Add hierarchy logic to custom exceptions.

bfxapi/exceptions.py

@@ -0,0 +1,18 @@
+__all__ = [
+    "BfxBaseException",
+    "LabelerSerializerException"
+]
+
+class BfxBaseException(Exception):
+    """
+    Base class for every custom exception in bfxapi/rest/exceptions.py and bfxapi/websocket/exceptions.py.
+    """
+
+    pass
+
+class LabelerSerializerException(BfxBaseException):
+    """
+    This exception indicates an error thrown by the _Serializer class in bfxapi/labeler.py.
+    """
+
+    pass

bfxapi/labeler.py

@@ -1,3 +1,5 @@
+from .exceptions import LabelerSerializerException
+
 from typing import Generic, TypeVar, Iterable, Optional, List, Any
 
 T = TypeVar("T")
@@ -10,7 +12,7 @@ class _Serializer(Generic[T]):
         labels = list(filter(lambda label: label not in (skip or list()), self.__labels))
 
         if len(labels) > len(args):
-            raise Exception("<labels> and <*args> arguments should contain the same amount of elements.")
+            raise LabelerSerializerException("<labels> and <*args> arguments should contain the same amount of elements.")
 
         for index, label in enumerate(labels):
             if label not in self.__IGNORE:

bfxapi/rest/exceptions.py

@@ -1,12 +1,16 @@
+from ..exceptions import BfxBaseException
+
 __all__ = [
+    "BfxRestException",
+
     "RequestParametersError",
     "ResourceNotFound",
     "InvalidAuthenticationCredentials"
 ]
 
-class BfxRestException(Exception):
+class BfxRestException(BfxBaseException):
     """
-    Base class for all exceptions defined in bfxapi/rest/exceptions.py.
+    Base class for all custom exceptions in bfxapi/rest/exceptions.py.
     """
 
     pass