From 13ff09f42164d31c6a8621791d7b687e0cbba7d2 Mon Sep 17 00:00:00 2001
From: "Srivats P." <pstavirs@gmail.com>
Date: Wed, 4 Jun 2014 07:35:43 +0530
Subject: [PATCH] CLI: Added BLOB RPC support to python binding; updated the
 binding example to use the RPC; added a convenience method -
 saveCaptureBuffer() to DroneProxy

---
 binding/core.py    | 11 +++++++++++
 binding/example.py | 31 +++++++++++++++++++++++++++++--
 binding/rpc.py     | 18 ++++++++++++++++--
 3 files changed, 56 insertions(+), 4 deletions(-)

diff --git a/binding/core.py b/binding/core.py
index a25d965..994d236 100644
--- a/binding/core.py
+++ b/binding/core.py
@@ -15,6 +15,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>
 
+import os
 from rpc import OstinatoRpcChannel, OstinatoRpcController
 import protocols.protocol_pb2 as ost_pb
 
@@ -40,9 +41,19 @@ class DroneProxy(object):
     def connect(self):
         self.channel.connect(self.host, self.port)
 
+    def disconnect(self):
+        self.channel.disconnect()
+
     def callRpcMethod(self, method_name, request):
         controller = OstinatoRpcController()
         ost_pb.OstService_Stub.__dict__[method_name](
                     self.stub, controller, request, None)
         return controller.response
 
+    def saveCaptureBuffer(self, buffer, file_name):
+         f= open(file_name, 'wb')
+         f.write(buffer)
+         f.flush()
+         os.fsync(f.fileno())
+         f.close()
+
diff --git a/binding/example.py b/binding/example.py
index 54d13ef..2150222 100644
--- a/binding/example.py
+++ b/binding/example.py
@@ -1,7 +1,10 @@
+#! /usr/bin/env python
+
 # standard modules
+import logging
+import os
 import sys
 import time
-import logging
 
 # ostinato modules - prepend 'ostinato.' to the module names when using
 # an installed package i.e ostinato.core and ostinato.protocols.xxx
@@ -88,7 +91,10 @@ try:
     drone.clearStats(tx_port)
     drone.clearStats(rx_port)
 
-    # start transmit
+    # start capture and transmit
+    log.info('starting capture')
+    drone.startCapture(rx_port)
+    time.sleep(1)
     log.info('starting transmit')
     drone.startTx(tx_port)
 
@@ -96,6 +102,12 @@ try:
     log.info('waiting for transmit to finish ...')
     time.sleep(7)
 
+    # stop transmit and capture
+    log.info('stopping transmit')
+    drone.stopTx(tx_port)
+    log.info('stopping capture')
+    drone.stopCapture(rx_port)
+
     # get tx/rx stats
     log.info('retreiving stats')
     tx_stats = drone.getStats(tx_port)
@@ -106,6 +118,21 @@ try:
     log.info('tx pkts = %d, rx pkts = %d' % 
             (tx_stats.port_stats[0].tx_pkts, rx_stats.port_stats[0].rx_pkts))
 
+    # retrieve and dump received packets
+    log.info('getting Rx capture buffer')
+    buff = drone.getCaptureBuffer(rx_port.port_id[0])
+    drone.saveCaptureBuffer(buff, 'capture.pcap')
+    log.info('dumping Rx capture buffer')
+    os.system('tshark -r capture.pcap')
+    os.remove('capture.pcap')
+
+    # delete streams
+    log.info('deleting tx_stream %d' % stream_id.stream_id[0].id)
+    drone.deleteStream(stream_id)
+
+    # bye for now
+    drone.disconnect()
+
 except Exception, ex:
     log.exception(ex)
     sys.exit(1)
diff --git a/binding/rpc.py b/binding/rpc.py
index 6da362f..1d68ad2 100644
--- a/binding/rpc.py
+++ b/binding/rpc.py
@@ -31,13 +31,20 @@ class OstinatoRpcChannel(RpcChannel):
     def connect(self, host, port):
         self.sock.connect((host, port))
 
+    def disconnect(self):
+        self.sock.close()
+
     def CallMethod(self, method, controller, request, response_class, done):
         OST_PB_MSG_HDR_SIZE = 8
         OST_PB_MSG_TYPE_REQUEST = 1
+        OST_PB_MSG_TYPE_RESPONSE = 2
+        OST_PB_MSG_TYPE_BLOB = 3
+
         req = request.SerializeToString()
         self.sock.sendall(struct.pack('>HHI', 
             OST_PB_MSG_TYPE_REQUEST, method.index, len(req)) + req)
 
+        # receive and parse header
         hdr = ''
         while len(hdr) < OST_PB_MSG_HDR_SIZE:
             chunk = self.sock.recv(OST_PB_MSG_HDR_SIZE - len(hdr))
@@ -47,6 +54,7 @@ class OstinatoRpcChannel(RpcChannel):
 
         (type, method, resp_len) = struct.unpack('>HHI', hdr)
 
+        # receive and parse the actual response message
         resp = ''
         while len(resp) < resp_len:
             chunk = self.sock.recv(resp_len - len(resp))
@@ -54,8 +62,14 @@ class OstinatoRpcChannel(RpcChannel):
                 raise RuntimeError("socket connection broken")
             resp = resp + chunk
 
-        response = response_class()
-        response.ParseFromString(resp)
+        if type == OST_PB_MSG_TYPE_RESPONSE:
+            response = response_class()
+            response.ParseFromString(resp)
+        elif type == OST_PB_MSG_TYPE_BLOB:
+            response = resp
+        else:
+            print 'unsupported msg type %d received in respone to %s' % \
+                    type, method.name
 
         controller.response = response