Source code for sqlalchemy_utils.types.uuid

from __future__ import absolute_import

import uuid

from sqlalchemy import types
from sqlalchemy.dialects import mssql, postgresql

from .scalar_coercible import ScalarCoercible


[docs]class UUIDType(types.TypeDecorator, ScalarCoercible): """ Stores a UUID in the database natively when it can and falls back to a BINARY(16) or a CHAR(32) when it can't. :: from sqlalchemy_utils import UUIDType import uuid class User(Base): __tablename__ = 'user' # Pass `binary=False` to fallback to CHAR instead of BINARY id = sa.Column(UUIDType(binary=False), primary_key=True) """ impl = types.BINARY(16) python_type = uuid.UUID def __init__(self, binary=True, native=True): """ :param binary: Whether to use a BINARY(16) or CHAR(32) fallback. """ self.binary = binary self.native = native def load_dialect_impl(self, dialect): if dialect.name == 'postgresql' and self.native: # Use the native UUID type. return dialect.type_descriptor(postgresql.UUID()) if dialect.name == 'mssql' and self.native: # Use the native UNIQUEIDENTIFIER type. return dialect.type_descriptor(mssql.UNIQUEIDENTIFIER()) else: # Fallback to either a BINARY or a CHAR. kind = self.impl if self.binary else types.CHAR(32) return dialect.type_descriptor(kind) @staticmethod def _coerce(value): if value and not isinstance(value, uuid.UUID): try: value = uuid.UUID(value) except (TypeError, ValueError): value = uuid.UUID(bytes=value) return value def process_bind_param(self, value, dialect): if value is None: return value if not isinstance(value, uuid.UUID): value = self._coerce(value) if self.native and dialect.name in ('postgresql', 'mssql'): return str(value) return value.bytes if self.binary else value.hex def process_result_value(self, value, dialect): if value is None: return value if self.native and dialect.name in ('postgresql', 'mssql'): if isinstance(value, uuid.UUID): # Some drivers convert PostgreSQL's uuid values to # Python's uuid.UUID objects by themselves return value return uuid.UUID(value) return uuid.UUID(bytes=value) if self.binary else uuid.UUID(value)