Merge remote-tracking branch 'afan/upstream-devel' into uw-0_5_0

1 files changed, 141 insertions, 0 deletions

diff --git a/python/rvi_ws.py b/python/rvi_ws.py
new file mode 100644
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+++ b/python/rvi_ws.py
@@ -0,0 +1,141 @@
+#
+# Copyright (C) 2016, Jaguar Land Rover
+#
+# This program is licensed under the terms and conditions of the
+# Mozilla Public License, version 2.0.  The full text of the 
+# Mozilla Public License is at https://www.mozilla.org/MPL/2.0/
+#
+# rvi_ws 0.1.0
+#  
+# This module is the websocket implementation of for RVI services. 
+
+# To use this code you will follow these steps.
+# 1. Import the rvi_ws class using "import rvi_ws"
+# 2. Instantiate a rvi_ws_client class object specifying the bundle_id, debug params, and host
+#     ex. 
+#         rvi_client = rvi_ws.rvi_ws_client(bundle_id = <string bundle name>, host = <string host url>, debug = <True|False>)
+# 3. Create a dictionary of services and their callback functions. The keys of the dictionary should be the string service name
+#    name and the value should be the pointer to the callback function.
+#    ex.
+#         def hello(...):
+#             ...
+#         def world(...):
+#             ...
+#
+#         rvi_client.register_services({"hello":hello, "world":world})
+#
+# 4. Register and run the services by invoking the services_run() function in the rvi_ws_client class. This will block all other code
+#    execution until the websocket connection closes in which case will return a None value.
+#    ex.
+#         rvi_client.services_run()
+#
+# Optionally there are a few more utility functions included in the rvi_ws_client class mainly setting properties of the class.
+#
+
+import websocket
+import json
+import threading
+
+try:
+    import thread
+# TODO use Threading instead of _thread in python3
+except ImportError:
+    import _thread as thread
+
+# rvi_ws_client will be in charge of handling all communication via websockets between the service bundle and RVI.
+
+class rvi_ws_client:
+
+    def __init__(self, bundle_id = None, debug = False, host = "ws://localhost:9008"):
+
+        self.DEBUG = debug
+        self.service_bundle_id = bundle_id
+        self.callback_funcs = {}
+        self.host = host
+
+    # set_ws_debug takes in parameter debug_status which is type bool. Will toggle on or off all websocket related debug messages.    
+    def set_ws_debug(self):
+
+        if self.DEBUG:
+            websocket.enableTrace(True)
+        else:
+            websocket.enableTrace(False)
+
+    # on_error will print an error if the websocket application encounters any and prints if debug is toggled on
+    def on_error(self,ws, error):
+        pass
+
+    # TODO unregister service for clean close of websocket, for time being will just print out debug
+    def on_close(self,ws):
+        pass
+    # What to do on the open of the application. Note we must register_services for this to do anything.
+    def on_open(self,ws):
+
+        def run(*args):
+
+            payload = {}
+            payload['json-rpc'] = "2.0"
+            payload['id'] = "0"
+            payload['method'] = "register_service"
+
+            for service_name, callback in self.callback_funcs.items():
+                payload['params'] = {"service_name":self.service_bundle_id+"/"+service_name}        
+                ws.send(json.dumps(payload))
+
+        opening = threading.Thread(target=run)
+        opening.start()
+
+    # on_message will route the message from the websocket to it's corresponding callback function that registered the service
+    def on_message(self,ws, message):
+
+        message_dict = json.loads(message)
+
+        try:
+            if (message_dict['method'] == 'message') and (message_dict['params']['service_name'][(2+len(self.service_bundle_id)):] in self.callback_funcs):
+                self.callback_funcs[message_dict['params']['service_name'][(2+len(self.service_bundle_id)):]](**message_dict['params']['parameters'])
+        except:
+            pass
+
+
+    # set_host will expect a string parameter that will change the class variable host which will connect to our websocket server
+    def set_host(self,target_host):
+
+        self.host = target_host
+        return True
+
+    # register_services will take in a dictionary of services to register. 
+    # The keys of the dictionary will be the service name and the value will be the callback function
+    # will return success on successfully changing the class' callback function dictionary
+    # Please make sure that the service name keys are strings.
+    # For example:
+    #     services = {
+    #         <service_name>:<callback function>,
+    #         <service_name>:<callback function>,
+    #         ....
+    #     }
+    def register_services(self,services):
+
+        self.callback_funcs = services
+        return True
+    # set_service_bundle expects a string parameter that will change the class variable service_bundle_id as the bundle_id tro register
+    def set_service_bundle(self, service_bundle):
+        self.service_bundle_id = service_bundle
+        return True
+
+    # services_run is a callable function for after everything is set to start the websocket client.
+    # Will block all remaining code until the websocket connection is broken. In which case will return None 
+    def services_run(self):
+
+        if self.service_bundle_id == None:
+            raise NameError('No Specified bundle_id')
+
+        self.set_ws_debug()
+
+        ws = websocket.WebSocketApp(self.host,
+                                    on_message = self.on_message,
+                                    on_error = self.on_error,
+                                    on_close = self.on_close)
+        ws.on_open = self.on_open
+
+        return ws.run_forever()
+