refactored

src/config.py

@@ -0,0 +1,46 @@
+import os
+import json
+from dataclasses import dataclass, fields
+from typing import Any
+
+class ConfigException (Exception): pass
+
+def default_env_loader(var_name, default_value=None):
+    v = os.getenv(var_name, default_value)
+    if not v:
+        raise ConfigException(var_name)
+    return v
+
+def json_env_loader(var_name):
+    v = default_env_loader(var_name)
+    vv = json.loads(v)
+    return vv
+
+@dataclass(init=False, frozen=False)
+class Config:
+    MQTT_BROKER : str
+    MQTT_PORT : int
+    MQTT_CLIENT_PREFIX : str
+    BOXES : dict
+    BOX_TOPIC_PREFIXES : dict
+    CENTRAL_TOPICS : dict
+    OFF_TEMPERATURE : str
+    LOW_TEMPERATURE : str
+    MAINTENANCE_TEMPERATURE : str
+    DEFAULT_HIGH_TEMPERATURE : str
+    STATUS_TOPIC : str
+    CONTEXT_TOPIC_PREFIX : str
+
+    def __init__(self):
+        for f in fields(self):
+            v = os.getenv(f.name)
+            if not v:
+                raise ConfigException(f.name)
+            if f.type == int:
+                v = int(v)
+            elif f.type == dict:
+                v = json.loads(v)
+            setattr(self, f.name, v)
+
+
+