cache_symbols refactor

piker/brokers/deribit/api.py

@@ -433,10 +433,38 @@ class Client:
 
     async def cache_symbols(
         self,
-    ) -> dict:
+        venue: MarketType = 'option',
 
-        if not self._pairs:
-            self._pairs = await self.symbol_info()
+    ) -> None:
+        # lookup internal mkt-specific pair table to update
+        pair_table: dict[str, Pair] = self._pairs
+
+        # make API request(s)
+        mkt_pairs = await self.symbol_info()
+
+        if not mkt_pairs:
+            raise SymbolNotFound(f'No market pairs found!?:\n{resp}')
+
+        pairs_view_subtable: dict[str, Pair] = {}
+
+        for instrument in mkt_pairs:
+            pair_type: Type = PAIRTYPES[venue]
+            try:
+                pair: Pair = pair_type(**mkt_pairs[instrument].to_dict())
+            except Exception as e:
+                e.add_note(
+                    "\nDon't panic, prolly stupid binance changed their symbology schema again..\n"
+                    'Check out their API docs here:\n\n'
+                    'https://binance-docs.github.io/apidocs/spot/en/#exchange-information'
+                )
+                raise
+            pair_table[pair.symbol.upper()] = pair
+
+            # update an additional top-level-cross-venue-table
+            # `._pairs: ChainMap` for search B0
+            pairs_view_subtable[pair.bs_fqme] = pair
+
+        self._pairs.maps.append(pairs_view_subtable)
 
         return self._pairs