[Yardstick-233]latency measurment by using pktgen-dpdk

VM A runs pktgen-dpdk as a traffic generator and is connected
back-to-back with VM B running testpmd for forwarding packets.

1. use linux expect to fetch the latency statics data.
2. fetch 10 samples of latency and calculate avg_latency.
3. use screen to keep test scripts running in the background.
4. add a function send_command() for screen in ssh.py

JIRA:YARDSTICK-233

Change-Id: I90ae64b3d198c79f159275ae35715eb284f05080
Signed-off-by: wu.zhihui <wu.zhihui1@zte.com.cn>

1 files changed, 9 insertions, 0 deletions

diff --git a/tests/unit/test_ssh.py b/tests/unit/test_ssh.py
index 4260b39bc..574da0343 100644
--- a/tests/unit/test_ssh.py
+++ b/tests/unit/test_ssh.py
@@ -156,6 +156,15 @@ class SSHTestCase(unittest.TestCase):
         self.assertEqual([mock.call("uname")] * 3,
                          self.test_client.execute.mock_calls)
 
+    @mock.patch("yardstick.ssh.paramiko")
+    def test_send_command(self, mock_paramiko):
+        paramiko_sshclient = self.test_client._get_client()
+        with mock.patch.object(paramiko_sshclient, "exec_command") \
+            as mock_paramiko_exec_command:
+            self.test_client.send_command('cmd')
+        mock_paramiko_exec_command.assert_called_once_with('cmd',
+                                                            get_pty=True)
+
 
 class SSHRunTestCase(unittest.TestCase):
     """Test SSH.run method in different aspects.