Add binance futures mode checks

closes #7505

docs/exchanges.md

@@ -60,11 +60,18 @@ Binance supports [time_in_force](configuration.md#understand-order_time_in_force
     Binance supports `stoploss_on_exchange` and uses `stop-loss-limit` orders. It provides great advantages, so we recommend to benefit from it by enabling stoploss on exchange.
     On futures, Binance supports both `stop-limit` as well as `stop-market` orders. You can use either `"limit"` or `"market"` in the `order_types.stoploss` configuration setting to decide which type to use.
 
-### Binance Blacklist
+### Binance Blacklist recommendation
 
 For Binance, it is suggested to add `"BNB/<STAKE>"` to your blacklist to avoid issues, unless you are willing to maintain enough extra `BNB` on the account or unless you're willing to disable using `BNB` for fees.
 Binance accounts may use `BNB` for fees, and if a trade happens to be on `BNB`, further trades may consume this position and make the initial BNB trade unsellable as the expected amount is not there anymore.
 
+### Binance sites
+
+Binance has been split into 2, and users must use the correct ccxt exchange ID for their exchange, otherwise API keys are not recognized.
+
+* [binance.com](https://www.binance.com/) - International users. Use exchange id: `binance`.
+* [binance.us](https://www.binance.us/) - US based users. Use exchange id: `binanceus`.
+
 ### Binance Futures
 
 Binance has specific (unfortunately complex) [Futures Trading Quantitative Rules](https://www.binance.com/en/support/faq/4f462ebe6ff445d4a170be7d9e897272) which need to be followed, and which prohibit a too low stake-amount (among others) for too many orders.
@@ -87,12 +94,14 @@ When trading on Binance Futures market, orderbook must be used because there is
   },
 ```
 
-### Binance sites
+#### Binance futures settings
 
-Binance has been split into 2, and users must use the correct ccxt exchange ID for their exchange, otherwise API keys are not recognized.
+Users will also have to have the futures-setting "Position Mode" set to "One-way Mode", and "Asset Mode" set to "Single-Asset Mode".
+These settings will be checked on startup, and freqtrade will show an error if this setting is wrong.
 
-* [binance.com](https://www.binance.com/) - International users. Use exchange id: `binance`.
-* [binance.us](https://www.binance.us/) - US based users. Use exchange id: `binanceus`.
+![Binance futures settings](assets/binance_futures_settings.png)
+
+Freqtrade will not attempt to change these settings.
 
 ## Kraken
 

freqtrade/exchange/binance.py

@@ -68,6 +68,37 @@ class Binance(Exchange):
             tickers = deep_merge_dicts(bidsasks, tickers, allow_null_overrides=False)
         return tickers
 
+    @retrier
+    def additional_exchange_init(self) -> None:
+        """
+        Additional exchange initialization logic.
+        .api will be available at this point.
+        Must be overridden in child methods if required.
+        """
+        try:
+            if self.trading_mode == TradingMode.FUTURES and not self._config['dry_run']:
+                position_side = self._api.fapiPrivateGetPositionsideDual()
+                self._log_exchange_response('position_side_setting', position_side)
+                assets_margin = self._api.fapiPrivateGetMultiAssetsMargin()
+                self._log_exchange_response('multi_asset_margin', assets_margin)
+                msg = ""
+                if position_side.get('dualSidePosition') is True:
+                    msg += (
+                        "\nHedge Mode is not supported by freqtrade. "
+                        "Please change 'Position Mode' on your binance futures account.")
+                if assets_margin.get('multiAssetsMargin') is True:
+                    msg += ("\nMulti-Asset Mode is not supported by freqtrade. "
+                            "Please change 'Asset Mode' on your binance futures account.")
+                if msg:
+                    raise OperationalException(msg)
+        except ccxt.DDoSProtection as e:
+            raise DDosProtection(e) from e
+        except (ccxt.NetworkError, ccxt.ExchangeError) as e:
+            raise TemporaryError(
+                f'Could not set leverage due to {e.__class__.__name__}. Message: {e}') from e
+        except ccxt.BaseError as e:
+            raise OperationalException(e) from e
+
     @retrier
     def _set_leverage(
         self,

tests/exchange/test_binance.py

@@ -501,6 +501,24 @@ def test_fill_leverage_tiers_binance_dryrun(default_conf, mocker, leverage_tiers
         assert len(v) == len(value)
 
 
+def test_additional_exchange_init_binance(default_conf, mocker):
+    api_mock = MagicMock()
+    api_mock.fapiPrivateGetPositionsideDual = MagicMock(return_value={"dualSidePosition": True})
+    api_mock.fapiPrivateGetMultiAssetsMargin = MagicMock(return_value={"multiAssetsMargin": True})
+    default_conf['dry_run'] = False
+    default_conf['trading_mode'] = TradingMode.FUTURES
+    default_conf['margin_mode'] = MarginMode.ISOLATED
+    with pytest.raises(OperationalException,
+                       match=r"Hedge Mode is not supported.*\nMulti-Asset Mode is not supported.*"):
+        get_patched_exchange(mocker, default_conf, id="binance", api_mock=api_mock)
+    api_mock.fapiPrivateGetPositionsideDual = MagicMock(return_value={"dualSidePosition": False})
+    api_mock.fapiPrivateGetMultiAssetsMargin = MagicMock(return_value={"multiAssetsMargin": False})
+    exchange = get_patched_exchange(mocker, default_conf, id="binance", api_mock=api_mock)
+    assert exchange
+    ccxt_exceptionhandlers(mocker, default_conf, api_mock, 'binance',
+                           "additional_exchange_init", "fapiPrivateGetPositionsideDual")
+
+
 def test__set_leverage_binance(mocker, default_conf):
 
     api_mock = MagicMock()

tests/exchange/test_ccxt_compat.py

@@ -137,6 +137,7 @@ def exchange_futures(request, exchange_conf, class_mocker):
             'freqtrade.exchange.binance.Binance.fill_leverage_tiers')
         class_mocker.patch('freqtrade.exchange.exchange.Exchange.fetch_trading_fees')
         class_mocker.patch('freqtrade.exchange.okx.Okx.additional_exchange_init')
+        class_mocker.patch('freqtrade.exchange.binance.Binance.additional_exchange_init')
         class_mocker.patch('freqtrade.exchange.exchange.Exchange.load_cached_leverage_tiers',
                            return_value=None)
         class_mocker.patch('freqtrade.exchange.exchange.Exchange.cache_leverage_tiers')