Add backoff timer for coingecko API

Set a future timestamp when we should retry getting coingecko data.

This fixes conversion from stake to fiat when running multiple bots
as we don't simply accept the 429 error from Coingecko but handle it.

freqtrade/rpc/fiat_convert.py

@@ -4,10 +4,12 @@ e.g BTC to USD
 """
 
 import logging
-from typing import Dict
+import datetime
 
+from typing import Dict
 from cachetools.ttl import TTLCache
 from pycoingecko import CoinGeckoAPI
+from requests.exceptions import RequestException
 
 from freqtrade.constants import SUPPORTED_FIAT
 
@@ -25,6 +27,7 @@ class CryptoToFiatConverter:
     _coingekko: CoinGeckoAPI = None
 
     _cryptomap: Dict = {}
+    _backoff = int
 
     def __new__(cls):
         """
@@ -47,8 +50,13 @@ class CryptoToFiatConverter:
     def _load_cryptomap(self) -> None:
         try:
             coinlistings = self._coingekko.get_coins_list()
-            # Create mapping table from synbol to coingekko_id
+            # Create mapping table from symbol to coingekko_id
             self._cryptomap = {x['symbol']: x['id'] for x in coinlistings}
+        except RequestException as request_exception:
+            if "429" in str(request_exception):
+                logger.warning("Too many requests for Coingecko API, backing off and trying again later.")
+                # Set backoff timestamp to 60 seconds in the future
+                self._backoff = datetime.datetime.now().timestamp() + 60
         except (Exception) as exception:
             logger.error(
                 f"Could not load FIAT Cryptocurrency map for the following problem: {exception}")
@@ -127,6 +135,9 @@ class CryptoToFiatConverter:
         if crypto_symbol == fiat_symbol:
             return 1.0
 
+        if self._cryptomap == {} and self._backoff <= datetime.datetime.now().timestamp():
+            self._load_cryptomap()
+
         if crypto_symbol not in self._cryptomap:
             # return 0 for unsupported stake currencies (fiat-convert should not break the bot)
             logger.warning("unsupported crypto-symbol %s - returning 0.0", crypto_symbol)