update prosys example client for events

examples/client_to_prosys_events.py

+import sys
+sys.path.insert(0, "..")
+import logging
+
+from opcua import Client
+from opcua import ua
+from IPython import embed
+
+
+class SubHandler(object):
+
+    """
+    Subscription Handler. To receive events from server for a subscription
+    """
+
+    def datachange_notification(self, node, val, data):
+        print("Python: New data change event", node, val)
+
+    def event_notification(self, event):
+        print("Python: New event", event.EventType)
+
+
+
+
+if __name__ == "__main__":
+    #from IPython import embed
+    logging.basicConfig(level=logging.WARN)
+    client = Client("opc.tcp://localhost:53530/OPCUA/SimulationServer/")
+    #client = Client("opc.tcp://olivier:olivierpass@localhost:53530/OPCUA/SimulationServer/")
+    try:
+        client.connect()
+        root = client.get_root_node()
+        print("Root is", root)
+
+        handler = SubHandler()
+        sub = client.create_subscription(500, handler)
+        handle = sub.subscribe_events(evtype=2788)
+        # refresh server condition to force generation of events
+        cond = root.get_child(["0:Types", "0:EventTypes", "0:BaseEventType", "0:ConditionType"])
+        cond.call_method("0:ConditionRefresh", ua.Variant(sub.subscription_id, ua.VariantType.UInt32))
+
+        embed()
+    finally:
+        client.disconnect()