Source code for sqlalchemy_utils.types.uuid

import uuid

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

from ..compat import get_sqlalchemy_version
from .scalar_coercible import ScalarCoercible

sqlalchemy_version = get_sqlalchemy_version()

[docs]class UUIDType(ScalarCoercible, types.TypeDecorator): """ 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, default=uuid.uuid4 ) """ impl = types.BINARY(16) python_type = uuid.UUID cache_ok = True 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 __repr__(self): return util.generic_repr(self) def load_dialect_impl(self, dialect): if self.native and in ('postgresql', 'cockroachdb'): # Use the native UUID type. return dialect.type_descriptor(postgresql.UUID()) if == '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 # sqlalchemy >= 1.4.30 quotes UUID's automatically. # It is only necessary to quote UUID's in sqlalchemy < 1.4.30. if sqlalchemy_version < (1, 4, 30): def process_literal_param(self, value, dialect): return f"'{value}'" if value else value else: def process_literal_param(self, value, dialect): 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 in ( 'postgresql', 'mssql', 'cockroachdb' ): 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 in ( 'postgresql', 'mssql', 'cockroachdb' ): 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)