Add validation handling

Author: borys25ol

conduit/api/schemas/requests/comment.py

@@ -1,10 +1,10 @@
-from pydantic import BaseModel
+from pydantic import BaseModel, Field
 
 from conduit.domain.dtos.comment import CreateCommentDTO
 
 
 class CreateCommentData(BaseModel):
-    body: str
+    body: str = Field(..., min_length=1)
 
 
 class CreateCommentRequest(BaseModel):

conduit/api/schemas/requests/user.py

@@ -1,17 +1,17 @@
-from pydantic import BaseModel, Field
+from pydantic import BaseModel, EmailStr, Field
 
 from conduit.domain.dtos.user import CreateUserDTO, LoginUserDTO, UpdateUserDTO
 
 
 class UserRegistrationData(BaseModel):
-    email: str
-    password: str
-    username: str
+    email: EmailStr
+    password: str = Field(..., min_length=8)
+    username: str = Field(..., min_length=3)
 
 
 class UserLoginData(BaseModel):
-    email: str
-    password: str
+    email: EmailStr
+    password: str = Field(..., min_length=8)
 
 
 class UserUpdateData(BaseModel):

conduit/core/exceptions.py

@@ -1,9 +1,13 @@
+from typing import Any
+
 from fastapi import FastAPI
 from fastapi.exceptions import RequestValidationError
 from starlette.exceptions import HTTPException
 from starlette.requests import Request
 from starlette.responses import JSONResponse
 
+from conduit.core.utils.errors import format_errors
+
 
 class BaseInternalException(Exception):
     """
@@ -12,12 +16,13 @@ class BaseInternalException(Exception):
 
     _status_code = 0
     _message = ""
+    _errors: dict = {}
 
     def __init__(
         self,
         status_code: int | None = None,
         message: str | None = None,
-        errors: list[str] | None = None,
+        errors: dict[str, dict[Any, Any]] | None = None,
     ) -> None:
         self.status_code = status_code
         self.message = message
@@ -29,6 +34,9 @@ def get_status_code(self) -> int:
     def get_message(self) -> str:
         return self.message or self._message
 
+    def get_errors(self) -> dict[str, dict[Any, Any]]:
+        return self.errors or self._errors
+
     @classmethod
     def get_response(cls) -> JSONResponse:
         return JSONResponse(
@@ -38,6 +46,7 @@ def get_response(cls) -> JSONResponse:
                 "status_code": cls._status_code,
                 "type": cls.__name__,
                 "message": cls._message,
+                "errors": cls._errors,
             },
         )
 
@@ -96,20 +105,26 @@ class EmailAlreadyTakenException(BaseInternalException):
 
     _status_code = 400
     _message = "User with this email already exists."
+    _errors = {"email": ["user with this email already exists."]}
 
 
 class UserNameAlreadyTakenException(BaseInternalException):
     """Exception raised when username was found in database while registration."""
 
     _status_code = 400
     _message = "User with this username already exists."
+    _errors = {"username": ["user with this username already exists."]}
 
 
 class IncorrectLoginInputException(BaseInternalException):
     """Exception raised when email or password was incorrect while login."""
 
     _status_code = 400
     _message = "Incorrect email or password."
+    _errors = {
+        "email": ["incorrect email or password."],
+        "password": ["incorrect email or password."],
+    }
 
 
 class IncorrectJWTTokenException(BaseInternalException):
@@ -170,6 +185,7 @@ async def _exception_handler(
                 "status_code": exc.get_status_code(),
                 "type": type(exc).__name__,
                 "message": exc.get_message(),
+                "errors": exc.get_errors(),
             },
         )
 
@@ -190,7 +206,7 @@ async def _exception_handler(
                 "status_code": 422,
                 "type": "RequestValidationError",
                 "message": "Schema validation error",
-                "errors": exc.errors(),
+                "errors": format_errors(errors=exc.errors()),
             },
         )
 

conduit/core/utils/errors.py

@@ -1,4 +1,5 @@
-from collections.abc import Awaitable
+from collections import defaultdict
+from collections.abc import Awaitable, Sequence
 from typing import Any
 
 
@@ -10,3 +11,15 @@ async def get_or_raise(awaitable: Awaitable, exception: Exception) -> Any:
     if not result:
         raise exception
     return result
+
+
+def format_errors(errors: Sequence[Any]) -> dict[str, list[str]]:
+    """
+    Format errors from pydantic validation errors.
+    """
+    result: defaultdict[str, list[str]] = defaultdict(list)
+    for error in errors:
+        field = error["loc"][-1]
+        message = error.get("ctx", {}).get("reason") or error["msg"]
+        result[field].append(message.lower())
+    return dict(result)

requirements.txt

@@ -4,8 +4,8 @@ fastapi==0.115.4
 greenlet==3.1.1
 httpx==0.27.2
 passlib[bcrypt]==1.7.4
-pydantic==2.9.2
 pydantic-settings==2.6.1
+pydantic[email]==2.9.2
 pyjwt==2.9.0
 pytest==8.3.3
 pytest-asyncio==0.24.0