Add ccxt_sync_config to simplify ccxt configuration

docs/configuration.md

@@ -83,7 +83,8 @@ Mandatory parameters are marked as **Required**, which means that they are requi
 | `exchange.password` | API password to use for the exchange. Only required when you are in production mode and for exchanges that use password for API requests.<br>**Keep it in secret, do not disclose publicly.** <br> **Datatype:** String
 | `exchange.pair_whitelist` | List of pairs to use by the bot for trading and to check for potential trades during backtesting. Not used by VolumePairList (see [below](#pairlists-and-pairlist-handlers)). <br> **Datatype:** List
 | `exchange.pair_blacklist` | List of pairs the bot must absolutely avoid for trading and backtesting (see [below](#pairlists-and-pairlist-handlers)). <br> **Datatype:** List
-| `exchange.ccxt_config` | Additional CCXT parameters passed to the regular ccxt instance. Parameters may differ from exchange to exchange and are documented in the [ccxt documentation](https://ccxt.readthedocs.io/en/latest/manual.html#instantiation) <br> **Datatype:** Dict
+| `exchange.ccxt_config` | Additional CCXT parameters passed to both ccxt instances. This is usually the correct place for ccxt configurations. Parameters may differ from exchange to exchange and are documented in the [ccxt documentation](https://ccxt.readthedocs.io/en/latest/manual.html#instantiation) <br> **Datatype:** Dict
+| `exchange.ccxt_sync_config` | Additional CCXT parameters passed to the regular (sync) ccxt instance. Parameters may differ from exchange to exchange and are documented in the [ccxt documentation](https://ccxt.readthedocs.io/en/latest/manual.html#instantiation) <br> **Datatype:** Dict
 | `exchange.ccxt_async_config` | Additional CCXT parameters passed to the async ccxt instance. Parameters may differ from exchange to exchange  and are documented in the [ccxt documentation](https://ccxt.readthedocs.io/en/latest/manual.html#instantiation) <br> **Datatype:** Dict
 | `exchange.markets_refresh_interval` | The interval in minutes in which markets are reloaded. <br>*Defaults to `60` minutes.* <br> **Datatype:** Positive Integer
 | `edge.*` | Please refer to [edge configuration document](edge.md) for detailed explanation.

freqtrade/exchange/exchange.py

@@ -98,12 +98,14 @@ class Exchange:
 
         # Initialize ccxt objects
         ccxt_config = self._ccxt_config.copy()
-        ccxt_config = deep_merge_dicts(exchange_config.get('ccxt_config', {}),
-                                       ccxt_config)
-        self._api = self._init_ccxt(
-            exchange_config, ccxt_kwargs=ccxt_config)
+        ccxt_config = deep_merge_dicts(exchange_config.get('ccxt_config', {}), ccxt_config)
+        ccxt_config = deep_merge_dicts(exchange_config.get('ccxt_sync_config', {}), ccxt_config)
+
+        self._api = self._init_ccxt(exchange_config, ccxt_kwargs=ccxt_config)
 
         ccxt_async_config = self._ccxt_config.copy()
+        ccxt_async_config = deep_merge_dicts(exchange_config.get('ccxt_config', {}),
+                                             ccxt_async_config)
         ccxt_async_config = deep_merge_dicts(exchange_config.get('ccxt_async_config', {}),
                                              ccxt_async_config)
         self._api_async = self._init_ccxt(

tests/exchange/test_exchange.py

@@ -88,15 +88,19 @@ def test_init_ccxt_kwargs(default_conf, mocker, caplog):
     caplog.clear()
     conf = copy.deepcopy(default_conf)
     conf['exchange']['ccxt_config'] = {'TestKWARG': 11}
+    conf['exchange']['ccxt_sync_config'] = {'TestKWARG44': 11}
     conf['exchange']['ccxt_async_config'] = {'asyncio_loop': True}
-
+    asynclogmsg = "Applying additional ccxt config: {'TestKWARG': 11, 'asyncio_loop': True}"
     ex = Exchange(conf)
-    assert not log_has("Applying additional ccxt config: {'aiohttp_trust_env': True}", caplog)
     assert not ex._api_async.aiohttp_trust_env
     assert hasattr(ex._api, 'TestKWARG')
     assert ex._api.TestKWARG == 11
-    assert not hasattr(ex._api_async, 'TestKWARG')
-    assert log_has("Applying additional ccxt config: {'TestKWARG': 11}", caplog)
+    # ccxt_config is assigned to both sync and async
+    assert not hasattr(ex._api_async, 'TestKWARG44')
+
+    assert hasattr(ex._api_async, 'TestKWARG')
+    assert log_has("Applying additional ccxt config: {'TestKWARG': 11, 'TestKWARG44': 11}", caplog)
+    assert log_has(asynclogmsg, caplog)
 
 
 def test_destroy(default_conf, mocker, caplog):