- new oursql dialect added. [ticket:1613]

1 files changed, 217 insertions, 0 deletions

diff --git a/lib/sqlalchemy/dialects/mysql/oursql.py b/lib/sqlalchemy/dialects/mysql/oursql.py
new file mode 100644
index 000000000..4836e76a5
--- /dev/null
+++ b/lib/sqlalchemy/dialects/mysql/oursql.py
@@ -0,0 +1,217 @@
+"""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
+
+
+class _PlainQuery(unicode): 
+    pass
+
+
+class _oursqlNumeric(NUMERIC):
+    def result_processor(self, dialect):
+        if self.asdecimal:
+            return
+        def process(value):
+            if isinstance(value, decimal.Decimal):
+                return float(value)
+            else:
+                return value
+        return process
+
+
+class _oursqlBIT(BIT):
+    def result_processor(self, dialect):
+        """oursql already converts mysql bits, so."""
+        def process(value):
+            return value
+        return process
+
+
+class MySQL_oursql(MySQLDialect):
+    driver = 'oursql'
+    supports_unicode_statements = True
+    supports_unicode_binds = True
+    supports_sane_rowcount = True
+    supports_sane_multi_rowcount = True
+    
+    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)*."""
+        if isinstance(statement, _PlainQuery):
+            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):
+        connection.execute(_PlainQuery(query % connection.connection._escape_string(xid)))
+
+    # 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):
+        full_name = '.'.join(self.identifier_preparer._quote_free_identifiers(
+            schema, table_name))
+
+        st = "DESCRIBE %s" % full_name
+        rs = None
+        try:
+            try:
+                rs = connection.execute(_PlainQuery(st))
+                have = rs.rowcount > 0
+                rs.close()
+                return have
+            except exc.SQLError, e:
+                if self._extract_error_code(e) == 1146:
+                    return False
+                raise
+        finally:
+            if rs:
+                rs.close()
+
+    def _show_create_table(self, connection, table, charset=None,
+                           full_name=None):
+        """Run SHOW CREATE TABLE for a ``Table``."""
+
+        if full_name is None:
+            full_name = self.identifier_preparer.format_table(table)
+        st = "SHOW CREATE TABLE %s" % full_name
+
+        rp = None
+        try:
+            try:
+                rp = connection.execute(_PlainQuery(st))
+            except exc.SQLError, e:
+                if self._extract_error_code(e) == 1146:
+                    raise exc.NoSuchTableError(full_name)
+                else:
+                    raise
+            row = rp.fetchone()
+            if not row:
+                raise exc.NoSuchTableError(full_name)
+            return row[1].strip()
+        finally:
+            if rp:
+                rp.close()
+
+    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[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)
+        util.coerce_kw_type(opts, 'use_unicode', bool)
+
+        # FOUND_ROWS must be set in CLIENT_FLAGS to enable
+        # supports_sane_rowcount.
+        opts['found_rows'] = True
+        # And sqlalchemy assumes that you get an exception when mysql reports a warning.
+        opts['raise_on_warnings'] = 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."""
+        return connection.connection.charset
+    
+    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