"""Enhanced versions of schema.Table and schema.Column which establish
desired state for different backends.
"""
from sqlalchemy.test import testing
from sqlalchemy import schema
__all__ = 'Table', 'Column',
table_options = {}
def Table(*args, **kw):
"""A schema.Table wrapper/hook for dialect-specific tweaks."""
test_opts = dict([(k,kw.pop(k)) for k in kw.keys()
if k.startswith('test_')])
kw.update(table_options)
if testing.against('mysql'):
if 'mysql_engine' not in kw and 'mysql_type' not in kw:
if 'test_needs_fk' in test_opts or 'test_needs_acid' in test_opts:
kw['mysql_engine'] = 'InnoDB'
# Apply some default cascading rules for self-referential foreign keys.
# MySQL InnoDB has some issues around seleting self-refs too.
if testing.against('firebird'):
table_name = args[0]
unpack = (testing.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 = dict([(k,kw.pop(k)) for k in kw.keys()
if k.startswith('test_')])
col = schema.Column(*args, **kw)
if 'test_needs_autoincrement' in test_opts and \
kw.get('primary_key', False) and \
testing.against('firebird', 'oracle'):
def add_seq(tbl, c):
c._init_items(
schema.Sequence(_truncate_name(testing.db.dialect, tbl.name + '_' + c.name + '_seq'), optional=True)
)
col._on_table_attach(add_seq)
return col
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
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