Merge branch 'develop' into feat_readjust_entry

docs/strategy-callbacks.md

@@ -7,6 +7,7 @@ Depending on the callback used, they may be called when entering / exiting a tra
 
 Currently available callbacks:
 
+* [`bot_start()`](#bot-start)
 * [`bot_loop_start()`](#bot-loop-start)
 * [`custom_stake_amount()`](#stake-size-management)
 * [`custom_exit()`](#custom-exit-signal)
@@ -22,6 +23,29 @@ Currently available callbacks:
 !!! Tip "Callback calling sequence"
     You can find the callback calling sequence in [bot-basics](bot-basics.md#bot-execution-logic)
 
+## Bot start
+
+A simple callback which is called once when the strategy is loaded.
+This can be used to perform actions that must only be performed once and runs after dataprovider and wallet are set
+
+``` python
+import requests
+
+class AwesomeStrategy(IStrategy):
+
+    # ... populate_* methods
+
+    def bot_start(self, **kwargs) -> None:
+        """
+        Called only once after bot instantiation.
+        :param **kwargs: Ensure to keep this here so updates to this won't break your strategy.
+        """
+        if self.config['runmode'].value in ('live', 'dry_run'):
+            # Assign this to the class by using self.*
+            # can then be used by populate_* methods
+            self.cust_remote_data = requests.get('https://some_remote_source.example.com')
+
+```
 ## Bot loop start
 
 A simple callback which is called once at the start of every bot throttling iteration (roughly every 5 seconds, unless configured differently).