Okx - conditional candle-length

tests/exchange/test_ccxt_compat.py

@@ -13,6 +13,7 @@ import pytest
 
 from freqtrade.enums import CandleType
 from freqtrade.exchange import timeframe_to_minutes, timeframe_to_prev_date
+from freqtrade.exchange.exchange import timeframe_to_msecs
 from freqtrade.resolvers.exchange_resolver import ExchangeResolver
 from tests.conftest import get_default_conf_usdt
 
@@ -236,6 +237,38 @@ class TestCCXTExchange():
         now = datetime.now(timezone.utc) - timedelta(minutes=(timeframe_to_minutes(timeframe) * 2))
         assert exchange.klines(pair_tf).iloc[-1]['date'] >= timeframe_to_prev_date(timeframe, now)
 
+    def test_ccxt__async_get_candle_history(self, exchange):
+        exchange, exchangename = exchange
+        # For some weired reason, this test returns random lengths for bittrex.
+        if not exchange._ft_has['ohlcv_has_history'] or exchangename == 'bittrex':
+            return
+        pair = EXCHANGES[exchangename]['pair']
+        timeframe = EXCHANGES[exchangename]['timeframe']
+        candle_type = CandleType.SPOT
+        timeframe_ms = timeframe_to_msecs(timeframe)
+        now = timeframe_to_prev_date(
+                timeframe, datetime.now(timezone.utc))
+        for offset in (360, 120, 30, 10, 5, 2):
+            since = now - timedelta(days=offset)
+            since_ms = int(since.timestamp() * 1000)
+
+            res = exchange.loop.run_until_complete(exchange._async_get_candle_history(
+                pair=pair,
+                timeframe=timeframe,
+                since_ms=since_ms,
+                candle_type=candle_type
+            )
+            )
+            assert res
+            assert res[0] == pair
+            assert res[1] == timeframe
+            assert res[2] == candle_type
+            candles = res[3]
+            candle_count = exchange.ohlcv_candle_limit(timeframe, candle_type, since_ms) * 0.9
+            candle_count1 = (now.timestamp() * 1000 - since_ms) // timeframe_ms
+            assert len(candles) >= min(candle_count, candle_count1)
+            assert candles[0][0] == since_ms or (since_ms + timeframe_ms)
+
     def test_ccxt_fetch_funding_rate_history(self, exchange_futures):
         exchange, exchangename = exchange_futures
         if not exchange: