FastAPI Validation

FastAPI Validation support both SQLAlchemy for sql database and BeanieODM for nosql Database. To use the @Exists and @Unique decorator we need to set global-variable for the database_type Check the sample code below

For SQL Database using SQLAlchemy as ORM

from fastapi_validation import DatabaseTypeEnum

engine = create_engine(SQLALCHEMY_DATABASE_URL, echo=False, pool_size=50, max_overflow=100)
global_db_session: Session = sessionmaker(
    autoflush=False, autobegin=True, bind=engine, join_transaction_mode='rollback_only'
)()
def run_with_global_session(callback):
    try:
        return callback(global_db_session)
    except Exception as e:
        global_db_session.rollback()
        raise e

GlobalVariable.set('run_with_global_session', run_with_global_session)
GlobalVariable.set('database_type', DatabaseTypeEnum.SQL)

For Nosql Database using Beanie as ODM

GlobalVariable.set('database_type', DatabaseTypeEnum.NOSQL) # We can skip this line because the defautl database_type is No-SQL

How to use

Exists decorator

from fastapi_validation import FieldValidator, Exists

class UpdateProfileDto(BaseDto):
  avatar_id: UUID | None = None

  _exist_avatar = FieldValidator('avatar_id')(
    Exists(
      table=MediaEntity,
      column='id',
      customs=[{'column': 'type', 'value': MediaType.IMAGE}],
    )
  )

Unique decorator

class InviteUserDto(BaseDto):
  username: str = Field(max_length=255, min_length=1)

  _unique_username = FieldValidator('username')(
    Unique(table=UserEntity, column='username', customs=[{'column': 'deleted_at', 'value': None}])
  )

Customized FieldValidator handler

from fastapi_validation import FieldValidator

class InviteUserDto(BaseDto):
  username: str = Field(max_length=255, min_length=1)

  _validate_username = FieldValidator('username')(validate_username)

def validate_username(username: str | None = None) -> str:
  if not username:
    return username

  if not re.search(USERNAME_REGEX, username):
    raise ValueError('invalid username')

  return username

ModelValidator

from fastapi_validation import ModelValidator

def required_phone_number_and_code_pair(cls, values):
  phone_code, phone_number = values.phone_code, values.phone_number

  is_missing_only_phone_number = phone_code is not None and phone_number is None
  is_missing_only_phone_code = phone_number is not None and phone_code is None

  if is_missing_only_phone_number or is_missing_only_phone_code:
    throw_validation_with_exception(MissingPhoneNumberPhoneCodeError(loc=('body', 'phone_code', 'phone_number')))

  return values

class CheckPhoneTokenDto(BaseDto):
  phone_code: CodeValidation
  phone_number: PhoneNumberValidation
  token: int = Field(ge=100000, le=999999)

  _phone_number_and_code_validation = ModelValidator()(required_phone_number_and_code_pair)

list_int_enum_query_param

from fastapi_validation import SortParam, Sorts, 
from fastapi_validation import list_int_enum_query_param

class RoleEnum(int, Enum):
  ADMIN = 1
  ADMIN_ASSISTANT = 2

@controller('users')
@tag('Users')
@auth()
class UserController:
  def __init__(
    self, user_service: UserService = Depends()
  ):
    self.user_service = user_service

  @get()
  @response(UserResponse)
  async def list_users_by_role(
    self,
    roles: list[int] = list_int_enum_query_param(values=RoleEnum, key='roles'),
  ):
    return await self.user_service.list_users_by_role(roles)

PasswordValidation

from fastapi_validation import PasswordValidation

class ChangePasswordDto(BaseDto):
  old_password: PasswordValidation
  new_password: PasswordValidation