Add option pairlist parameter type

freqtrade/plugins/pairlist/IPairList.py

@@ -31,6 +31,12 @@ class __StringPairlistParameter(__PairlistParameterBase):
     default: Union[str, None]
 
 
+class __OptionPairlistParameter(__PairlistParameterBase):
+    type: Literal["option"]
+    default: Union[str, None]
+    options: List[str]
+
+
 class __BoolPairlistParameter(__PairlistParameterBase):
     type: Literal["boolean"]
     default: Union[bool, None]
@@ -39,6 +45,7 @@ class __BoolPairlistParameter(__PairlistParameterBase):
 PairlistParameter = Union[
     __NumberPairlistParameter,
     __StringPairlistParameter,
+    __OptionPairlistParameter,
     __BoolPairlistParameter
     ]
 

freqtrade/plugins/pairlist/ShuffleFilter.py

@@ -59,8 +59,9 @@ class ShuffleFilter(IPairList):
     def available_parameters() -> Dict[str, PairlistParameter]:
         return {
             "shuffle_frequency": {
-                "type": "string",
+                "type": "option",
                 "default": "candle",
+                "options": ["candle", "iteration"],
                 "description": "Shuffle frequency",
                 "help": "Shuffle frequency. Can be either 'candle' or 'iteration'.",
             },

freqtrade/plugins/pairlist/VolumePairList.py

@@ -123,8 +123,9 @@ class VolumePairList(IPairList):
                 "help": "Number of assets to use from the pairlist",
             },
             "sort_key": {
-                "type": "string",
+                "type": "option",
                 "default": "quoteVolume",
+                "options": SORT_VALUES,
                 "description": "Sort key",
                 "help": "Sort key to use for sorting the pairlist.",
             },