feat: add docs and custom exc

src/application/commands/create_kyc_command.py

@@ -3,7 +3,7 @@ from datetime import datetime,timedelta,timezone
 from src.application.abstractions import IUnitOfWork
 from src.application.contracts import IBeorgService,ILogger
 from src.application.domain.dto import BeorgKycCreateResponse,BeorgKycResultResponse,KycSessionResponse
-from src.application.domain.exceptions import ApplicationException
+from src.application.domain.exceptions import ApplicationException,KycFailedException,KycNotCompletedException,KycSessionExpiredException,KycSessionMissingUserTokenException
 from src.application.services import ensure_adult,extract_personal_data,parse_birth_date
 
 
@@ -58,11 +58,11 @@ class CompleteKycCommand:
     async def __call__(self,user_id: str) -> BeorgKycResultResponse:
         session = await self._get_session(user_id)
         if not session.user_token:
-            raise ApplicationException(status_code=409,message='KYC session has no user token')
+            raise KycSessionMissingUserTokenException()
 
         result = await self._beorg_service.get_result(user_token=session.user_token)
         if result.done_state is None:
-            raise ApplicationException(status_code=409,message='KYC is not completed yet')
+            raise KycNotCompletedException()
         if result.done_state is False:
             async with self._unit_of_work as unit_of_work:
                 await unit_of_work.kyc_repository.update_session_result(
@@ -74,7 +74,7 @@ class CompleteKycCommand:
                     result_data=result.data,
                     error='KYC failed',
                 )
-            raise ApplicationException(status_code=400,message='KYC failed')
+            raise KycFailedException()
 
         personal_data = extract_personal_data(result.data)
         birth_date = parse_birth_date(personal_data.birth_date)
@@ -115,7 +115,7 @@ class CompleteKycCommand:
                 client_user_token=session.client_user_token,
                 qr_code=session.qr_code,
             )
-        raise ApplicationException(status_code=404,message='KYC session expired')
+        raise KycSessionExpiredException()
 
 
 class GetKycSessionCommand:
@@ -134,7 +134,7 @@ class GetKycSessionCommand:
             await unit_of_work.kyc_repository.expire_started_sessions(user_id=user_id,now=now)
             session = await unit_of_work.kyc_repository.get_latest_session(user_id=user_id)
         if session is None or session.expires_at is None:
-            raise ApplicationException(status_code=404,message='KYC session expired')
+            raise KycSessionExpiredException()
 
         expires_in = max(int((session.expires_at - now).total_seconds()),0)
         return KycSessionResponse(

src/application/domain/exceptions/__init__.py

@@ -1 +1,2 @@
 from src.application.domain.exceptions.application_exceptions import ApplicationException
+from src.application.domain.exceptions.kyc_exceptions import BeorgConfigException,BeorgRejectedException,BeorgUnavailableException,CsrfRequestRequiredException,InvalidTokenException,JwtDecodeFailedException,KycAgeRestrictedException,KycBirthDateInvalidException,KycFailedException,KycNotCompletedException,KycPersonalDataIncompleteException,KycSessionExpiredException,KycSessionMissingUserTokenException,NotAuthenticatedException,UnauthorizedException,UserNotFoundException

src/application/domain/exceptions/application_exceptions.py

@@ -7,11 +7,13 @@ class ApplicationException(Exception):
         self,
         status_code: int,
         message: str,
+        error_code: str = 'application_error',
         headers: Mapping[str, str] | None = None,
     ):
         super().__init__(message)
         self.status_code = status_code
         self.message = message
+        self.error_code = error_code
         self.headers = headers
 
     def __str__(self):

src/application/domain/exceptions/kyc_exceptions.py

@@ -0,0 +1,98 @@
+from __future__ import annotations
+from src.application.domain.exceptions.application_exceptions import ApplicationException
+
+
+class UnauthorizedException(ApplicationException):
+
+    def __init__(self,message: str = 'Unauthorized') -> None:
+        super().__init__(status_code=401,message=message,error_code='unauthorized')
+
+
+class NotAuthenticatedException(ApplicationException):
+
+    def __init__(self) -> None:
+        super().__init__(status_code=401,message='Not authenticated',error_code='not_authenticated')
+
+
+class InvalidTokenException(ApplicationException):
+
+    def __init__(self,message: str = 'Invalid token') -> None:
+        super().__init__(status_code=401,message=message,error_code='invalid_token')
+
+
+class JwtDecodeFailedException(ApplicationException):
+
+    def __init__(self) -> None:
+        super().__init__(status_code=500,message='JWT decode failed',error_code='jwt_decode_failed')
+
+
+class CsrfRequestRequiredException(ApplicationException):
+
+    def __init__(self) -> None:
+        super().__init__(status_code=500,message='Request is required for CSRF protection',error_code='csrf_request_required')
+
+
+class UserNotFoundException(ApplicationException):
+
+    def __init__(self) -> None:
+        super().__init__(status_code=404,message='User not found',error_code='user_not_found')
+
+
+class KycSessionMissingUserTokenException(ApplicationException):
+
+    def __init__(self) -> None:
+        super().__init__(status_code=409,message='KYC session has no user token',error_code='kyc_session_missing_user_token')
+
+
+class KycNotCompletedException(ApplicationException):
+
+    def __init__(self) -> None:
+        super().__init__(status_code=409,message='KYC is not completed yet',error_code='kyc_not_completed')
+
+
+class KycFailedException(ApplicationException):
+
+    def __init__(self) -> None:
+        super().__init__(status_code=400,message='KYC failed',error_code='kyc_failed')
+
+
+class KycSessionExpiredException(ApplicationException):
+
+    def __init__(self) -> None:
+        super().__init__(status_code=404,message='KYC session expired',error_code='kyc_session_expired')
+
+
+class KycPersonalDataIncompleteException(ApplicationException):
+
+    def __init__(self) -> None:
+        super().__init__(status_code=422,message='KYC personal data is incomplete',error_code='kyc_personal_data_incomplete')
+
+
+class KycBirthDateInvalidException(ApplicationException):
+
+    def __init__(self) -> None:
+        super().__init__(status_code=422,message='KYC birth date has invalid format',error_code='kyc_birth_date_invalid')
+
+
+class KycAgeRestrictedException(ApplicationException):
+
+    def __init__(self) -> None:
+        super().__init__(status_code=403,message='KYC is unavailable for users under 18',error_code='kyc_age_restricted')
+
+
+class BeorgUnavailableException(ApplicationException):
+
+    def __init__(self) -> None:
+        super().__init__(status_code=502,message='Beorg service unavailable',error_code='beorg_unavailable')
+
+
+class BeorgRejectedException(ApplicationException):
+
+    def __init__(self,message: str = 'Beorg rejected kyc request') -> None:
+        super().__init__(status_code=400,message=message,error_code='beorg_rejected')
+
+
+class BeorgConfigException(ApplicationException):
+
+    def __init__(self) -> None:
+        super().__init__(status_code=500,message='Beorg service is not configured',error_code='beorg_not_configured')

src/application/services/kyc_personal_data.py

@@ -2,7 +2,7 @@ from __future__ import annotations
 from datetime import date,datetime
 from typing import Any
 from src.application.domain.dto import KycPersonalData
-from src.application.domain.exceptions import ApplicationException
+from src.application.domain.exceptions import KycAgeRestrictedException,KycBirthDateInvalidException,KycPersonalDataIncompleteException
 
 
 FIELD_ALIASES = {
@@ -33,7 +33,7 @@ def extract_personal_data(data: Any) -> KycPersonalData:
 
     missing = [field for field in ('first_name','last_name','birth_date') if not values.get(field)]
     if missing:
-        raise ApplicationException(status_code=422,message='KYC personal data is incomplete')
+        raise KycPersonalDataIncompleteException()
 
     return KycPersonalData(
         first_name=values['first_name'],
@@ -51,7 +51,7 @@ def ensure_adult(birth_date: date) -> None:
     except ValueError:
         adult_from = date(today.year - 18,2,28)
     if birth_date > adult_from:
-        raise ApplicationException(status_code=403,message='KYC is unavailable for users under 18')
+        raise KycAgeRestrictedException()
 
