parametrize outdated_offset to simplify sandbox usage

freqtrade/constants.py

@@ -145,7 +145,8 @@ CONF_SCHEMA = {
                         'pattern': '^[0-9A-Z]+/[0-9A-Z]+$'
                     },
                     'uniqueItems': True
-                }
+                },
+                'outdated_offset': {'type': 'integer', 'minimum': 1}
             },
             'required': ['name', 'key', 'secret', 'pair_whitelist']
         }

freqtrade/strategy/interface.py

@@ -155,7 +155,8 @@ class IStrategy(ABC):
         # Check if dataframe is out of date
         signal_date = arrow.get(latest['date'])
         interval_minutes = constants.TICKER_INTERVAL_MINUTES[interval]
-        if signal_date < (arrow.utcnow().shift(minutes=-(interval_minutes * 2 + 5))):
+        offset = self.config.get('outdated_offset', 5)
+        if signal_date < (arrow.utcnow().shift(minutes=-(interval_minutes * 2 + offset))):
             logger.warning(
                 'Outdated history for pair %s. Last tick is %s minutes old',
                 pair,