Remove submodule, just put Dependencies in ./libs

libs/migrate/changeset/databases/sqlite.py

@@ -0,0 +1,155 @@
+"""
+   `SQLite`_ database specific implementations of changeset classes.
+
+   .. _`SQLite`: http://www.sqlite.org/
+"""
+from UserDict import DictMixin
+from copy import copy
+
+from sqlalchemy.databases import sqlite as sa_base
+
+from migrate import exceptions
+from migrate.changeset import ansisql, SQLA_06
+
+
+if not SQLA_06:
+    SQLiteSchemaGenerator = sa_base.SQLiteSchemaGenerator
+else:
+    SQLiteSchemaGenerator = sa_base.SQLiteDDLCompiler
+
+class SQLiteCommon(object):
+
+    def _not_supported(self, op):
+        raise exceptions.NotSupportedError("SQLite does not support "
+            "%s; see http://www.sqlite.org/lang_altertable.html" % op)
+
+
+class SQLiteHelper(SQLiteCommon):
+
+    def recreate_table(self,table,column=None,delta=None):
+        table_name = self.preparer.format_table(table)
+
+        # we remove all indexes so as not to have
+        # problems during copy and re-create
+        for index in table.indexes:
+            index.drop()
+
+        self.append('ALTER TABLE %s RENAME TO migration_tmp' % table_name)
+        self.execute()
+
+        insertion_string = self._modify_table(table, column, delta)
+
+        table.create()
+        self.append(insertion_string % {'table_name': table_name})
+        self.execute()
+        self.append('DROP TABLE migration_tmp')
+        self.execute()
+        
+    def visit_column(self, delta):
+        if isinstance(delta, DictMixin):
+            column = delta.result_column
+            table = self._to_table(delta.table)
+        else:
+            column = delta
+            table = self._to_table(column.table)
+        self.recreate_table(table,column,delta)
+
+class SQLiteColumnGenerator(SQLiteSchemaGenerator, 
+                            ansisql.ANSIColumnGenerator,
+                            # at the end so we get the normal
+                            # visit_column by default
+                            SQLiteHelper,
+                            SQLiteCommon
+                            ):
+    """SQLite ColumnGenerator"""
+
+    def _modify_table(self, table, column, delta):
+        columns = ' ,'.join(map(
+                self.preparer.format_column,
+                [c for c in table.columns if c.name!=column.name]))
+        return ('INSERT INTO %%(table_name)s (%(cols)s) '
+                'SELECT %(cols)s from migration_tmp')%{'cols':columns}
+
+    def visit_column(self,column):
+        if column.foreign_keys:
+            SQLiteHelper.visit_column(self,column)
+        else:
+            super(SQLiteColumnGenerator,self).visit_column(column)
+
+class SQLiteColumnDropper(SQLiteHelper, ansisql.ANSIColumnDropper):
+    """SQLite ColumnDropper"""
+
+    def _modify_table(self, table, column, delta):
+        
+        columns = ' ,'.join(map(self.preparer.format_column, table.columns))
+        return 'INSERT INTO %(table_name)s SELECT ' + columns + \
+            ' from migration_tmp'
+
+    def visit_column(self,column):
+        # For SQLite, we *have* to remove the column here so the table
+        # is re-created properly.
+        column.remove_from_table(column.table,unset_table=False)
+        super(SQLiteColumnDropper,self).visit_column(column)
+
+
+class SQLiteSchemaChanger(SQLiteHelper, ansisql.ANSISchemaChanger):
+    """SQLite SchemaChanger"""
+
+    def _modify_table(self, table, column, delta):
+        return 'INSERT INTO %(table_name)s SELECT * from migration_tmp'
+
+    def visit_index(self, index):
+        """Does not support ALTER INDEX"""
+        self._not_supported('ALTER INDEX')
+
+
+class SQLiteConstraintGenerator(ansisql.ANSIConstraintGenerator, SQLiteHelper, SQLiteCommon):
+
+    def visit_migrate_primary_key_constraint(self, constraint):
+        tmpl = "CREATE UNIQUE INDEX %s ON %s ( %s )"
+        cols = ', '.join(map(self.preparer.format_column, constraint.columns))
+        tname = self.preparer.format_table(constraint.table)
+        name = self.get_constraint_name(constraint)
+        msg = tmpl % (name, tname, cols)
+        self.append(msg)
+        self.execute()
+
+    def _modify_table(self, table, column, delta):
+        return 'INSERT INTO %(table_name)s SELECT * from migration_tmp'
+
+    def visit_migrate_foreign_key_constraint(self, *p, **k):
+        self.recreate_table(p[0].table)
+
+    def visit_migrate_unique_constraint(self, *p, **k):
+        self.recreate_table(p[0].table)
+
+
+class SQLiteConstraintDropper(ansisql.ANSIColumnDropper,
+                              SQLiteCommon,
+                              ansisql.ANSIConstraintCommon):
+
+    def visit_migrate_primary_key_constraint(self, constraint):
+        tmpl = "DROP INDEX %s "
+        name = self.get_constraint_name(constraint)
+        msg = tmpl % (name)
+        self.append(msg)
+        self.execute()
+
+    def visit_migrate_foreign_key_constraint(self, *p, **k):
+        self._not_supported('ALTER TABLE DROP CONSTRAINT')
+
+    def visit_migrate_check_constraint(self, *p, **k):
+        self._not_supported('ALTER TABLE DROP CONSTRAINT')
+
+    def visit_migrate_unique_constraint(self, *p, **k):
+        self._not_supported('ALTER TABLE DROP CONSTRAINT')
+
+
+# TODO: technically primary key is a NOT NULL + UNIQUE constraint, should add NOT NULL to index
+
+class SQLiteDialect(ansisql.ANSIDialect):
+    columngenerator = SQLiteColumnGenerator
+    columndropper = SQLiteColumnDropper
+    schemachanger = SQLiteSchemaChanger
+    constraintgenerator = SQLiteConstraintGenerator
+    constraintdropper = SQLiteConstraintDropper