Move get_buy_rate to exchange class

freqtrade/exchange/exchange.py

@@ -22,8 +22,8 @@ from pandas import DataFrame
 from freqtrade.constants import DEFAULT_AMOUNT_RESERVE_PERCENT, ListPairsWithTimeframes
 from freqtrade.data.converter import ohlcv_to_dataframe, trades_dict_to_list
 from freqtrade.exceptions import (DDosProtection, ExchangeError, InsufficientFundsError,
-                                  InvalidOrderException, OperationalException, RetryableOrderError,
+                                  InvalidOrderException, OperationalException, PricingError,
-                                  TemporaryError)
+                                  RetryableOrderError, TemporaryError)
 from freqtrade.exchange.common import (API_FETCH_ORDER_RETRY_COUNT, BAD_EXCHANGES,
                                        EXCHANGE_HAS_OPTIONAL, EXCHANGE_HAS_REQUIRED, retrier,
                                        retrier_async)
@@ -88,6 +88,7 @@ class Exchange:
 
         # Cache for 10 minutes ...
         self._fetch_tickers_cache: TTLCache = TTLCache(maxsize=1, ttl=60 * 10)
+        self._buy_rate_cache: TTLCache = TTLCache(maxsize=100, ttl=1800)
 
         # Holds candles
         self._klines: Dict[Tuple[str, str], DataFrame] = {}
@@ -911,6 +912,52 @@ class Exchange:
         except ccxt.BaseError as e:
             raise OperationalException(e) from e
 
+    def get_buy_rate(self, pair: str, refresh: bool) -> float:
+        """
+        Calculates bid target between current ask price and last price
+        :param pair: Pair to get rate for
+        :param refresh: allow cached data
+        :return: float: Price
+        :raises PricingError if orderbook price could not be determined.
+        """
+        if not refresh:
+            rate = self._buy_rate_cache.get(pair)
+            # Check if cache has been invalidated
+            if rate:
+                logger.debug(f"Using cached buy rate for {pair}.")
+                return rate
+
+        bid_strategy = self._config.get('bid_strategy', {})
+        if 'use_order_book' in bid_strategy and bid_strategy.get('use_order_book', False):
+
+            order_book_top = bid_strategy.get('order_book_top', 1)
+            order_book = self.fetch_l2_order_book(pair, order_book_top)
+            logger.debug('order_book %s', order_book)
+            # top 1 = index 0
+            try:
+                rate_from_l2 = order_book[f"{bid_strategy['price_side']}s"][order_book_top - 1][0]
+            except (IndexError, KeyError) as e:
+                logger.warning(
+                    "Buy Price from orderbook could not be determined."
+                    f"Orderbook: {order_book}"
+                 )
+                raise PricingError from e
+            logger.info(f"Buy price from orderbook {bid_strategy['price_side'].capitalize()} side "
+                        f"- top {order_book_top} order book buy rate {rate_from_l2:.8f}")
+            used_rate = rate_from_l2
+        else:
+            logger.info(f"Using Last {bid_strategy['price_side'].capitalize()} / Last Price")
+            ticker = self.fetch_ticker(pair)
+            ticker_rate = ticker[bid_strategy['price_side']]
+            if ticker['last'] and ticker_rate > ticker['last']:
+                balance = bid_strategy['ask_last_balance']
+                ticker_rate = ticker_rate + balance * (ticker['last'] - ticker_rate)
+            used_rate = ticker_rate
+
+        self._buy_rate_cache[pair] = used_rate
+
+        return used_rate
+
     # Fee handling
 
     @retrier

freqtrade/freqtradebot.py

@@ -62,7 +62,6 @@ class FreqtradeBot(LoggingMixin):
         # Caching only applies to RPC methods, so prices for open trades are still
         # refreshed once every iteration.
         self._sell_rate_cache: TTLCache = TTLCache(maxsize=100, ttl=1800)
-        self._buy_rate_cache: TTLCache = TTLCache(maxsize=100, ttl=1800)
 
         self.strategy: IStrategy = StrategyResolver.load_strategy(self.config)
 
