ipmitool drivers fail with integer passwords

ironic.drivers.modules.ipmitool gives "Failed to create the password file.
expected a character buffer object" WARNING message and it causes "Error:
IPMI call failed: power status..". "expected a character buffer object" is
a python error message and raised when write() function expected string as
input type  but gets something else (i.e. int / numeric) if ipmi password
is set just using numbers(i.e 12345678)

This simple bug fix solves the issue by casting "password" to string.

Change-Id: Id9645e06eb707ef21a7cb99c420309f54a95aa9b
Closes-Bug: 1416298

ironic/drivers/modules/ipmitool.py

@@ -187,7 +187,7 @@ def _make_password_file(password):
         fd, path = tempfile.mkstemp()
         os.fchmod(fd, stat.S_IRUSR | stat.S_IWUSR)
         with os.fdopen(fd, "w") as f:
-            f.write(password)
+            f.write(str(password))
 
         yield path
         utils.delete_if_exists(path)

ironic/tests/drivers/test_ipmitool.py

@@ -16,6 +16,7 @@
 #    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 #    License for the specific language governing permissions and limitations
 #    under the License.
+#
 
 """Test class for IPMITool driver module."""
 
@@ -221,16 +222,22 @@ class IPMIToolPrivateMethodTestCase(db_base.DbTestCase):
                 driver_info=INFO_DICT)
         self.info = ipmi._parse_driver_info(self.node)
 
-    def test__make_password_file(self, mock_sleep):
-        with ipmi._make_password_file(self.info.get('password')) as pw_file:
+    def _test__make_password_file(self, mock_sleep, input_password):
+        with ipmi._make_password_file(input_password) as pw_file:
             del_chk_pw_file = pw_file
             self.assertTrue(os.path.isfile(pw_file))
             self.assertEqual(0o600, os.stat(pw_file)[stat.ST_MODE] & 0o777)
             with open(pw_file, "r") as f:
                 password = f.read()
-            self.assertEqual(self.info.get('password'), password)
+            self.assertEqual(str(input_password), password)
         self.assertFalse(os.path.isfile(del_chk_pw_file))
 
+    def test__make_password_file_str_password(self, mock_sleep):
+        self._test__make_password_file(mock_sleep, self.info.get('password'))
+
+    def test__make_password_file_with_numeric_password(self, mock_sleep):
+        self._test__make_password_file(mock_sleep, 12345)
+
     def test__parse_driver_info(self, mock_sleep):
         # make sure we get back the expected things
         _OPTIONS = ['address', 'username', 'password', 'uuid']