# testing/schema.py
# Copyright (C) 2005-2024 the SQLAlchemy authors and contributors
# <see AUTHORS file>
#
# This module is part of SQLAlchemy and is released under
# the MIT License: https://www.opensource.org/licenses/mit-license.php
import sys
from . import config
from . import exclusions
from .. import event
from .. import schema
from .. import types as sqltypes
from ..util import OrderedDict
__all__ = ["Table", "Column"]
table_options = {}
def Table(*args, **kw):
"""A schema.Table wrapper/hook for dialect-specific tweaks."""
test_opts = {k: kw.pop(k) for k in list(kw) if k.startswith("test_")}
kw.update(table_options)
if exclusions.against(config._current, "mysql"):
if (
"mysql_engine" not in kw
and "mysql_type" not in kw
and "autoload_with" not in kw
):
if "test_needs_fk" in test_opts or "test_needs_acid" in test_opts:
kw["mysql_engine"] = "InnoDB"
else:
kw["mysql_engine"] = "MyISAM"
elif exclusions.against(config._current, "mariadb"):
if (
"mariadb_engine" not in kw
and "mariadb_type" not in kw
and "autoload_with" not in kw
):
if "test_needs_fk" in test_opts or "test_needs_acid" in test_opts:
kw["mariadb_engine"] = "InnoDB"
else:
kw["mariadb_engine"] = "MyISAM"
# Apply some default cascading rules for self-referential foreign keys.
# MySQL InnoDB has some issues around selecting self-refs too.
if exclusions.against(config._current, "firebird"):
table_name = args[0]
unpack = config.db.dialect.identifier_preparer.unformat_identifiers
# Only going after ForeignKeys in Columns. May need to
# expand to ForeignKeyConstraint too.
fks = [
fk
for col in args
if isinstance(col, schema.Column)
for fk in col.foreign_keys
]
for fk in fks:
# root around in raw spec
ref = fk._colspec
if isinstance(ref, schema.Column):
name = ref.table.name
else:
# take just the table name: on FB there cannot be
# a schema, so the first element is always the
# table name, possibly followed by the field name
name = unpack(ref)[0]
if name == table_name:
if fk.ondelete is None:
fk.ondelete = "CASCADE"
if fk.onupdate is None:
fk.onupdate = "CASCADE"
return schema.Table(*args, **kw)
def Column(*args, **kw):
"""A schema.Column wrapper/hook for dialect-specific tweaks."""
test_opts = {k: kw.pop(k) for k in list(kw) if k.startswith("test_")}
if not config.requirements.foreign_key_ddl.enabled_for_config(config):
args = [arg for arg in args if not isinstance(arg, schema.ForeignKey)]
col = schema.Column(*args, **kw)
if test_opts.get("test_needs_autoincrement", False) and kw.get(
"primary_key", False
):
if col.default is None and col.server_default is None:
col.autoincrement = True
# allow any test suite to pick up on this
col.info["test_needs_autoincrement"] = True
# hardcoded rule for firebird, oracle; this should
# be moved out
if exclusions.against(config._current, "firebird", "oracle"):
def add_seq(c, tbl):
c._init_items(
schema.Sequence(
_truncate_name(
config.db.dialect, tbl.name + "_" + c.name + "_seq"
),
optional=True,
)
)
event.listen(col, "after_parent_attach", add_seq, propagate=True)
return col
class eq_type_affinity(object):
"""Helper to compare types inside of datastructures based on affinity.
E.g.::
eq_(
inspect(connection).get_columns("foo"),
[
{
"name": "id",
"type": testing.eq_type_affinity(sqltypes.INTEGER),
"nullable": False,
"default": None,
"autoincrement": False,
},
{
"name": "data",
"type": testing.eq_type_affinity(sqltypes.NullType),
"nullable": True,
"default": None,
"autoincrement": False,
},
],
)
"""
def __init__(self, target):
self.target = sqltypes.to_instance(target)
def __eq__(self, other):
return self.target._type_affinity is other._type_affinity
def __ne__(self, other):
return self.target._type_affinity is not other._type_affinity
class eq_clause_element(object):
"""Helper to compare SQL structures based on compare()"""
def __init__(self, target):
self.target = target
def __eq__(self, other):
return self.target.compare(other)
def __ne__(self, other):
return not self.target.compare(other)
def _truncate_name(dialect, name):
if len(name) > dialect.max_identifier_length:
return (
name[0 : max(dialect.max_identifier_length - 6, 0)]
+ "_"
+ hex(hash(name) % 64)[2:]
)
else:
return name
def pep435_enum(name):
# Implements PEP 435 in the minimal fashion needed by SQLAlchemy
__members__ = OrderedDict()
def __init__(self, name, value, alias=None):
self.name = name
self.value = value
self.__members__[name] = self
value_to_member[value] = self
setattr(self.__class__, name, self)
if alias:
self.__members__[alias] = self
setattr(self.__class__, alias, self)
value_to_member = {}
@classmethod
def get(cls, value):
return value_to_member[value]
someenum = type(
name,
(object,),
{"__members__": __members__, "__init__": __init__, "get": get},
)
# getframe() trick for pickling I don't understand courtesy
# Python namedtuple()
try:
module = sys._getframe(1).f_globals.get("__name__", "__main__")
except (AttributeError, ValueError):
pass
if module is not None:
someenum.__module__ = module
return someenum
