"""Support for the MySQL database via the oursql adapter. Character Sets -------------- oursql defaults to using ``utf8`` as the connection charset, but other encodings may be used instead. Like the MySQL-Python driver, unicode support can be completely disabled:: # oursql sets the connection charset to utf8 automatically; all strings come # back as utf8 str create_engine('mysql+oursql:///mydb?use_unicode=0') To not automatically use ``utf8`` and instead use whatever the connection defaults to, there is a separate parameter:: # use the default connection charset; all strings come back as unicode create_engine('mysql+oursql:///mydb?default_charset=1') # use latin1 as the connection charset; all strings come back as unicode create_engine('mysql+oursql:///mydb?charset=latin1') """ import decimal import re from sqlalchemy.dialects.mysql.base import (BIT, MySQLDialect, MySQLExecutionContext, MySQLCompiler, MySQLIdentifierPreparer, NUMERIC, _NumericType) from sqlalchemy.engine import base as engine_base, default from sqlalchemy.sql import operators as sql_operators from sqlalchemy import exc, log, schema, sql, types as sqltypes, util from sqlalchemy import processors class _oursqlNumeric(NUMERIC): def result_processor(self, dialect, coltype): if self.asdecimal: return None return processors.to_float class _oursqlBIT(BIT): def result_processor(self, dialect, coltype): """oursql already converts mysql bits, so.""" return None class MySQL_oursqlExecutionContext(MySQLExecutionContext): @property def plain_query(self): return self.execution_options.get('_oursql_plain_query', False) class MySQL_oursql(MySQLDialect): driver = 'oursql' # Py3K # description_encoding = None supports_unicode_statements = True supports_unicode_binds = True supports_sane_rowcount = True supports_sane_multi_rowcount = True execution_ctx_cls = MySQL_oursqlExecutionContext colspecs = util.update_copy( MySQLDialect.colspecs, { sqltypes.Time: sqltypes.Time, sqltypes.Numeric: _oursqlNumeric, BIT: _oursqlBIT, } ) @classmethod def dbapi(cls): return __import__('oursql') def do_execute(self, cursor, statement, parameters, context=None): """Provide an implementation of *cursor.execute(statement, parameters)*. # TODO: this isn't right. the supports_unicode_binds # and supports_unicode_statements flags should be used for this one. # also, don't call _detect_charset - use self._connection_charset # which is already configured (uses _detect_charset just once).""" # Py3K # if context is not None: # charset = self._detect_charset(context.connection) # if charset is not None: # statement = statement.encode(charset) # encoded_parameters = [] # for p in parameters: # if isinstance(p, str): # encoded_parameters.append(p.encode(charset)) # else: # encoded_parameters.append(p) # parameters = encoded_parameters if context and context.plain_query: cursor.execute(statement, plain_query=True) else: cursor.execute(statement, parameters) def do_begin(self, connection): connection.cursor().execute('BEGIN', plain_query=True) def _xa_query(self, connection, query, xid): # Py2K arg = connection.connection._escape_string(xid) # end Py2K # Py3K # charset = connection.connection.charset # arg = connection.connection._escape_string(xid.encode(charset)).decode(charset) connection.execution_options(_oursql_plain_query=True).execute(query % arg) # Because mysql is bad, these methods have to be reimplemented to use _PlainQuery. Basically, some queries # refuse to return any data if they're run through the parameterized query API, or refuse to be parameterized # in the first place. def do_begin_twophase(self, connection, xid): self._xa_query(connection, 'XA BEGIN "%s"', xid) def do_prepare_twophase(self, connection, xid): self._xa_query(connection, 'XA END "%s"', xid) self._xa_query(connection, 'XA PREPARE "%s"', xid) def do_rollback_twophase(self, connection, xid, is_prepared=True, recover=False): if not is_prepared: self._xa_query(connection, 'XA END "%s"', xid) self._xa_query(connection, 'XA ROLLBACK "%s"', xid) def do_commit_twophase(self, connection, xid, is_prepared=True, recover=False): if not is_prepared: self.do_prepare_twophase(connection, xid) self._xa_query(connection, 'XA COMMIT "%s"', xid) def has_table(self, connection, table_name, schema=None): return MySQLDialect.has_table(self, connection.execution_options(_oursql_plain_query=True), table_name, schema) # TODO: don't do this. just have base _show_create_table return # unicode. don't reuse _detect_charset(), use _connection_charset. def _show_create_table(self, connection, table, charset=None, full_name=None): sql = MySQLDialect._show_create_table(self, connection.contextual_connect(close_with_result=True).execution_options(_oursql_plain_query=True), table, charset, full_name) # Py3K # charset = self._detect_charset(connection) # if charset is not None: # sql = sql.decode(charset) return sql def is_disconnect(self, e): if isinstance(e, self.dbapi.ProgrammingError): # if underlying connection is closed, this is the error you get return e.errno is None and e.args[1].endswith('closed') else: return e.errno in (2006, 2013, 2014, 2045, 2055) def create_connect_args(self, url): opts = url.translate_connect_args(database='db', username='user', password='passwd') opts.update(url.query) util.coerce_kw_type(opts, 'port', int) util.coerce_kw_type(opts, 'compress', bool) util.coerce_kw_type(opts, 'autoping', bool) util.coerce_kw_type(opts, 'default_charset', bool) if opts.pop('default_charset', False): opts['charset'] = None else: util.coerce_kw_type(opts, 'charset', str) opts['use_unicode'] = opts.get('use_unicode', True) util.coerce_kw_type(opts, 'use_unicode', bool) # FOUND_ROWS must be set in CLIENT_FLAGS to enable # supports_sane_rowcount. opts.setdefault('found_rows', True) return [[], opts] def _get_server_version_info(self, connection): dbapi_con = connection.connection version = [] r = re.compile('[.\-]') for n in r.split(dbapi_con.server_info): try: version.append(int(n)) except ValueError: version.append(n) return tuple(version) def _extract_error_code(self, exception): try: return exception.orig.errno except AttributeError: return None def _detect_charset(self, connection): """Sniff out the character set in use for connection results.""" if hasattr(connection, 'connection'): if hasattr(connection.connection, 'use_unicode') and connection.connection.use_unicode: return None else: return connection.connection.charset else: return None def _compat_fetchall(self, rp, charset=None): """oursql isn't super-broken like MySQLdb, yaaay.""" return rp.fetchall() def _compat_fetchone(self, rp, charset=None): """oursql isn't super-broken like MySQLdb, yaaay.""" return rp.fetchone() dialect = MySQL_oursql