Drop dataclass usage in base entity

Author: ivan-borovets

src/app/domain/entities/base.py

@@ -1,4 +1,3 @@
-from dataclasses import dataclass
 from typing import Any, TypeVar
 
 from app.domain.exceptions.base import DomainError
@@ -7,29 +6,19 @@
 T = TypeVar("T", bound=ValueObject)
 
 
-@dataclass(eq=False)
 class Entity[T: ValueObject]:
     """
     raises DomainError
 
     Base class for domain entities, defined by a unique identity (`id`).
     - `id`: Identity that remains constant throughout the entity's lifecycle.
     - Entities are mutable, but are compared solely by their `id`.
-    - Subclasses must set `eq=False` to inherit the equality behavior.
-    - Add `kw_only=True` in subclasses to enforce named arguments for clarity & safety.
     """
 
-    id_: T
-
-    def __post_init__(self) -> None:
-        """
-        :raises DomainError:
-
-        Hook for additional initialization and ensuring invariants.
-        Subclasses can override this method to implement custom logic, while
-        still calling `super().__post_init__()` to preserve base checks.
-        """
+    def __init__(self, *, id_: T) -> None:
+        """:raises DomainError:"""
         self.__forbid_base_class_instantiation()
+        self.id_ = id_
 
     def __forbid_base_class_instantiation(self) -> None:
         """:raises DomainError:"""

src/app/domain/entities/user.py

@@ -1,15 +1,22 @@
-from dataclasses import dataclass
-
 from app.domain.entities.base import Entity
 from app.domain.enums.user_role import UserRole
 from app.domain.value_objects.user_id import UserId
 from app.domain.value_objects.user_password_hash import UserPasswordHash
 from app.domain.value_objects.username import Username
 
 
-@dataclass(eq=False, kw_only=True)
 class User(Entity[UserId]):
-    username: Username
-    password_hash: UserPasswordHash
-    role: UserRole
-    is_active: bool
+    def __init__(
+        self,
+        *,
+        id_: UserId,
+        username: Username,
+        password_hash: UserPasswordHash,
+        role: UserRole,
+        is_active: bool,
+    ) -> None:
+        super().__init__(id_=id_)
+        self.username = username
+        self.password_hash = password_hash
+        self.role = role
+        self.is_active = is_active

tests/app/unit/factories/named_entity.py

@@ -9,14 +9,16 @@ class NamedEntityId(ValueObject):
     value: int
 
 
-@dataclass(eq=False)
 class NamedEntity(Entity[NamedEntityId]):
-    name: str
+    def __init__(self, *, id_: NamedEntityId, name: str) -> None:
+        super().__init__(id_=id_)
+        self.name = name
 
 
-@dataclass(eq=False)
 class NamedEntitySubclass(NamedEntity):
-    value: int
+    def __init__(self, *, id_: NamedEntityId, name: str, value: int) -> None:
+        super().__init__(id_=id_, name=name)
+        self.value = value
 
 
 def create_named_entity_id(
@@ -29,12 +31,12 @@ def create_named_entity(
     id_: int = 42,
     name: str = "name",
 ) -> NamedEntity:
-    return NamedEntity(NamedEntityId(id_), name)
+    return NamedEntity(id_=NamedEntityId(id_), name=name)
 
 
 def create_named_entity_subclass(
     id_: int = 42,
     name: str = "name",
     value: int = 314,
 ) -> NamedEntitySubclass:
-    return NamedEntitySubclass(NamedEntityId(id_), name, value)
+    return NamedEntitySubclass(id_=NamedEntityId(id_), name=name, value=value)

tests/app/unit/factories/tagged_entity.py

@@ -9,19 +9,15 @@ class TaggedEntityId(ValueObject):
     value: int
 
 
-@dataclass(eq=False)
 class TaggedEntity(Entity[TaggedEntityId]):
-    tag: str
+    def __init__(self, *, id_: TaggedEntityId, tag: str) -> None:
+        super().__init__(id_=id_)
+        self.tag = tag
 
 
-def create_tagged_entity_id(
-    id_: int = 54,
-) -> TaggedEntityId:
+def create_tagged_entity_id(id_: int = 54) -> TaggedEntityId:
     return TaggedEntityId(id_)
 
 
-def create_tagged_entity(
-    id_: int = 54,
-    tag: str = "tag",
-) -> TaggedEntity:
-    return TaggedEntity(TaggedEntityId(id_), tag)
+def create_tagged_entity(id_: int = 54, tag: str = "tag") -> TaggedEntity:
+    return TaggedEntity(id_=TaggedEntityId(id_), tag=tag)