add get_version method

Add a method to get the Jenkins server (or master) version

Signed-off-by: Antoine Musso <hashar@free.fr>
Change-Id: I9bbcf5fd1615246e53a9d83fec9d0c93c64b15aa

jenkins/__init__.py

@@ -330,6 +330,31 @@ class Jenkins(object):
             raise JenkinsException("Could not parse JSON info for server[%s]"
                                    % self.server)
 
+    def get_version(self):
+        """Get the version of this Master.
+
+        :returns: This master's version number ``str``
+
+        Example::
+
+            >>> j = Jenkins()
+            >>> info = j.get_version()
+            >>> print info
+            >>> 1.541
+
+        """
+        try:
+            request = Request(self.server)
+            request.add_header('X-Jenkins', '0.0')
+            response = urlopen(request)
+            return response.info().getheader('X-Jenkins')
+        except HTTPError:
+            raise JenkinsException("Error communicating with server[%s]"
+                                   % self.server)
+        except BadStatusLine:
+            raise JenkinsException("Error communicating with server[%s]"
+                                   % self.server)
+
     def get_jobs(self):
         """Get list of jobs running.
 

tests/test_jenkins.py

@@ -5,7 +5,7 @@ if sys.version_info < (2, 7):
 else:
     import unittest
 
-from mock import patch
+from mock import patch, Mock
 import six
 
 from tests.helper import jenkins
@@ -494,6 +494,41 @@ class JenkinsTest(unittest.TestCase):
             jenkins_mock.call_args[0][0].get_full_url(),
             u'http://example.com/job/TestJob/api/json?depth=0')
 
+    @patch('jenkins.urlopen')
+    def test_get_version__some_version(self, urlopen_mock):
+        j = jenkins.Jenkins('http://example.com/', 'test', 'test')
+
+        mock_response = Mock()
+        config = {'info.return_value.getheader.return_value': 'Version42'}
+        mock_response.configure_mock(**config)
+        urlopen_mock.side_effect = [mock_response]
+        self.assertEqual(j.get_version(), 'Version42')
+
+    @patch('jenkins.urlopen')
+    def test_get_version__HTTPError(self, urlopen_mock):
+        urlopen_mock.side_effect = jenkins.HTTPError(
+            'http://example.com/',
+            code=503,
+            msg="internal server error",
+            hdrs=[],
+            fp=None)
+        j = jenkins.Jenkins('http://example.com/', 'test', 'test')
+        with self.assertRaises(jenkins.JenkinsException) as context_manager:
+            j.get_version()
+        self.assertEqual(
+            str(context_manager.exception),
+            'Error communicating with server[http://example.com/]')
+
+    @patch('jenkins.urlopen')
+    def test_get_version__BadStatusLine(self, urlopen_mock):
+        urlopen_mock.side_effect = jenkins.BadStatusLine('not a valid status line')
+        j = jenkins.Jenkins('http://example.com/', 'test', 'test')
+        with self.assertRaises(jenkins.JenkinsException) as context_manager:
+            j.get_version()
+        self.assertEqual(
+            str(context_manager.exception),
+            'Error communicating with server[http://example.com/]')
+
     @patch.object(jenkins.Jenkins, 'jenkins_open')
     def test_get_jobs(self, jenkins_mock):
         jobs = {