USERNAME_TOO_LONG: str = "error: username too long"
USERNAME_TOO_SHORT: str = "error: username too short"
USERNAME_MISSING: str = "error: username is missing"
PASSWORD_TOO_LONG: str = "error: password too long"
PASSWORD_TOO_SHORT: str = "error: password too short"
PASSWORD_MISSING: str = "error: password is missing"
USERNAME_ALREADY_USED: str = "error: username already used"

USER_ALREADY_LOGGED: str = "error: user already logged"
USER_INVALID: str = "error: username or password invalid"

USER_ADDED: str = "ok: user added"
USER_DELETED: str = "ok: account has been deleted"
USER_LOGGED: str = "ok: account valid"
USER_PASSWORD_UPDATED: str = "ok: password has been updated"
USER_LOGOUT: str = "ok: user logout"

METHOD_INVALID: str = "error: method invalid"