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another major code rafactor, reimplemented (almost from scratch)...
another major code rafactor, reimplemented (almost from scratch) the way caching works, Should be solid rock for now. Some code optymizations on scmModel.get() to make it don't load unneded things. Changed db cache to file that should also reduce memory size

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constraint.py
202 lines | 7.3 KiB | text/x-python | PythonLexer
"""
This module defines standalone schema constraint classes.
"""
from sqlalchemy import schema
from rhodecode.lib.dbmigrate.migrate.exceptions import *
from rhodecode.lib.dbmigrate.migrate.changeset import SQLA_06
class ConstraintChangeset(object):
"""Base class for Constraint classes."""
def _normalize_columns(self, cols, table_name=False):
"""Given: column objects or names; return col names and
(maybe) a table"""
colnames = []
table = None
for col in cols:
if isinstance(col, schema.Column):
if col.table is not None and table is None:
table = col.table
if table_name:
col = '.'.join((col.table.name, col.name))
else:
col = col.name
colnames.append(col)
return colnames, table
def __do_imports(self, visitor_name, *a, **kw):
engine = kw.pop('engine', self.table.bind)
from rhodecode.lib.dbmigrate.migrate.changeset.databases.visitor import (get_engine_visitor,
run_single_visitor)
visitorcallable = get_engine_visitor(engine, visitor_name)
run_single_visitor(engine, visitorcallable, self, *a, **kw)
def create(self, *a, **kw):
"""Create the constraint in the database.
:param engine: the database engine to use. If this is \
:keyword:`None` the instance's engine will be used
:type engine: :class:`sqlalchemy.engine.base.Engine`
:param connection: reuse connection istead of creating new one.
:type connection: :class:`sqlalchemy.engine.base.Connection` instance
"""
# TODO: set the parent here instead of in __init__
self.__do_imports('constraintgenerator', *a, **kw)
def drop(self, *a, **kw):
"""Drop the constraint from the database.
:param engine: the database engine to use. If this is
:keyword:`None` the instance's engine will be used
:param cascade: Issue CASCADE drop if database supports it
:type engine: :class:`sqlalchemy.engine.base.Engine`
:type cascade: bool
:param connection: reuse connection istead of creating new one.
:type connection: :class:`sqlalchemy.engine.base.Connection` instance
:returns: Instance with cleared columns
"""
self.cascade = kw.pop('cascade', False)
self.__do_imports('constraintdropper', *a, **kw)
# the spirit of Constraint objects is that they
# are immutable (just like in a DB. they're only ADDed
# or DROPped).
#self.columns.clear()
return self
class PrimaryKeyConstraint(ConstraintChangeset, schema.PrimaryKeyConstraint):
"""Construct PrimaryKeyConstraint
Migrate's additional parameters:
:param cols: Columns in constraint.
:param table: If columns are passed as strings, this kw is required
:type table: Table instance
:type cols: strings or Column instances
"""
__migrate_visit_name__ = 'migrate_primary_key_constraint'
def __init__(self, *cols, **kwargs):
colnames, table = self._normalize_columns(cols)
table = kwargs.pop('table', table)
super(PrimaryKeyConstraint, self).__init__(*colnames, **kwargs)
if table is not None:
self._set_parent(table)
def autoname(self):
"""Mimic the database's automatic constraint names"""
return "%s_pkey" % self.table.name
class ForeignKeyConstraint(ConstraintChangeset, schema.ForeignKeyConstraint):
"""Construct ForeignKeyConstraint
Migrate's additional parameters:
:param columns: Columns in constraint
:param refcolumns: Columns that this FK reffers to in another table.
:param table: If columns are passed as strings, this kw is required
:type table: Table instance
:type columns: list of strings or Column instances
:type refcolumns: list of strings or Column instances
"""
__migrate_visit_name__ = 'migrate_foreign_key_constraint'
def __init__(self, columns, refcolumns, *args, **kwargs):
colnames, table = self._normalize_columns(columns)
table = kwargs.pop('table', table)
refcolnames, reftable = self._normalize_columns(refcolumns,
table_name=True)
super(ForeignKeyConstraint, self).__init__(colnames, refcolnames, *args,
**kwargs)
if table is not None:
self._set_parent(table)
@property
def referenced(self):
return [e.column for e in self.elements]
@property
def reftable(self):
return self.referenced[0].table
def autoname(self):
"""Mimic the database's automatic constraint names"""
if hasattr(self.columns, 'keys'):
# SA <= 0.5
firstcol = self.columns[self.columns.keys()[0]]
ret = "%(table)s_%(firstcolumn)s_fkey" % dict(
table=firstcol.table.name,
firstcolumn=firstcol.name,)
else:
# SA >= 0.6
ret = "%(table)s_%(firstcolumn)s_fkey" % dict(
table=self.table.name,
firstcolumn=self.columns[0],)
return ret
class CheckConstraint(ConstraintChangeset, schema.CheckConstraint):
"""Construct CheckConstraint
Migrate's additional parameters:
:param sqltext: Plain SQL text to check condition
:param columns: If not name is applied, you must supply this kw\
to autoname constraint
:param table: If columns are passed as strings, this kw is required
:type table: Table instance
:type columns: list of Columns instances
:type sqltext: string
"""
__migrate_visit_name__ = 'migrate_check_constraint'
def __init__(self, sqltext, *args, **kwargs):
cols = kwargs.pop('columns', [])
if not cols and not kwargs.get('name', False):
raise InvalidConstraintError('You must either set "name"'
'parameter or "columns" to autogenarate it.')
colnames, table = self._normalize_columns(cols)
table = kwargs.pop('table', table)
schema.CheckConstraint.__init__(self, sqltext, *args, **kwargs)
if table is not None:
if not SQLA_06:
self.table = table
self._set_parent(table)
self.colnames = colnames
def autoname(self):
return "%(table)s_%(cols)s_check" % \
dict(table=self.table.name, cols="_".join(self.colnames))
class UniqueConstraint(ConstraintChangeset, schema.UniqueConstraint):
"""Construct UniqueConstraint
Migrate's additional parameters:
:param cols: Columns in constraint.
:param table: If columns are passed as strings, this kw is required
:type table: Table instance
:type cols: strings or Column instances
.. versionadded:: 0.6.0
"""
__migrate_visit_name__ = 'migrate_unique_constraint'
def __init__(self, *cols, **kwargs):
self.colnames, table = self._normalize_columns(cols)
table = kwargs.pop('table', table)
super(UniqueConstraint, self).__init__(*self.colnames, **kwargs)
if table is not None:
self._set_parent(table)
def autoname(self):
"""Mimic the database's automatic constraint names"""
return "%s_%s_key" % (self.table.name, self.colnames[0])