Support an account field in clearing system

Each backend broker may support multiple (types) of accounts; this patch
lets clients send order requests that pass through an `account` field in
certain `emsd` <-> `brokerd` transactions. This allows each provider to read
in and conduct logic based on what account value is passed via requests
to the `trades_dialogue()` endpoint as well as tie together positioning
updates with relevant account keys for display in UIs.

This also adds relay support for a `Status` msg with a `'broker_errored'`
status which for now will trigger the same logic as cancelled orders on
the client side and thus will remove order lines submitted on a chart.

piker/clearing/_ems.py

@@ -201,6 +201,7 @@ async def clear_dark_triggers(
                         msg = BrokerdOrder(
                             action=cmd['action'],
                             oid=oid,
+                            account=cmd['account'],
                             time_ns=time.time_ns(),
 
                             # this **creates** new order request for the
@@ -621,8 +622,11 @@ async def translate_and_relay_brokerd_events(
             # another stupid ib error to handle
             # if 10147 in message: cancel
 
+            resp = 'broker_errored'
+            broker_details = msg.dict()
+
             # don't relay message to order requester client
-            continue
+            # continue
 
         elif name in (
             'status',
@@ -741,6 +745,7 @@ async def process_client_order_cmds(
                     oid=oid,
                     reqid=reqid,
                     time_ns=time.time_ns(),
+                    account=live_entry.account,
                 )
 
                 # NOTE: cancel response will be relayed back in messages
@@ -814,6 +819,7 @@ async def process_client_order_cmds(
                     action=action,
                     price=trigger_price,
                     size=size,
+                    account=msg.account,
                 )
 
                 # send request to backend
@@ -1016,6 +1022,7 @@ async def _emsd_main(
                 try:
                     _router.clients.add(ems_client_order_stream)
 
+                    # main entrypoint, run here until cancelled.
                     await process_client_order_cmds(
 
                         ems_client_order_stream,
@@ -1035,7 +1042,7 @@ async def _emsd_main(
 
                     dialogues = _router.dialogues
 
-                    for oid, client_stream in dialogues.items():
+                    for oid, client_stream in dialogues.copy().items():
 
                         if client_stream == ems_client_order_stream:
 

piker/ui/order_mode.py

@@ -103,7 +103,7 @@ class OrderMode:
     arrows: ArrowEditor
     multistatus: MultiStatus
     pp: PositionTracker
-    allocator: 'Allocator'  # noqa
+    alloc: 'Allocator'  # noqa
     pane: SettingsPane
 
     active: bool = False
@@ -193,6 +193,7 @@ class OrderMode:
         order = self._staged_order = Order(
             action=action,
             price=price,
+            account=self.alloc.account_name(),
             size=0,
             symbol=symbol,
             brokers=symbol.brokers,
@@ -538,6 +539,8 @@ async def open_order_mode(
 
         # load account names from ``brokers.toml``
         accounts = bidict(config.load_accounts())
+        # process pps back from broker, only present
+        # account names reported back from ``brokerd``.
         pp_account = None
 
         if pp_msg:
@@ -598,7 +601,7 @@ async def open_order_mode(
             arrows,
             multistatus,
             pp_tracker,
-            allocator=alloc,
+            alloc=alloc,
             pane=order_pane,
         )
 
@@ -823,10 +826,13 @@ async def process_trades_and_update_ui(
         elif resp in (
             'broker_cancelled',
             'broker_inactive',
+            'broker_errored',
             'dark_cancelled'
         ):
             # delete level line from view
             mode.on_cancel(oid)
+            broker_msg = msg['brokerd_msg']
+            log.warning(f'Order {oid} failed with:\n{pformat(broker_msg)}')
 
         elif resp in (
             'dark_triggered'