Fix TWS triggered trades msg packing

piker/brokers/ib.py

@@ -1442,14 +1442,14 @@ async def trades_dialogue(
             if getattr(msg, 'reqid', 0) < -1:
 
                 # it's a trade event generated by TWS usage.
-                log.warning(f"TWS triggered trade:\n{pformat(msg)}")
+                log.info(f"TWS triggered trade\n{pformat(msg.dict())}")
 
                 msg.reqid = 'tws-' + str(-1 * msg.reqid)
 
                 # mark msg as from "external system"
                 # TODO: probably something better then this.. and start
                 # considering multiplayer/group trades tracking
-                msg.external = True
+                msg.broker_details['external_src'] = 'tws'
                 continue
 
             # XXX: we always serialize to a dict for msgpack