Add EventNotSupported exception in errors.py.

bfxapi/websocket/BfxWebsocketClient.py

@@ -4,13 +4,19 @@ from pyee.asyncio import AsyncIOEventEmitter
 
 from .handlers import Channels, PublicChannelsHandler, AuthenticatedChannelsHandler
 
-from .errors import BfxWebsocketException, ConnectionNotOpen, InvalidAuthenticationCredentials, OutdatedClientVersion
+from .errors import BfxWebsocketException, ConnectionNotOpen, InvalidAuthenticationCredentials, EventNotSupported, OutdatedClientVersion
 
 HEARTBEAT = "hb"
 
 class BfxWebsocketClient(object):
     VERSION = 2
 
+    EVENTS = [
+        "open", "subscribed", "authenticated", "error",
+        *PublicChannelsHandler.EVENTS,
+        *AuthenticatedChannelsHandler.EVENTS
+    ]
+
     def __init__(self, host, API_KEY=None, API_SECRET=None):
         self.host, self.chanIds, self.event_emitter = host, dict(), AsyncIOEventEmitter()
 
@@ -102,12 +108,18 @@ class BfxWebsocketClient(object):
             await self.unsubscribe(chanId)
 
     def on(self, event):
+        if event not in BfxWebsocketClient.EVENTS:
+            raise EventNotSupported(f"Event <{event}> is not supported. To get a list of available events use BfxWebsocketClient.EVENTS.")
+
         def handler(function):
             self.event_emitter.on(event, function)
 
         return handler 
 
     def once(self, event):
+        if event not in BfxWebsocketClient.EVENTS:
+            raise EventNotSupported(f"Event <{event}> is not supported. To get a list of available events use BfxWebsocketClient.EVENTS.")
+
         def handler(function):
             self.event_emitter.once(event, function)
 

bfxapi/websocket/__init__.py

@@ -1,3 +1,3 @@
 from .BfxWebsocketClient import BfxWebsocketClient
 from .handlers import Channels
-from .errors import BfxWebsocketException, ConnectionNotOpen, InvalidAuthenticationCredentials, OutdatedClientVersion
+from .errors import BfxWebsocketException, ConnectionNotOpen, InvalidAuthenticationCredentials, EventNotSupported, OutdatedClientVersion

bfxapi/websocket/errors.py

@@ -25,6 +25,13 @@ class InvalidAuthenticationCredentials(BfxWebsocketException):
 
     pass
 
+class EventNotSupported(BfxWebsocketException):
+    """
+    This error indicates a failed attempt to subscribe to an event not supported by the BfxWebsocketClient.
+    """
+
+    pass
+
 class OutdatedClientVersion(BfxWebsocketException):
     """
     This error indicates a mismatch between the client version and the server WSS version.

bfxapi/websocket/handlers.py

@@ -21,6 +21,14 @@ class Channels(str, Enum):
     STATUS = "status"
 
 class PublicChannelsHandler(object):
+    EVENTS = [
+        "tp_ticker_update", "fc_ticker_update",
+        "tp_trade_executed", "tp_trade_execution_update", "fc_trade_executed", "fc_trade_execution_update", "tp_trades_snapshot", "fc_trades_snapshot",
+        "book_snapshot", "raw_book_snapshot", "book_update", "raw_book_update",
+        "candles_snapshot", "candles_update",
+        "derivatives_status_update"
+    ]
+
     def __init__(self, event_emitter):
         self.event_emitter = event_emitter
 
@@ -126,8 +134,19 @@ class PublicChannelsHandler(object):
                 subscription,
                 serializers.DerivativesStatus(*stream[0])
             )
-            
+
 class AuthenticatedChannelsHandler(object):
+    EVENTS = [
+        "order_snapshot", "new_order", "order_update", "order_cancel",
+        "position_snapshot", "new_position", "position_update", "position_close",
+        "trade_executed", "trade_execution_update",
+        "funding_offer_snapshot", "funding_offer_new", "funding_offer_update", "funding_offer_cancel",
+        "funding_credit_snapshot", "funding_credit_new", "funding_credit_update", "funding_credit_close",
+        "funding_loan_snapshot", "funding_loan_new", "funding_loan_update", "funding_loan_close",
+        "wallet_snapshot", "wallet_update",
+        "balance_update"
+    ]
+
     def __init__(self, event_emitter, strict = False):
         self.event_emitter, self.strict = event_emitter, strict
 

bfxapi/websocket/serializers.py

@@ -15,6 +15,8 @@ class _Serializer(object):
     def __call__(self, *values):
         return dict(self.__serialize(*values))
 
+#region Serializers definition for Websocket Public Channels
+
 TradingPairTicker = _Serializer("TradingPairTicker", labels=[
     "BID",
     "BID_SIZE",
@@ -121,4 +123,6 @@ DerivativesStatus = _Serializer("DerivativesStatus", labels=[
     "_PLACEHOLDER",
     "CLAMP_MIN",
     "CLAMP_MAX"
-])
+])
+
+#endregion