Merge pull request pymssql#267 from pymssql/pr210

PR pymssql#210 ready for merge.

Author: ramiro

pymssql.pyx

@@ -235,14 +235,16 @@ cdef class Connection:
                 raise InterfaceError('Connection is closed.')
             return self.conn
 
-    def __init__(self, conn, as_dict):
+    def __init__(self, conn, as_dict, autocommit):
         self.conn = conn
-        self._autocommit = False
+        self._autocommit = autocommit
         self.as_dict = as_dict
-        try:
-            self._conn.execute_non_query('BEGIN TRAN')
-        except Exception, e:
-            raise OperationalError('Cannot start transaction: ' + str(e.args[0]))
+
+        if not autocommit:
+            try:
+                self._conn.execute_non_query('BEGIN TRAN')
+            except Exception, e:
+                raise OperationalError('Cannot start transaction: ' + str(e.args[0]))
 
     def __dealloc__(self):
         if self.conn:
@@ -258,6 +260,7 @@ cdef class Connection:
 
         tran_type = 'ROLLBACK' if status else 'BEGIN'
         self._conn.execute_non_query('%s TRAN' % tran_type)
+
         self._autocommit = status
 
     def __enter__(self):
@@ -574,7 +577,7 @@ cdef class Cursor:
 
 def connect(server='.', user='', password='', database='', timeout=0,
         login_timeout=60, charset='UTF-8', as_dict=False,
-        host='', appname=None, port='1433', conn_properties=None):
+        host='', appname=None, port='1433', conn_properties=None, autocommit=False):
     """
     Constructor for creating a connection to the database. Returns a
     Connection object.
@@ -602,6 +605,8 @@ def connect(server='.', user='', password='', database='', timeout=0,
     :keyword conn_properties: SQL queries to send to the server upon connection
                               establishment. Can be a string or another kind
                               of iterable of strings
+    :keyword autocommit whether to use default autocommiting mode or not
+    :type autocommit: boolean
     """
 
     _mssql.login_timeout = login_timeout
@@ -637,7 +642,7 @@ def connect(server='.', user='', password='', database='', timeout=0,
     if timeout != 0:
         conn.query_timeout = timeout
 
-    return Connection(conn, as_dict)
+    return Connection(conn, as_dict, autocommit)
 
 def get_max_connections():
     """

tests/helpers.py

@@ -39,13 +39,14 @@ def mssqlconn(conn_properties=None):
     )
 
 
-def pymssqlconn():
+def pymssqlconn(**kwargs):
     return pymssql.connect(
         server=config.server,
         user=config.user,
         password=config.password,
         database=config.database,
         port=config.port,
+        **kwargs
     )
 
 

tests/test_pymssql.py

@@ -1,8 +1,11 @@
 import unittest
 
+import pytest
+
 import pymssql as pym
 
-from .helpers import pymssqlconn, PyTableBase, drop_table, CursorBase, eq_, config
+from .helpers import (pymssqlconn, PyTableBase, CursorBase, eq_, config,
+                      skip_test)
 
 class TestDBAPI2(object):
     def test_version(self):
@@ -83,13 +86,15 @@ def test_rollback_after_create_error(self):
         # too
         eq_(self.row_count(), 0)
 
+
 class TestCursor(CursorBase):
     dbmod = pym
 
     @classmethod
     def newconn(cls):
         cls.conn = pymssqlconn()
 
+
 class TestBasicConnection(unittest.TestCase):
 
     def connect(self, conn_props=None):
@@ -130,3 +135,82 @@ def test_conn_props_override(self):
             password=config.password
         )
         conn.close()
+
+
+class TestAutocommit(unittest.TestCase, PyTableBase):
+    tname = 'test'
+    cols = (
+        'name varchar(50)',
+    )
+
+    insert_query = 'INSERT INTO {tname} VALUES (%s)'.format(tname=tname)
+    select_query = 'SELECT * FROM {tname} WHERE name = (%s)'.format(tname=tname)
+
+    test_db_name = 'autocommit_test_database'
+
+    def setUp(self):
+        PyTableBase.setUp(self)
+
+    def tearDown(self):
+        self.conn._conn.execute_non_query("IF EXISTS(select * from sys.databases where name='{0}') DROP DATABASE {0}".format(self.test_db_name))
+
+    def test_db_creation_with_autocommit(self):
+        """
+        Try creating and dropping database with autocommit
+        """
+        cur = pymssqlconn(autocommit=True).cursor()
+        try:
+            cur.execute("CREATE DATABASE {0}".format(self.test_db_name))
+        except pym.OperationalError as e:
+            expected_msg = "CREATE DATABASE permission denied in database 'master'"
+            if expected_msg in str(e.args[1]):
+                skip_test('We have no CREATE DATABASE permission on test database')
+            else:
+                pytest.fail()
+        else:
+            cur.execute("DROP DATABASE {0}".format(self.test_db_name))
+
+    def test_db_creation_without_autocommit(self):
+        """
+        Try creating and dropping database without autocommit, expecting it to fail
+        """
+        cur = pymssqlconn(autocommit=False).cursor()
+        with pytest.raises(pym.OperationalError) as excinfo:
+            cur.execute("CREATE DATABASE autocommit_test_database")
+        expected_msg = "CREATE DATABASE statement not allowed within multi-statement transaction"
+        assert expected_msg in excinfo.exconly()
+
+    def test_autocommit_flipping_tf(self):
+        insert_value = 'true-false'
+        conn = pymssqlconn(autocommit=True)
+        conn.autocommit(False)
+        cur = conn.cursor()
+        cur.execute(self.insert_query, insert_value)
+        conn.commit()
+        cur.execute(self.select_query, insert_value)
+        row = cur.fetchone()
+        cur.close()
+        conn.close()
+        assert len(row) > 0
+
+    def test_autocommit_flipping_ft(self):
+        insert_value = 'false-true'
+        conn = pymssqlconn(autocommit=False)
+        conn.autocommit(True)
+        cur = conn.cursor()
+        cur.execute(self.insert_query, insert_value)
+        cur.execute(self.select_query, insert_value)
+        row = cur.fetchone()
+        assert len(row) > 0
+
+    def test_autocommit_false_does_not_commit(self):
+        insert_value = 'false'
+        conn = pymssqlconn(autocommit=False)
+        cur = conn.cursor()
+        cur.execute(self.insert_query, insert_value)
+        conn.rollback()
+        cur.execute(self.select_query, insert_value)
+        row = cur.fetchone()
+        cur.close()
+        conn.close()
+        assert row is None