Merge pull request pymssql#197 from pymssql/variant-azure

Support SQL Azure

Author: msabramo

ChangeLog

@@ -1,6 +1,22 @@
 Change Log
 ==========
 
+Version 2.x.y - To be released
+==============================
+
+Features
+--------
+
+- Compatibility with Azure
+
+  It is now possible to transparently connect to `SQL Server instances`_
+  accessible as part of the Azure_ cloud services.
+
+  .. note:: If you need to connect to Azure make sure you use FreeTDS 0.91 or newer.
+
+.. _SQL Server instances: http://www.windowsazure.com/en-us/services/sql-database/
+.. _Azure: https://www.windowsazure.com/
+
 Version 2.1.0 - 2014-02-25 - `Marc Abramowitz <http://marc-abramowitz.com/>`_
 =============================================================================
 

_mssql.pyx

@@ -66,6 +66,9 @@ from cpython.tuple cimport PyTuple_New, PyTuple_SetItem
 cdef extern from "pymssql_version.h":
     const char *PYMSSQL_VERSION
 
+cdef extern from "cpp_helpers.h":
+    cdef bint FREETDS_SUPPORTS_DBSETLDBNAME
+
 # Vars to store messages from the server in
 cdef int _mssql_last_msg_no = 0
 cdef int _mssql_last_msg_severity = 0
@@ -578,6 +581,18 @@ cdef class MSSQLConnection:
             strncpy(self._charset, _charset, PYMSSQL_CHARSETBUFSIZE)
             DBSETLCHARSET(login, self._charset)
 
+        # For Python 3, we need to convert unicode to byte strings
+        cdef bytes dbname_bytes
+        cdef char *dbname_cstr
+        # Put the DB name in the login LOGINREC because it helps with connections to Azure
+        if database:
+            if FREETDS_SUPPORTS_DBSETLDBNAME:
+                dbname_bytes = database.encode('ascii')
+                dbname_cstr = dbname_bytes
+                DBSETLDBNAME(login, dbname_cstr)
+            else:
+                log("_mssql.MSSQLConnection.__init__(): Warning: This version of FreeTDS doesn't support selecting the DB name when setting up the connection. This will keep connections to Azure from working.")
+
         # Set the login timeout
         dbsetlogintime(login_timeout)
 

cpp_helpers.h

@@ -0,0 +1,40 @@
+/*
+
+ cpp_helpers.h
+
+   Copyright (C) 2014 pymssql development team.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ MA  02110-1301  USA
+*/
+
+/*
+
+ Helper module to aid with the fact that Cython doesn't support C pre-procesor
+ macros yet. See:
+
+  https://groups.google.com/forum/#!topic/cython-users/HASNraxsGGw
+  https://github.com/denik/cython-ifdef
+  http://grokbase.com/t/gg/cython-users/128rn1399p/equivalent-of-ifdef-preprocessor
+
+*/
+
+#include "sybdb.h"
+
+#ifdef DBSETLDBNAME
+#define FREETDS_SUPPORTS_DBSETLDBNAME 1
+#else
+#define FREETDS_SUPPORTS_DBSETLDBNAME 0
+#endif

docs/freetds.rst

@@ -2,8 +2,6 @@
 FreeTDS configuration
 =====================
 
-Basic info on setting up connections with FreeTDS.
-
 pymssql uses FreeTDS package to connect to SQL Server instances. You have to
 tell it how to find your database servers. The most basic info is host name,
 port number, and protocol version to use.

docs/ref/_mssql.rst

@@ -88,6 +88,8 @@ Functions
         SET QUOTED_IDENTIFIER ON;
         SET TEXTSIZE 2147483647; -- http://msdn.microsoft.com/en-us/library/aa259190%28v=sql.80%29.aspx
 
+    .. note:: If you need to connect to Azure make sure you use FreeTDS 0.91 or newer.
+
 ``MSSQLConnection`` object properties
 -------------------------------------
 

docs/ref/pymssql.rst

@@ -54,6 +54,8 @@ Functions
     :keyword port: the TCP port to use to connect to the server
     :type port: string
 
+  .. note:: If you need to connect to Azure make sure you use FreeTDS 0.91 or newer.
+
 .. function:: get_dbversion()
 
    TBD

pymssql.pyx

@@ -572,7 +572,7 @@ def connect(server='.', user='', password='', database='', timeout=0,
     :keyword appname: Set the application name to use for the connection
     :type appname: string
     :keyword port: the TCP port to use to connect to the server
-    :type appname: string
+    :type port: string
     """
 
     _mssql.login_timeout = login_timeout

sqlfront.pxd

@@ -651,5 +651,6 @@ cdef extern from "sqlfront.h":
     RETCODE DBSETLUSER(LOGINREC *x, char *y)
     RETCODE DBSETLCHARSET(LOGINREC *x, char *y)
     RETCODE DBSETLVERSION(LOGINREC *login, BYTE version)
+    RETCODE DBSETLDBNAME(LOGINREC *x, char *y)
 
 ctypedef int LINE_T

tests/test_config.py

@@ -37,20 +37,14 @@ def test_config_values(self):
             database = 'tempdb',
             )
         assert b'user_name = bob' in config_dump
-        # it would be nice if this was the DB name, see test_dbsetldbname()
-        assert b'database = \n' in config_dump
+        assert b'database = tempdb\n' in config_dump
         # test default port
         assert b'port = 1433' in config_dump
         # not sure why 7.1 version is used instead of 8.0 which is the
         # default
         assert b'major_version = 7' in config_dump
         assert b'minor_version = 1' in config_dump
 
-    def test_dbsetldbname(self):
-        # sybdb.h defines DBSETLDBNAME, we should try to use that to get
-        # the DB in the config dump for debugging purposes
-        skip_test() # test_dbsetldbname
-
     def test_tds_protocol_version_42(self):
         config_dump = self.connect(
             server='dontnameyourserverthis',