papi: add a per-call _timeout option

add the ability to override the default timeout value on a per-call
 basis.
 Use:
   rv = self.vapi.papi.cli_inband(cmd='wait 10', _timeout=15)

Type: feature

Change-Id: Ia90a58586a1f63e02118599a2a4b7141e5a0b90d
Signed-off-by: Paul Vinciguerra <pvinci@vinciconsulting.com>

test/test_cli.py

@@ -17,7 +17,7 @@ class TestCLI(VppTestCase):
     @classmethod
     def setUpClass(cls):
         # using the framework default
-        # cls.vapi_response_timeout = 5
+        cls.vapi_response_timeout = 5
         super(TestCLI, cls).setUpClass()
 
     @classmethod
@@ -44,6 +44,11 @@ class TestCLI(VppTestCase):
                 vpp_transport_shmem.VppTransportShmemIOError) as ctx:
             rv = self.vapi.papi.cli_inband(cmd='wait 10')
 
+    def test_long_cli_delay_override(self):
+        """ Test per-command _timeout option."""  # noqa
+        rv = self.vapi.papi.cli_inband(cmd='wait 10', _timeout=15)
+        self.assertEqual(rv.retval, 0)
+
 
 class TestCLIExtendedVapiTimeout(VppTestCase):
     maxDiff = None