Refactoring _process/throttle to let throttle handle cases when we need an extra sleep time due to poor exchange conditions

freqtrade/main.py

@@ -92,14 +92,17 @@ def process_maybe_execute_sell(trade, interval):
     return False
 
 
-def _process(interval: int, nb_assets: Optional[int] = 0) -> bool:
+def _process(interval: int, nb_assets: Optional[int] = 0) -> (bool, int):
     """
     Queries the persistence layer for open trades and handles them,
     otherwise a new trade is created.
     :param: nb_assets: the maximum number of pairs to be traded at the same time
-    :return: True if one or more trades has been created or closed, False otherwise
+    :return: a pair, the first value is True if one or more trades has been created
+    or closed, False otherwise, the second argument is a requested sleep time in
+     seconds to be used when exchange is having problems
     """
     state_changed = False
+    extra_time = 0
     try:
         # Refresh whitelist based on wallet maintenance
         sanitized_list = refresh_whitelist(
@@ -130,7 +133,7 @@ def _process(interval: int, nb_assets: Optional[int] = 0) -> bool:
             'Got %s in _process(), retrying in 30 seconds...',
             error
         )
-        time.sleep(30)
+        extra_time = 30
     except OperationalException:
         rpc.send_msg('*Status:* Got OperationalException:\n```\n{traceback}```{hint}'.format(
             traceback=traceback.format_exc(),
@@ -138,7 +141,7 @@ def _process(interval: int, nb_assets: Optional[int] = 0) -> bool:
         ))
         logger.exception('Got OperationalException. Stopping trader ...')
         update_state(State.STOPPED)
-    return state_changed
+    return state_changed, extra_time
 
 
 # FIX: 20180110, why is cancel.order unconditionally here, whereas

freqtrade/misc.py

@@ -115,9 +115,9 @@ def throttle(func: Callable[..., Any], min_secs: float, *args, **kwargs) -> Any:
     :return: Any
     """
     start = time.time()
-    result = func(*args, **kwargs)
+    (result, extra_time)  = func(*args, **kwargs)
     end = time.time()
-    duration = max(min_secs - (end - start), 0.0)
+    duration = max(max(min_secs - (end - start), 0.0), extra_time)
     logger.debug('Throttling %s for %.2f seconds', func.__name__, duration)
     time.sleep(duration)
     return result

freqtrade/tests/test_main.py

@@ -91,7 +91,7 @@ def test_process_trade_creation(default_conf, ticker, limit_buy_order, health, m
     assert not trades
 
     result = _process(interval=int(default_conf['ticker_interval']))
-    assert result is True
+    assert result == (True, 0)
 
     trades = Trade.query.filter(Trade.is_open.is_(True)).all()
     assert len(trades) == 1
@@ -117,7 +117,7 @@ def test_process_exchange_failures(default_conf, ticker, health, mocker):
                           buy=MagicMock(side_effect=requests.exceptions.RequestException))
     init(default_conf, create_engine('sqlite://'))
     result = _process(interval=int(default_conf['ticker_interval']))
-    assert result is False
+    assert result == (False, 30)
     assert sleep_mock.has_calls()
 
 
@@ -135,7 +135,7 @@ def test_process_operational_exception(default_conf, ticker, health, mocker):
     assert get_state() == State.RUNNING
 
     result = _process(interval=int(default_conf['ticker_interval']))
-    assert result is False
+    assert result == (False, 0)
     assert get_state() == State.STOPPED
     assert 'OperationalException' in msg_mock.call_args_list[-1][0][0]
 
@@ -155,12 +155,12 @@ def test_process_trade_handling(default_conf, ticker, limit_buy_order, health, m
     trades = Trade.query.filter(Trade.is_open.is_(True)).all()
     assert not trades
     result = _process(interval=int(default_conf['ticker_interval']))
-    assert result is True
+    assert result == (True, 0)
     trades = Trade.query.filter(Trade.is_open.is_(True)).all()
     assert len(trades) == 1
 
     result = _process(interval=int(default_conf['ticker_interval']))
-    assert result is False
+    assert result == (False, 0)
 
 
 def test_create_trade(default_conf, ticker, limit_buy_order, mocker):

freqtrade/tests/test_misc.py

@@ -16,7 +16,7 @@ from freqtrade.misc import (common_args_parser, file_dump_json, load_config,
 def test_throttle():
 
     def func():
-        return 42
+        return (42, 1)
 
     start = time.time()
     result = throttle(func, min_secs=0.1)
@@ -32,7 +32,7 @@ def test_throttle():
 def test_throttle_with_assets():
 
     def func(nb_assets=-1):
-        return nb_assets
+        return (nb_assets, 0)
 
     result = throttle(func, min_secs=0.1, nb_assets=666)
     assert result == 666