108 lines
3.3 KiB
Python
108 lines
3.3 KiB
Python
"""
|
|
`SQLite`_ database specific implementations of changeset classes.
|
|
|
|
.. _`SQLite`: http://www.sqlite.org/
|
|
"""
|
|
from migrate.changeset import ansisql, constraint, exceptions
|
|
from sqlalchemy.databases import sqlite as sa_base
|
|
from sqlalchemy import Table, MetaData
|
|
#import sqlalchemy as sa
|
|
|
|
SQLiteSchemaGenerator = sa_base.SQLiteSchemaGenerator
|
|
|
|
|
|
class SQLiteHelper(object):
|
|
|
|
def visit_column(self, param):
|
|
try:
|
|
table = self._to_table(param.table)
|
|
except:
|
|
table = self._to_table(param)
|
|
raise
|
|
table_name = self._to_table_name(table)
|
|
self.append('ALTER TABLE %s RENAME TO migration_tmp' % table_name)
|
|
self.execute()
|
|
|
|
insertion_string = self._modify_table(table, param)
|
|
|
|
table.create()
|
|
self.append(insertion_string % {'table_name': table_name})
|
|
self.execute()
|
|
self.append('DROP TABLE migration_tmp')
|
|
self.execute()
|
|
|
|
|
|
class SQLiteColumnGenerator(SQLiteSchemaGenerator,
|
|
ansisql.ANSIColumnGenerator):
|
|
pass
|
|
|
|
|
|
class SQLiteColumnDropper(SQLiteHelper, ansisql.ANSIColumnDropper):
|
|
|
|
def _modify_table(self, table, column):
|
|
del table.columns[column.name]
|
|
columns = ','.join([c.name for c in table.columns])
|
|
return 'INSERT INTO %(table_name)s SELECT ' + columns + \
|
|
' from migration_tmp'
|
|
|
|
|
|
class SQLiteSchemaChanger(SQLiteHelper, ansisql.ANSISchemaChanger):
|
|
|
|
def _not_supported(self, op):
|
|
raise exceptions.NotSupportedError("SQLite does not support "
|
|
"%s; see http://www.sqlite.org/lang_altertable.html"%op)
|
|
|
|
def _modify_table(self, table, delta):
|
|
column = table.columns[delta.current_name]
|
|
for k, v in delta.items():
|
|
setattr(column, k, v)
|
|
return 'INSERT INTO %(table_name)s SELECT * from migration_tmp'
|
|
|
|
def visit_index(self, param):
|
|
self._not_supported('ALTER INDEX')
|
|
|
|
def _do_quote_column_identifier(self, identifier):
|
|
return '"%s"'%identifier
|
|
|
|
|
|
class SQLiteConstraintGenerator(ansisql.ANSIConstraintGenerator):
|
|
|
|
def visit_migrate_primary_key_constraint(self, constraint):
|
|
tmpl = "CREATE UNIQUE INDEX %s ON %s ( %s )"
|
|
cols = ','.join([c.name for c in constraint.columns])
|
|
tname = constraint.table.name
|
|
name = constraint.name
|
|
msg = tmpl % (name, tname, cols)
|
|
self.append(msg)
|
|
self.execute()
|
|
|
|
|
|
class SQLiteFKGenerator(SQLiteSchemaChanger, ansisql.ANSIFKGenerator):
|
|
def visit_column(self, column):
|
|
"""Create foreign keys for a column (table already exists); #32"""
|
|
|
|
if self.fk:
|
|
self._not_supported("ALTER TABLE ADD FOREIGN KEY")
|
|
|
|
if self.buffer.getvalue() !='':
|
|
self.execute()
|
|
|
|
|
|
class SQLiteConstraintDropper(ansisql.ANSIColumnDropper):
|
|
|
|
def visit_migrate_primary_key_constraint(self, constraint):
|
|
tmpl = "DROP INDEX %s "
|
|
name = constraint.name
|
|
msg = tmpl % (name)
|
|
self.append(msg)
|
|
self.execute()
|
|
|
|
|
|
class SQLiteDialect(ansisql.ANSIDialect):
|
|
columngenerator = SQLiteColumnGenerator
|
|
columndropper = SQLiteColumnDropper
|
|
schemachanger = SQLiteSchemaChanger
|
|
constraintgenerator = SQLiteConstraintGenerator
|
|
constraintdropper = SQLiteConstraintDropper
|
|
columnfkgenerator = SQLiteFKGenerator
|