[dts] [PATCH] framework: support create addtional sessions on crb

[Yong Liu <yong.liu@intel.com>]

Add session create/destroy functions in crb module.
Suite can create addtional session in dut by this function.
When session useless, suite should close the session definitely.
Below is sample code addtional session:

    session = self.dut.new_session()
    session.send_expect("ls -al", "# ")
    self.dut.close_session(session=session)

Signed-off-by: Marvin Liu <yong.liu@intel.com>

diff --git a/framework/crb.py b/framework/crb.py
index 3c158ec..68fe399 100644
--- a/framework/crb.py
+++ b/framework/crb.py
@@ -56,6 +56,7 @@ class Crb(object):
         self.skip_setup = False
         self.serializer = serializer
         self.ports_info = None
+        self.sessions = []
 
         self.logger = getLogger(name)
         self.session = SSHConnection(self.get_ip_address(), name,
@@ -81,6 +82,24 @@ class Crb(object):
 
         return self.session.send_expect(cmds, expected, timeout, verify)
 
+    def create_session(self, name=""):
+        """
+        Create new session for addtional useage. This session will not enable log.
+        """
+        session = SSHConnection(self.get_ip_address(), name,
+                                     self.get_password())
+        self.sessions.append(session)
+        return session.session
+
+    def destroy_session(self, session=None):
+        """
+        Destroy addtional session.
+        """
+        for save_session in self.sessions:
+            if save_session.session == session:
+                save_session.close()
+            self.sessions.remove(save_session)
+
     def send_command(self, cmds, timeout=TIMEOUT, alt_session=False):
         """
         Send commands to crb and return string before timeout.
diff --git a/framework/dut.py b/framework/dut.py
index c75f325..2cea7fb 100644
--- a/framework/dut.py
+++ b/framework/dut.py
@@ -41,6 +41,7 @@ from crb import Crb
 from net_device import NetDevice
 from virt_resource import VirtResource
 from utils import RED
+from uuid import uuid4
 
 
 class Dut(Crb):
@@ -85,6 +86,21 @@ class Dut(Crb):
             self.host_session.init_log(self.logger)
             self.host_init_flag = True
 
+    def new_session(self):
+        """
+        Create new session for dut instance. Session name will be unique.
+        """
+        session_name = str(uuid4())
+        session = self.create_session(name=session_name)
+        session.send_expect("cd %s" % self.base_dir, "# ")
+        return session
+
+    def close_session(self, session):
+        """
+        close new session in dut instance
+        """
+        self.destroy_session(session)
+
     def change_config_option(self, target, parameter, value):
         """
         This function change option in the config file
-- 
1.9.3