."""
 
-    headers: Annotated[HttpHeaders, Field(default_factory=HttpHeaders)] = HttpHeaders()
-    """HTTP request headers."""
-
     payload: Annotated[
         HttpPayload | None,
         BeforeValidator(lambda v: v.encode() if isinstance(v, str) else v),
         PlainSerializer(lambda v: v.decode() if isinstance(v, bytes) else v),
     ] = None
     """HTTP request payload."""
 
-    user_data: Annotated[
-        dict[str, JsonSerializable],  # Internally, the model contains `UserData`, this is just for convenience
-        Field(alias='userData', default_factory=lambda: UserData()),
-        PlainValidator(user_data_adapter.validate_python),
-        PlainSerializer(
-            lambda instance: user_data_adapter.dump_python(
-                instance,
-                by_alias=True,
-                exclude_none=True,
-                exclude_unset=True,
-                exclude_defaults=True,
-            )
-        ),
-    ] = {}
-    """Custom user data assigned to the request. Use this to save any request related data to the
-    request's scope, keeping them accessible on retries, failures etc.
-    """
+    # Workaround for pydantic 2.12 and mypy type checking issue for Annotated with default_factory
+    if TYPE_CHECKING:
+        headers: HttpHeaders = HttpHeaders()
+        """HTTP request headers."""
+
+        user_data: dict[str, JsonSerializable] = {}
+        """Custom user data assigned to the request. Use this to save any request related data to the
+        request's scope, keeping them accessible on retries, failures etc.
+        """
+
+    else:
+        headers: Annotated[HttpHeaders, Field(default_factory=HttpHeaders)]
+        """HTTP request headers."""
+
+        user_data: Annotated[
+            dict[str, JsonSerializable],  # Internally, the model contains `UserData`, this is just for convenience
+            Field(alias='userData', default_factory=lambda: UserData()),
+            PlainValidator(user_data_adapter.validate_python),
+            PlainSerializer(
+                lambda instance: user_data_adapter.dump_python(
+                    instance,
+                    by_alias=True,
+                    exclude_none=True,
+                    exclude_unset=True,
+                    exclude_defaults=True,
+                )
+            ),
+        ]
+        """Custom user data assigned to the request. Use this to save any request related data to the
+        request's scope, keeping them accessible on retries, failures etc.
+        """
 
     retry_count: Annotated[int, Field(alias='retryCount')] = 0
     """Number of times the request has been retried."""

src/crawlee/_types.py

@@ -3,17 +3,7 @@
 import dataclasses
 from collections.abc import Callable, Iterator, Mapping
 from dataclasses import dataclass
-from typing import (
-    TYPE_CHECKING,
-    Annotated,
-    Any,
-    Literal,
-    Protocol,
-    TypedDict,
-    TypeVar,
-    cast,
-    overload,
-)
+from typing import TYPE_CHECKING, Annotated, Any, Literal, Protocol, TypedDict, TypeVar, cast, overload
 
 from pydantic import ConfigDict, Field, PlainValidator, RootModel
 
@@ -71,11 +61,15 @@ class HttpHeaders(RootModel, Mapping[str, str]):
 
     model_config = ConfigDict(validate_by_name=True, validate_by_alias=True)
 
-    root: Annotated[
-        dict[str, str],
-        PlainValidator(lambda value: _normalize_headers(value)),
-        Field(default_factory=dict),
-    ] = {}
+    # Workaround for pydantic 2.12 and mypy type checking issue for Annotated with default_factory
+    if TYPE_CHECKING:
+        root: dict[str, str] = {}
+    else:
+        root: Annotated[
+            dict[str, str],
+            PlainValidator(lambda value: _normalize_headers(value)),
+            Field(default_factory=dict),
+        ]
 
     def __getitem__(self, key: str) -> str:
         return self.root[key.lower()]