 
 def parse_birth_date(value: str) -> date:
@@ -84,4 +84,4 @@ def _parse_date(value: str) -> date:
             return datetime.strptime(clean,date_format).date()
         except ValueError:
             continue
-    raise ApplicationException(status_code=422,message='KYC birth date has invalid format')
+    raise KycBirthDateInvalidException()

src/infrastructure/beorg/client.py

@@ -3,7 +3,7 @@ from typing import Any
 import aiohttp
 from src.application.contracts import IBeorgService
 from src.application.domain.dto import BeorgKycCreateResponse,BeorgKycResultResponse
-from src.application.domain.exceptions import ApplicationException
+from src.application.domain.exceptions import BeorgConfigException,BeorgRejectedException,BeorgUnavailableException
 
 
 class BeorgService(IBeorgService):
@@ -49,11 +49,11 @@ class BeorgService(IBeorgService):
                 data = await response.json(content_type=None)
 
         if response.status >= 500:
-            raise ApplicationException(status_code=502,message='Beorg service unavailable')
+            raise BeorgUnavailableException()
 
         result = BeorgKycCreateResponse.model_validate(data)
         if not result.status:
-            raise ApplicationException(status_code=400,message=result.error or 'Beorg rejected kyc request')
+            raise BeorgRejectedException(result.error or 'Beorg rejected kyc request')
 
         return result
 
@@ -73,11 +73,11 @@ class BeorgService(IBeorgService):
                 data = await response.json(content_type=None)
 
         if response.status >= 500:
-            raise ApplicationException(status_code=502,message='Beorg service unavailable')
+            raise BeorgUnavailableException()
 
         return BeorgKycResultResponse.model_validate(data)
 
 
     def _ensure_configured(self) -> None:
         if not self._project_id or not self._machine_uid or not self._token or not self._process_info:
-            raise ApplicationException(status_code=500,message='Beorg service is not configured')
+            raise BeorgConfigException()

src/infrastructure/database/repositories/user_repository.py

@@ -4,7 +4,7 @@ from sqlalchemy import select
 from sqlalchemy.ext.asyncio import AsyncSession
 from src.application.abstractions.repositories import IUserRepository
 from src.application.domain.entities import UserEntity
-from src.application.domain.exceptions import ApplicationException
+from src.application.domain.exceptions import UserNotFoundException
 from src.infrastructure.database.models.user import UserModel
 
 
@@ -25,7 +25,7 @@ class UserRepository(IUserRepository):
         result = await self._session.execute(select(UserModel).where(UserModel.email == email))
         user = result.scalar_one_or_none()
         if user is None:
-            raise ApplicationException(status_code=404,message='User not found')
+            raise UserNotFoundException()
         return self._to_entity(user)
 
 
@@ -46,7 +46,7 @@ class UserRepository(IUserRepository):
     ) -> UserEntity:
         user = await self._session.get(UserModel,user_id)
         if user is None:
-            raise ApplicationException(status_code=404,message='User not found')
+            raise UserNotFoundException()
 
         user.first_name = first_name
         user.last_name = last_name

src/infrastructure/security/jwt.py

@@ -2,7 +2,7 @@ from __future__ import annotations
 from jose import jwt, ExpiredSignatureError, JWTError
 from src.application.contracts import ILogger, IJwtService
 from src.application.domain.dto import AccessTokenPayload
-from src.application.domain.exceptions import ApplicationException
+from src.application.domain.exceptions import ApplicationException,InvalidTokenException,JwtDecodeFailedException
 from src.infrastructure.config.settings import settings
 from src.infrastructure.vault import JwtKeyStore
 
@@ -17,7 +17,7 @@ class JwtService(IJwtService):
 
         if payload.get('type') != 'access':
             self._logger.warning(f'Access token invalid type received_type={payload.get("type")}')
-            raise ApplicationException(status_code=401, message='Invalid token type')
+            raise InvalidTokenException('Invalid token type')
 
         try:
             return AccessTokenPayload(
@@ -32,7 +32,7 @@ class JwtService(IJwtService):
             )
         except KeyError as exception:
             self._logger.warning(f'Access token missing claim error={str(exception)}')
-            raise ApplicationException(status_code=401, message=f'Missing token claim: {exception}')
+            raise InvalidTokenException(f'Missing token claim: {exception}')
 
     async def _decode_and_verify(self, token: str) -> dict:
         kid: str | None = None
@@ -42,12 +42,12 @@ class JwtService(IJwtService):
             kid = header.get('kid')
             if not kid:
                 self._logger.warning(f'JWT header missing kid header={header}')
-                raise ApplicationException(status_code=401, message='Missing token header: kid')
+                raise InvalidTokenException('Missing token header: kid')
 
             received_alg = header.get('alg')
             if received_alg != settings.JWT_ALGORITHM:
                 self._logger.warning(f'JWT invalid algorithm kid={kid} received_alg={received_alg} expected_alg={settings.JWT_ALGORITHM}')
-                raise ApplicationException(status_code=401, message='Invalid token algorithm')
+                raise InvalidTokenException('Invalid token algorithm')
 
             public_pem = await self._key_store.get_public_key_for_kid(str(kid))
 
@@ -58,7 +58,7 @@ class JwtService(IJwtService):
 
             if not public_pem:
                 self._logger.warning(f'JWT unknown kid kid={kid}')
-                raise ApplicationException(status_code=401, message='Unknown token kid')
+                raise InvalidTokenException('Unknown token kid')
 
             options = {
                 'verify_signature': True,
@@ -85,25 +85,25 @@ class JwtService(IJwtService):
 
             if 'sid' not in payload:
                 self._logger.warning(f'JWT missing sid claim kid={kid}')
-                raise ApplicationException(status_code=401, message='Missing token claim: sid')
+                raise InvalidTokenException('Missing token claim: sid')
 
             if 'type' not in payload:
                 self._logger.warning(f'JWT missing type claim kid={kid}')
-                raise ApplicationException(status_code=401, message='Missing token claim: type')
+                raise InvalidTokenException('Missing token claim: type')
 
             return payload
 
         except ExpiredSignatureError as exception:
             self._logger.info(f'JWT expired kid={kid} error={str(exception)}')
-            raise ApplicationException(status_code=401, message='Token expired')
+            raise InvalidTokenException('Token expired')
 
         except ApplicationException:
             raise
 
         except JWTError as exception:
             self._logger.warning(f'JWT decode failed kid={kid} error={str(exception)}')
-            raise ApplicationException(status_code=401, message='Invalid token')
+            raise InvalidTokenException()
 
         except Exception as exception:
             self._logger.error(f'Unexpected JWT decode error kid={kid} error={str(exception)}')
-            raise ApplicationException(status_code=500, message='JWT decode failed')
+            raise JwtDecodeFailedException()

src/main.py

@@ -3,13 +3,14 @@ from contextlib import asynccontextmanager
 import secrets
 from typing import AsyncGenerator
 from apscheduler.schedulers.asyncio import AsyncIOScheduler
-from fastapi import Depends, FastAPI, status
+from fastapi import Depends,FastAPI
+from fastapi.exceptions import RequestValidationError
 from fastapi.openapi.docs import get_redoc_html, get_swagger_ui_html
 from fastapi.responses import HTMLResponse
 from fastapi.security import HTTPBasic, HTTPBasicCredentials
 from src.application.commands import PollKycSessionsCommand
 from src.application.domain.enums import LogFormat,LogLevel
-from src.application.domain.exceptions import ApplicationException
+from src.application.domain.exceptions import ApplicationException,UnauthorizedException
 from src.infrastructure.beorg import BeorgService
 from src.infrastructure.config.settings import get_settings
 from src.infrastructure.database.context import async_session_maker
@@ -18,7 +19,7 @@ from src.infrastructure.vault import JwtKeyStore, start_jwt_keys_scheduler
 from src.infrastructure.utils import generate_instance_id
 from src.infrastructure.logger import logger
 from src.infrastructure.config import settings
-from src.presentation.handlers import application_exception_handler, unhandled_exception_handler
+from src.presentation.handlers import application_exception_handler,unhandled_exception_handler,validation_exception_handler
 from src.presentation.middleware import TraceIDMiddleware, SecurityHeadersMiddleware
 from src.presentation.routing import kyc_router
 