@@ -396,50 +395,6 @@ class FreqtradeBot(LoggingMixin):
 
         return trades_created
 
-    def get_buy_rate(self, pair: str, refresh: bool) -> float:
-        """
-        Calculates bid target between current ask price and last price
-        :param pair: Pair to get rate for
-        :param refresh: allow cached data
-        :return: float: Price
-        """
-        if not refresh:
-            rate = self._buy_rate_cache.get(pair)
-            # Check if cache has been invalidated
-            if rate:
-                logger.debug(f"Using cached buy rate for {pair}.")
-                return rate
-
-        bid_strategy = self.config.get('bid_strategy', {})
-        if 'use_order_book' in bid_strategy and bid_strategy.get('use_order_book', False):
-
-            order_book_top = bid_strategy.get('order_book_top', 1)
-            order_book = self.exchange.fetch_l2_order_book(pair, order_book_top)
-            logger.debug('order_book %s', order_book)
-            # top 1 = index 0
-            try:
-                rate_from_l2 = order_book[f"{bid_strategy['price_side']}s"][order_book_top - 1][0]
-            except (IndexError, KeyError) as e:
-                logger.warning(
-                    "Buy Price from orderbook could not be determined."
-                    f"Orderbook: {order_book}"
-                 )
-                raise PricingError from e
-            logger.info(f"Buy price from orderbook {bid_strategy['price_side'].capitalize()} side "
-                        f"- top {order_book_top} order book buy rate {rate_from_l2:.8f}")
-            used_rate = rate_from_l2
-        else:
-            logger.info(f"Using Last {bid_strategy['price_side'].capitalize()} / Last Price")
-            ticker = self.exchange.fetch_ticker(pair)
-            ticker_rate = ticker[bid_strategy['price_side']]
-            if ticker['last'] and ticker_rate > ticker['last']:
-                balance = bid_strategy['ask_last_balance']
-                ticker_rate = ticker_rate + balance * (ticker['last'] - ticker_rate)
-            used_rate = ticker_rate
-
-        self._buy_rate_cache[pair] = used_rate
-
-        return used_rate
 
     def create_trade(self, pair: str) -> bool:
         """
@@ -532,7 +487,7 @@ class FreqtradeBot(LoggingMixin):
             buy_limit_requested = price
         else:
             # Calculate price
-            buy_limit_requested = self.get_buy_rate(pair, True)
+            buy_limit_requested = self.exchange.get_buy_rate(pair, True)
 
         if not buy_limit_requested:
             raise PricingError('Could not determine buy price.')
@@ -657,7 +612,7 @@ class FreqtradeBot(LoggingMixin):
         """
         Sends rpc notification when a buy cancel occurred.
         """
-        current_rate = self.get_buy_rate(trade.pair, False)
+        current_rate = self.exchange.get_buy_rate(trade.pair, False)
 
         msg = {
             'trade_id': trade.id,

tests/exchange/test_exchange.py

@@ -1684,6 +1684,50 @@ def test_fetch_l2_order_book_exception(default_conf, mocker, exchange_name):
         exchange.fetch_l2_order_book(pair='ETH/BTC', limit=50)
 
 
+@pytest.mark.parametrize("side,ask,bid,last,last_ab,expected", [
+    ('ask', 20, 19, 10, 0.0, 20),  # Full ask side
+    ('ask', 20, 19, 10, 1.0, 10),  # Full last side
+    ('ask', 20, 19, 10, 0.5, 15),  # Between ask and last
+    ('ask', 20, 19, 10, 0.7, 13),  # Between ask and last
+    ('ask', 20, 19, 10, 0.3, 17),  # Between ask and last
+    ('ask', 5, 6, 10, 1.0, 5),  # last bigger than ask
+    ('ask', 5, 6, 10, 0.5, 5),  # last bigger than ask
+    ('ask', 10, 20, None, 0.5, 10),  # last not available - uses ask
+    ('ask', 4, 5, None, 0.5, 4),  # last not available - uses ask
+    ('ask', 4, 5, None, 1, 4),  # last not available - uses ask
+    ('ask', 4, 5, None, 0, 4),  # last not available - uses ask
+    ('bid', 21, 20, 10, 0.0, 20),  # Full bid side
+    ('bid', 21, 20, 10, 1.0, 10),  # Full last side
+    ('bid', 21, 20, 10, 0.5, 15),  # Between bid and last
+    ('bid', 21, 20, 10, 0.7, 13),  # Between bid and last
+    ('bid', 21, 20, 10, 0.3, 17),  # Between bid and last
+    ('bid', 6, 5, 10, 1.0, 5),  # last bigger than bid
+    ('bid', 6, 5, 10, 0.5, 5),  # last bigger than bid
+    ('bid', 21, 20, None, 0.5, 20),  # last not available - uses bid
+    ('bid', 6, 5, None, 0.5, 5),  # last not available - uses bid
+    ('bid', 6, 5, None, 1, 5),  # last not available - uses bid
+    ('bid', 6, 5, None, 0, 5),  # last not available - uses bid
+])
+def test_get_buy_rate(mocker, default_conf, caplog, side, ask, bid,
+                      last, last_ab, expected) -> None:
+    caplog.set_level(logging.DEBUG)
+    default_conf['bid_strategy']['ask_last_balance'] = last_ab
+    default_conf['bid_strategy']['price_side'] = side
+    exchange = get_patched_exchange(mocker, default_conf)
+    mocker.patch('freqtrade.exchange.Exchange.fetch_ticker',
+                 return_value={'ask': ask, 'last': last, 'bid': bid})
+
+    assert exchange.get_buy_rate('ETH/BTC', True) == expected
+    assert not log_has("Using cached buy rate for ETH/BTC.", caplog)
+
+    assert exchange.get_buy_rate('ETH/BTC', False) == expected
+    assert log_has("Using cached buy rate for ETH/BTC.", caplog)
+    # Running a 2nd time with Refresh on!
+    caplog.clear()
+    assert exchange.get_buy_rate('ETH/BTC', True) == expected
+    assert not log_has("Using cached buy rate for ETH/BTC.", caplog)
+
+
 def make_fetch_ohlcv_mock(data):
     def fetch_ohlcv_mock(pair, timeframe, since):
         if since:

tests/test_freqtradebot.py

@@ -751,49 +751,6 @@ def test_process_informative_pairs_added(default_conf, ticker, mocker) -> None:
     assert ("ETH/BTC", default_conf["timeframe"]) in refresh_mock.call_args[0][0]
 
 
-@pytest.mark.parametrize("side,ask,bid,last,last_ab,expected", [
-    ('ask', 20, 19, 10, 0.0, 20),  # Full ask side
-    ('ask', 20, 19, 10, 1.0, 10),  # Full last side
-    ('ask', 20, 19, 10, 0.5, 15),  # Between ask and last
-    ('ask', 20, 19, 10, 0.7, 13),  # Between ask and last
-    ('ask', 20, 19, 10, 0.3, 17),  # Between ask and last
-    ('ask', 5, 6, 10, 1.0, 5),  # last bigger than ask
-    ('ask', 5, 6, 10, 0.5, 5),  # last bigger than ask
-    ('ask', 10, 20, None, 0.5, 10),  # last not available - uses ask
-    ('ask', 4, 5, None, 0.5, 4),  # last not available - uses ask
-    ('ask', 4, 5, None, 1, 4),  # last not available - uses ask
-    ('ask', 4, 5, None, 0, 4),  # last not available - uses ask
-    ('bid', 21, 20, 10, 0.0, 20),  # Full bid side
-    ('bid', 21, 20, 10, 1.0, 10),  # Full last side
-    ('bid', 21, 20, 10, 0.5, 15),  # Between bid and last
-    ('bid', 21, 20, 10, 0.7, 13),  # Between bid and last
-    ('bid', 21, 20, 10, 0.3, 17),  # Between bid and last
-    ('bid', 6, 5, 10, 1.0, 5),  # last bigger than bid
-    ('bid', 6, 5, 10, 0.5, 5),  # last bigger than bid
-    ('bid', 21, 20, None, 0.5, 20),  # last not available - uses bid
-    ('bid', 6, 5, None, 0.5, 5),  # last not available - uses bid
-    ('bid', 6, 5, None, 1, 5),  # last not available - uses bid
-    ('bid', 6, 5, None, 0, 5),  # last not available - uses bid
-])
-def test_get_buy_rate(mocker, default_conf, caplog, side, ask, bid,
-                      last, last_ab, expected) -> None:
-    caplog.set_level(logging.DEBUG)
-    default_conf['bid_strategy']['ask_last_balance'] = last_ab
-    default_conf['bid_strategy']['price_side'] = side
-    freqtrade = get_patched_freqtradebot(mocker, default_conf)
-    mocker.patch('freqtrade.exchange.Exchange.fetch_ticker',
-                 return_value={'ask': ask, 'last': last, 'bid': bid})
-
-    assert freqtrade.get_buy_rate('ETH/BTC', True) == expected
-    assert not log_has("Using cached buy rate for ETH/BTC.", caplog)
-
-    assert freqtrade.get_buy_rate('ETH/BTC', False) == expected
-    assert log_has("Using cached buy rate for ETH/BTC.", caplog)
-    # Running a 2nd time with Refresh on!
-    caplog.clear()
-    assert freqtrade.get_buy_rate('ETH/BTC', True) == expected
-    assert not log_has("Using cached buy rate for ETH/BTC.", caplog)
-
 
 def test_execute_buy(mocker, default_conf, fee, limit_buy_order, limit_buy_order_open) -> None:
     patch_RPCManager(mocker)