From c9e49ed7b40a541eb9d2e385d586c73eb6f22b3c Mon Sep 17 00:00:00 2001
From: Gerald Lonlas <g.lonlas@gmail.com>
Date: Thu, 31 May 2018 23:45:35 -0700
Subject: [PATCH] Sort ticker_history

CCXT does not sort the ticker history from exchanges.
Bittrex and Binance are sorted ASC (oldest first, newest last) when
GDAX is sorted DESC (newest first, oldest last).

Because of that the get_ticker_history() fall in a very long loop
when the tickers are sorted DESC. Means it downloads more than
needed.

This commit enable exhanges like GDAX and unify the ticker_history
list across all exchanges.
---
 freqtrade/exchange/__init__.py            |  5 ++
 freqtrade/tests/exchange/test_exchange.py | 72 +++++++++++++++++++++++
 2 files changed, 77 insertions(+)

diff --git a/freqtrade/exchange/__init__.py b/freqtrade/exchange/__init__.py
index 109e3f7b2..7be323329 100644
--- a/freqtrade/exchange/__init__.py
+++ b/freqtrade/exchange/__init__.py
@@ -294,6 +294,11 @@ def get_ticker_history(pair: str, tick_interval: str, since_ms: Optional[int] =
         while not since_ms or since_ms < till_time_ms:
             data_part = _API.fetch_ohlcv(pair, timeframe=tick_interval, since=since_ms)
 
+            # Because some exchange sort Tickers ASC and other DESC.
+            # Ex: Bittrex returns a list of tickers ASC (oldest first, newest last)
+            # when GDAX returns a list of tickers DESC (newest first, oldest last)
+            data_part = sorted(data_part, key=lambda x: x[0])
+
             if not data_part:
                 break
 
diff --git a/freqtrade/tests/exchange/test_exchange.py b/freqtrade/tests/exchange/test_exchange.py
index a506a8416..56812c75e 100644
--- a/freqtrade/tests/exchange/test_exchange.py
+++ b/freqtrade/tests/exchange/test_exchange.py
@@ -393,6 +393,78 @@ def test_get_ticker_history(default_conf, mocker):
         get_ticker_history('EFGH/BTC', default_conf['ticker_interval'])
 
 
+def test_get_ticker_history_sort(default_conf, mocker):
+    api_mock = MagicMock()
+
+    # GDAX use-case (real data from GDAX)
+    # This ticker history is ordered DESC (newest first, oldest last)
+    tick = [
+        [1527833100000, 0.07666, 0.07671, 0.07666, 0.07668, 16.65244264],
+        [1527832800000, 0.07662, 0.07666, 0.07662, 0.07666, 1.30051526],
+        [1527832500000, 0.07656, 0.07661, 0.07656, 0.07661, 12.034778840000001],
+        [1527832200000, 0.07658, 0.07658, 0.07655, 0.07656, 0.59780186],
+        [1527831900000, 0.07658, 0.07658, 0.07658, 0.07658, 1.76278136],
+        [1527831600000, 0.07658, 0.07658, 0.07658, 0.07658, 2.22646521],
+        [1527831300000, 0.07655, 0.07657, 0.07655, 0.07657, 1.1753],
+        [1527831000000, 0.07654, 0.07654, 0.07651, 0.07651, 0.8073060299999999],
+        [1527830700000, 0.07652, 0.07652, 0.07651, 0.07652, 10.04822687],
+        [1527830400000, 0.07649, 0.07651, 0.07649, 0.07651, 2.5734867]
+    ]
+    type(api_mock).has = PropertyMock(return_value={'fetchOHLCV': True})
+    api_mock.fetch_ohlcv = MagicMock(side_effect=make_fetch_ohlcv_mock(tick))
+    mocker.patch('freqtrade.exchange._API', api_mock)
+
+    # Test the ticker history sort
+    ticks = get_ticker_history('ETH/BTC', default_conf['ticker_interval'])
+    assert ticks[0][0] == 1527830400000
+    assert ticks[0][1] == 0.07649
+    assert ticks[0][2] == 0.07651
+    assert ticks[0][3] == 0.07649
+    assert ticks[0][4] == 0.07651
+    assert ticks[0][5] == 2.5734867
+
+    assert ticks[9][0] == 1527833100000
+    assert ticks[9][1] == 0.07666
+    assert ticks[9][2] == 0.07671
+    assert ticks[9][3] == 0.07666
+    assert ticks[9][4] == 0.07668
+    assert ticks[9][5] == 16.65244264
+
+    # Bittrex use-case (real data from Bittrex)
+    # This ticker history is ordered ASC (oldest first, newest last)
+    tick = [
+        [1527827700000, 0.07659999, 0.0766, 0.07627, 0.07657998, 1.85216924],
+        [1527828000000, 0.07657995, 0.07657995, 0.0763, 0.0763, 26.04051037],
+        [1527828300000, 0.0763, 0.07659998, 0.0763, 0.0764, 10.36434124],
+        [1527828600000, 0.0764, 0.0766, 0.0764, 0.0766, 5.71044773],
+        [1527828900000, 0.0764, 0.07666998, 0.0764, 0.07666998, 47.48888565],
+        [1527829200000, 0.0765, 0.07672999, 0.0765, 0.07672999, 3.37640326],
+        [1527829500000, 0.0766, 0.07675, 0.0765, 0.07675, 8.36203831],
+        [1527829800000, 0.07675, 0.07677999, 0.07620002, 0.076695, 119.22963884],
+        [1527830100000, 0.076695, 0.07671, 0.07624171, 0.07671, 1.80689244],
+        [1527830400000, 0.07671, 0.07674399, 0.07629216, 0.07655213, 2.31452783]
+    ]
+    type(api_mock).has = PropertyMock(return_value={'fetchOHLCV': True})
+    api_mock.fetch_ohlcv = MagicMock(side_effect=make_fetch_ohlcv_mock(tick))
+    mocker.patch('freqtrade.exchange._API', api_mock)
+
+    # Test the ticker history sort
+    ticks = get_ticker_history('ETH/BTC', default_conf['ticker_interval'])
+    assert ticks[0][0] == 1527827700000
+    assert ticks[0][1] == 0.07659999
+    assert ticks[0][2] == 0.0766
+    assert ticks[0][3] == 0.07627
+    assert ticks[0][4] == 0.07657998
+    assert ticks[0][5] == 1.85216924
+
+    assert ticks[9][0] == 1527830400000
+    assert ticks[9][1] == 0.07671
+    assert ticks[9][2] == 0.07674399
+    assert ticks[9][3] == 0.07629216
+    assert ticks[9][4] == 0.07655213
+    assert ticks[9][5] == 2.31452783
+
+
 def test_cancel_order_dry_run(default_conf, mocker):
     default_conf['dry_run'] = True
     mocker.patch.dict('freqtrade.exchange._CONF', default_conf)