@@ -29,11 +30,9 @@ async def verify_credentials(credentials: HTTPBasicCredentials = Depends(securit
     user_ok = secrets.compare_digest(credentials.username, settings.DOCS_USERNAME)
     pass_ok = secrets.compare_digest(credentials.password, settings.DOCS_PASSWORD)
     if not (user_ok and pass_ok):
-        raise ApplicationException(
+        exception = UnauthorizedException()
-            status_code=status.HTTP_401_UNAUTHORIZED,
+        exception.headers = {'WWW-Authenticate': 'Basic'}
-            message='Unauthorized',
+        raise exception
-            headers={'WWW-Authenticate': 'Basic'},
-        )
     return credentials
 
 
@@ -97,6 +96,7 @@ app: FastAPI = FastAPI(
 )
 
 app.add_exception_handler(ApplicationException, application_exception_handler)
+app.add_exception_handler(RequestValidationError, validation_exception_handler)
 app.add_exception_handler(Exception, unhandled_exception_handler)
 
 app.include_router(kyc_router)

src/presentation/decorators/auth.py

@@ -1,7 +1,7 @@
 from fastapi import Depends, Request
 from fastapi.security.utils import get_authorization_scheme_param
 from src.application.contracts import IJwtService
-from src.application.domain.exceptions import ApplicationException
+from src.application.domain.exceptions import InvalidTokenException,NotAuthenticatedException
 from src.application.domain.dto import AccessTokenPayload, AuthContext
 from src.presentation.dependencies import get_jwt_service
 
@@ -27,10 +27,10 @@ async def require_access_token(
 ) -> AuthContext:
     token = _extract_access_token(request)
     if not token:
-        raise ApplicationException(status_code=401, message='Not authenticated')
+        raise NotAuthenticatedException()
 
     payload: AccessTokenPayload = await jwt_service.decode_access_token(token)
     if payload.type != 'access':
-        raise ApplicationException(status_code=401, message='Invalid token type')
+        raise InvalidTokenException('Invalid token type')
 
     return AuthContext(user_id=payload.sub, sid=payload.sid, token=payload)

src/presentation/decorators/csrf.py

@@ -3,7 +3,7 @@ import inspect
 from functools import wraps
 from typing import Callable, Awaitable, Any, Optional, Annotated
 from fastapi import Request, Header
-from src.application.domain.exceptions import ApplicationException
+from src.application.domain.exceptions import CsrfRequestRequiredException
 from src.infrastructure.security import CsrfService
 
 
@@ -39,10 +39,7 @@ def csrf_protect(
                         break
 
             if request is None:
-                raise ApplicationException(
+                raise CsrfRequestRequiredException()
-                    status_code=500,
-                    message='Request is required for CSRF protection',
-                )
 
             csrf = CsrfService()
 

src/presentation/handlers/__init__.py

@@ -1,4 +1,5 @@
 from fastapi import Request
+from fastapi.exceptions import RequestValidationError
 from fastapi.responses import ORJSONResponse
 from src.application.domain.exceptions import ApplicationException
 
@@ -6,13 +7,35 @@ from src.application.domain.exceptions import ApplicationException
 async def application_exception_handler(request: Request,exception: ApplicationException) -> ORJSONResponse:
     return ORJSONResponse(
         status_code=exception.status_code,
-        content={'detail': exception.message},
+        content={
+            'error': {
+                'code': exception.error_code,
+                'message': exception.message,
+            },
+        },
         headers=exception.headers,
     )
 
 
+async def validation_exception_handler(request: Request,exception: RequestValidationError) -> ORJSONResponse:
+    return ORJSONResponse(
+        status_code=422,
+        content={
+            'error': {
+                'code': 'request_validation_error',
+                'message': 'Request validation error',
+            },
+        },
+    )
+
+
 async def unhandled_exception_handler(request: Request,exception: Exception) -> ORJSONResponse:
     return ORJSONResponse(
         status_code=500,
-        content={'detail': 'Internal server error'},
+        content={
+            'error': {
+                'code': 'internal_server_error',
+                'message': 'Internal server error',
+            },
+        },
     )

src/presentation/routing/kyc.py

@@ -1,27 +1,81 @@
 from fastapi import APIRouter,Depends
-from fastapi.responses import ORJSONResponse
 from src.application.commands import GetKycSessionCommand,PassKycCommand
-from src.application.domain.dto import AuthContext
+from src.application.domain.dto import AuthContext,BeorgKycCreateResponse,KycSessionResponse
 from src.presentation.decorators.auth import require_access_token
 from src.presentation.dependencies.commands import get_kyc_session_command,get_pass_kyc_command
+from src.presentation.schemas import ErrorResponse
 
 
 kyc_router = APIRouter(prefix='/kyc', tags=['Kyc'])
 
+CREATE_KYC_RESPONSES = {
+    400: {
+        'model': ErrorResponse,
+        'description': 'Beorg rejected request. error.code: beorg_rejected',
+    },
+    401: {
+        'model': ErrorResponse,
+        'description': 'Authentication error. error.code: not_authenticated, invalid_token',
+    },
+    500: {
+        'model': ErrorResponse,
+        'description': 'Configuration or internal error. error.code: beorg_not_configured, internal_server_error',
+    },
+    502: {
+        'model': ErrorResponse,
+        'description': 'Beorg is unavailable. error.code: beorg_unavailable',
+    },
+    422: {
+        'model': ErrorResponse,
+        'description': 'Request validation error. error.code: request_validation_error',
+    },
+}
 
-@kyc_router.post('/create')
+GET_KYC_SESSION_RESPONSES = {
+    401: {
+        'model': ErrorResponse,
+        'description': 'Authentication error. error.code: not_authenticated, invalid_token',
+    },
+    404: {
+        'model': ErrorResponse,
+        'description': 'Active KYC session was not found. error.code: kyc_session_expired',
+    },
+    500: {
+        'model': ErrorResponse,
+        'description': 'Internal error. error.code: internal_server_error',
+    },
+    422: {
+        'model': ErrorResponse,
+        'description': 'Request validation error. error.code: request_validation_error',
+    },
+}
+
+
+@kyc_router.post(
+    '/create',
+    response_model=BeorgKycCreateResponse,
+    responses=CREATE_KYC_RESPONSES,
+    summary='Start KYC session',
+    description='Creates a Beorg KYC session for one hour and returns link, user token and QR code.',
+)
 async def create_kyc(
         #auth: AuthContext = Depends(require_access_token),
         command: PassKycCommand = Depends(get_pass_kyc_command),
-) -> ORJSONResponse:
+) -> BeorgKycCreateResponse:
     result = await command(user_id='01KPKAFN6J1NJBY15DX8JE2QYB')
-    return ORJSONResponse(result.model_dump())
+    return result
 
 
-@kyc_router.get('/session')
+@kyc_router.get(
+    '/session',
+    response_model=KycSessionResponse,
+    responses=GET_KYC_SESSION_RESPONSES,
+    summary='Get KYC session',
+    description='Returns latest KYC session status, link, QR code and expiration data.',
+)
 async def get_kyc_session(
         #auth: AuthContext = Depends(require_access_token),
         command: GetKycSessionCommand = Depends(get_kyc_session_command),
-) -> ORJSONResponse:
+) -> KycSessionResponse:
     result = await command(user_id='01KPKAFN6J1NJBY15DX8JE2QYB')
-    return ORJSONResponse(result.model_dump())
+    return result

src/presentation/schemas/__init__.py

@@ -0,0 +1 @@
+from src.presentation.schemas.error import ErrorDetail,ErrorResponse

src/presentation/schemas/error.py

@@ -0,0 +1,10 @@
+from pydantic import BaseModel
+
+
+class ErrorDetail(BaseModel):
+    code: str
+    message: str
+
+
+class ErrorResponse(BaseModel):
+    error: ErrorDetail