|
- # testing/schema.py
- # Copyright (C) 2005-2021 the SQLAlchemy authors and contributors
- # <see AUTHORS file>
- #
- # This module is part of SQLAlchemy and is released under
- # the MIT License: http://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
|