Apply fixes and refactoring to the bfxapi.handlers sub-package.

bfxapi/websocket/exceptions.py

@@ -58,4 +58,11 @@ class InvalidAuthenticationCredentials(BfxWebsocketException):
     This error indicates that the user has provided incorrect credentials (API-KEY and API-SECRET) for authentication.
     """
 
+    pass
+
+class HandlerNotFound(BfxWebsocketException):
+    """
+    This error indicates that a handler was not found for an incoming message.
+    """
+
     pass

bfxapi/websocket/handlers/authenticated_channels_handler.py

@@ -1,10 +1,8 @@
-from typing import List
-
-from ..types import *
-
 from .. import serializers
 
-from ..exceptions import BfxWebsocketException
+from .. types import *
+
+from .. exceptions import HandlerNotFound
 
 class AuthenticatedChannelsHandler(object):
     __abbreviations = {
@@ -37,7 +35,7 @@ class AuthenticatedChannelsHandler(object):
         *list(__abbreviations.values()) 
     ]
 
-    def __init__(self, event_emitter, strict = False):
+    def __init__(self, event_emitter, strict = True):
         self.event_emitter, self.strict = event_emitter, strict
 
     def handle(self, type, stream):
@@ -52,20 +50,20 @@ class AuthenticatedChannelsHandler(object):
                     return self.event_emitter.emit(event, [ serializer.parse(*substream) for substream in stream ])
 
                 return self.event_emitter.emit(event, serializer.parse(*stream))
-        
-        if self.strict == True:
-            raise BfxWebsocketException(f"Event of type <{type}> not found in self.__handlers.")
+
+        if self.strict:
+            raise HandlerNotFound(f"No handler found for event of type <{type}>.")
     
     def __notification(self, stream):
         type, serializer = "notification", serializers._Notification(serializer=None)
 
         if stream[1] == "on-req" or stream[1] == "ou-req" or stream[1] == "oc-req":
-            type, serializer = f"{stream[1]}-notification", serializers._Notification[Order](serializer=serializers.Order)
+            type, serializer = f"{stream[1]}-notification", serializers._Notification(serializer=serializers.Order)
 
         if stream[1] == "oc_multi-req":
-            type, serializer = f"{stream[1]}-notification", serializers._Notification[List[Order]](serializer=serializers.Order, iterate=True)
+            type, serializer = f"{stream[1]}-notification", serializers._Notification(serializer=serializers.Order, iterate=True)
 
         if stream[1] == "fon-req" or stream[1] == "foc-req":
-            type, serializer = f"{stream[1]}-notification", serializers._Notification[FundingOffer](serializer=serializers.FundingOffer)
+            type, serializer = f"{stream[1]}-notification", serializers._Notification(serializer=serializers.FundingOffer)
 
         return self.event_emitter.emit(type, serializer.parse(*stream))

bfxapi/websocket/handlers/public_channels_handler.py

@@ -1,8 +1,8 @@
-from ..types import *
-
 from .. import serializers
 
-from ..enums import Channels
+from .. types import *
+
+from .. exceptions import HandlerNotFound
 
 class PublicChannelsHandler(object):
     EVENTS = [
@@ -13,23 +13,26 @@ class PublicChannelsHandler(object):
         "derivatives_status_update",
     ]
 
-    def __init__(self, event_emitter):
-        self.event_emitter = event_emitter
+    def __init__(self, event_emitter, strict = True):
+        self.event_emitter, self.strict = event_emitter, strict
 
         self.__handlers = {
-            Channels.TICKER: self.__ticker_channel_handler,
-            Channels.TRADES: self.__trades_channel_handler,
-            Channels.BOOK: self.__book_channel_handler,
-            Channels.CANDLES: self.__candles_channel_handler,
-            Channels.STATUS: self.__status_channel_handler
+            "ticker": self.__ticker_channel_handler,
+            "trades": self.__trades_channel_handler,
+            "book": self.__book_channel_handler,
+            "candles": self.__candles_channel_handler,
+            "status": self.__status_channel_handler
         }
 
     def handle(self, subscription, *stream):
         _clear = lambda dictionary, *args: { key: value for key, value in dictionary.items() if key not in args }
 
-        if channel := subscription["channel"] or channel in self.__handlers.keys():
+        if (channel := subscription["channel"]) and channel in self.__handlers.keys():
             return self.__handlers[channel](_clear(subscription, "event", "channel", "subId"), *stream)
 
+        if self.strict:
+            raise HandlerNotFound(f"No handler found for channel <{subscription['channel']}>.")
+
     def __ticker_channel_handler(self, subscription, *stream):
         if subscription["symbol"].startswith("t"):
             return self.event_emitter.emit(
@@ -46,7 +49,7 @@ class PublicChannelsHandler(object):
             )
 
     def __trades_channel_handler(self, subscription, *stream):
-        if type := stream[0] or type in [ "te", "tu", "fte", "ftu" ]:
+        if (type := stream[0]) and type in [ "te", "tu", "fte", "ftu" ]:
             if subscription["symbol"].startswith("t"):
                 return self.event_emitter.emit(
                     { "te": "t_trade_executed", "tu": "t_trade_execution_update" }[type],