rework exception handling (fixes #108)

freqtrade/main.py

@@ -14,7 +14,8 @@ from jsonschema import validate
 
 from freqtrade import __version__, exchange, persistence
 from freqtrade.analyze import get_buy_signal
-from freqtrade.misc import CONF_SCHEMA, State, get_state, update_state, build_arg_parser, throttle
+from freqtrade.misc import CONF_SCHEMA, State, get_state, update_state, build_arg_parser, throttle, \
+    FreqtradeException
 from freqtrade.persistence import Trade
 from freqtrade.rpc import telegram
 
@@ -76,8 +77,8 @@ def _process(dynamic_whitelist: Optional[bool] = False) -> bool:
                         'Checked all whitelisted currencies. '
                         'Found no suitable entry positions for buying. Will keep looking ...'
                     )
-            except ValueError:
+            except FreqtradeException as e:
-                logger.exception('Unable to create trade')
+                logger.warning('Unable to create trade: %s', e)
 
         for trade in trades:
             # Get order details for actual price per unit
@@ -93,7 +94,7 @@ def _process(dynamic_whitelist: Optional[bool] = False) -> bool:
             Trade.session.flush()
     except (requests.exceptions.RequestException, json.JSONDecodeError) as error:
         msg = 'Got {} in _process(), retrying in 30 seconds...'.format(error.__class__.__name__)
-        logger.exception(msg)
+        logger.warning(msg)
         time.sleep(30)
     except RuntimeError:
         telegram.send_msg('*Status:* Got RuntimeError:\n```\n{traceback}```{hint}'.format(
@@ -206,7 +207,7 @@ def create_trade(stake_amount: float) -> Optional[Trade]:
     whitelist = copy.deepcopy(_CONF['exchange']['pair_whitelist'])
     # Check if stake_amount is fulfilled
     if exchange.get_balance(_CONF['stake_currency']) < stake_amount:
-        raise ValueError(
+        raise FreqtradeException(
             'stake amount is not fulfilled (currency={})'.format(_CONF['stake_currency'])
         )
 
@@ -216,7 +217,7 @@ def create_trade(stake_amount: float) -> Optional[Trade]:
             whitelist.remove(trade.pair)
             logger.debug('Ignoring %s in pair whitelist', trade.pair)
     if not whitelist:
-        raise ValueError('No pair in whitelist')
+        raise FreqtradeException('No pair in whitelist')
 
     # Pick pair based on StochRSI buy signals
     for _pair in whitelist:

freqtrade/misc.py

@@ -11,6 +11,10 @@ from freqtrade import __version__
 logger = logging.getLogger(__name__)
 
 
+class FreqtradeException(BaseException):
+    pass
+
+
 class State(enum.Enum):
     RUNNING = 0
     STOPPED = 1

freqtrade/tests/test_main.py

@@ -9,7 +9,7 @@ from sqlalchemy import create_engine
 from freqtrade.exchange import Exchanges
 from freqtrade.main import create_trade, handle_trade, close_trade_if_fulfilled, init, \
     get_target_bid, _process
-from freqtrade.misc import get_state, State
+from freqtrade.misc import get_state, State, FreqtradeException
 from freqtrade.persistence import Trade
 
 
@@ -139,7 +139,7 @@ def test_create_trade_no_stake_amount(default_conf, ticker, mocker):
                           get_ticker=ticker,
                           buy=MagicMock(return_value='mocked_limit_buy'),
                           get_balance=MagicMock(return_value=default_conf['stake_amount'] * 0.5))
-    with pytest.raises(ValueError, match=r'.*stake amount.*'):
+    with pytest.raises(FreqtradeException, match=r'.*stake amount.*'):
         create_trade(default_conf['stake_amount'])
 
 
@@ -152,7 +152,7 @@ def test_create_trade_no_pairs(default_conf, ticker, mocker):
                           get_ticker=ticker,
                           buy=MagicMock(return_value='mocked_limit_buy'))
 
-    with pytest.raises(ValueError, match=r'.*No pair in whitelist.*'):
+    with pytest.raises(FreqtradeException, match=r'.*No pair in whitelist.*'):
         conf = copy.deepcopy(default_conf)
         conf['exchange']['pair_whitelist'] = []
         mocker.patch.dict('freqtrade.main._CONF', conf)