Add environment variable support

freqtrade/configuration/environment_vars.py

@@ -0,0 +1,54 @@
+import logging
+import os
+from typing import Any, Dict
+
+from freqtrade.constants import ENV_VAR_PREFIX
+from freqtrade.misc import deep_merge_dicts
+
+
+logger = logging.getLogger(__name__)
+
+
+def get_var_typed(val):
+    try:
+        return int(val)
+    except ValueError:
+        try:
+            return float(val)
+        except ValueError:
+            if val.lower() in ('t', 'true'):
+                return True
+            elif val.lower() in ('f', 'false'):
+                return False
+    # keep as string
+    return val
+
+
+def flat_vars_to_nested_dict(env_dict: Dict[str, Any], prefix: str) -> Dict[str, Any]:
+    """
+    Environment variables must be prefixed with FREQTRADE.
+    FREQTRADE__{section}__{key}
+    :param env_dict: Dictionary to validate - usually os.environ
+    :param prefix: Prefix to consider (usually FREQTRADE__)
+    :return: Nested dict based on available and relevant variables.
+    """
+    relevant_vars: Dict[str, Any] = {}
+
+    for env_var, val in sorted(env_dict.items()):
+        if env_var.startswith(prefix):
+            logger.info(f"Loading variable '{env_var}'")
+            key = env_var.replace(prefix, '')
+            for k in reversed(key.split('__')):
+                val = {k.lower(): get_var_typed(val) if type(val) != dict else val}
+            relevant_vars = deep_merge_dicts(val, relevant_vars)
+
+    return relevant_vars
+
+
+def enironment_vars_to_dict() -> Dict[str, Any]:
+    """
+    Read environment variables and return a nested dict for relevant variables
+    Relevant variables must follow the FREQTRADE__{section}__{key} pattern
+    :return: Nested dict based on available and relevant variables.
+    """
+    return flat_vars_to_nested_dict(os.environ.copy(), ENV_VAR_PREFIX)