examples: add stop connection

bfxapi/examples/ws/start_stop_connection.py

@@ -0,0 +1,21 @@
+import os
+import sys
+sys.path.append('../../../')
+
+from bfxapi import Client
+
+bfx = Client(
+  logLevel='DEBUG',
+)
+
+@bfx.ws.on('order_book_snapshot')
+async def log_snapshot(data):
+  print ("Snapshot: {}".format(data))
+  # stop the websocket once a snapshot is received
+  await bfx.ws.stop()
+
+async def start():
+  await bfx.ws.subscribe('book', 'tBTCUSD')
+
+bfx.ws.on('connected', start)
+bfx.ws.run()