sql.py 文件源码

def run(self, engine, step=None):
        """Runs SQL script through raw dbapi execute call"""
        text = self.source()
        # Don't rely on SA's autocommit here
        # (SA uses .startswith to check if a commit is needed. What if script
        # starts with a comment?)
        conn = engine.connect()
        try:
            trans = conn.begin()
            try:
                # ignore transaction management statements that are
                # redundant in SQL script context and result in
                # operational error being returned.
                #
                # Note: we don't ignore ROLLBACK in migration scripts
                # since its usage would be insane anyway, and we're
                # better to fail on its occurance instead of ignoring it
                # (and committing transaction, which is contradictory to
                # the whole idea of ROLLBACK)
                ignored_statements = ('BEGIN', 'END', 'COMMIT')
                ignored_regex = re.compile('^\s*(%s).*;?$' % '|'.join(ignored_statements),
                                           re.IGNORECASE)

                # NOTE(ihrachys): script may contain multiple statements, and
                # not all drivers reliably handle multistatement queries or
                # commands passed to .execute(), so split them and execute one
                # by one
                text = sqlparse.format(text, strip_comments=True, strip_whitespace=True)
                for statement in sqlparse.split(text):
                    if statement:
                        if re.match(ignored_regex, statement):
                            log.warning('"%s" found in SQL script; ignoring' % statement)
                        else:
                            conn.execute(statement)
                trans.commit()
            except Exception as e:
                log.error("SQL script %s failed: %s", self.path, e)
                trans.rollback()
                raise
        finally:
            conn.close()