feat: expand env variables in config at runtime

README.md

@@ -59,6 +59,8 @@ The default values are below.
 `ntfy.server` (string url) Ntfy server to use.
 `ntfy.topic` (string) Ntfy topic for the notification.
 
+Note : `$` will be expanded into the environment variables at runtime. Don't forget to escape it with `\`.
+
 ### Usage
 
 * Adding a PR : `nixpkgs-notifier add PR1 PR2 PR3 ...`

nixpkgs_notifier.py

@@ -74,6 +74,32 @@ def load_config():
         print("Config file is broken. Using default config.")
         return DEFAULT_CONFIG
 
+import re
+
+def expand_env_vars(obj):
+    if isinstance(obj, dict):
+        return {
+            key: expand_env_vars(value)
+            for key, value in obj.items()
+        }
+
+    elif isinstance(obj, list):
+        return [
+            expand_env_vars(item)
+            for item in obj
+        ]
+
+    elif isinstance(obj, str):
+        pattern = r"(?<!\\)\$([A-Za-z_][A-Za-z0-9_]*)"
+
+        def replace(match):
+            var = match.group(1)
+            return os.environ.get(var, match.group(0))
+
+        return re.sub(pattern, replace, obj)
+
+    return obj
+
 def addTracker(PRnumber):
     result = fetchStatus(PRnumber)
     if result == "accepted":
@@ -237,7 +263,7 @@ def fetchStatus(PRnumber):
 
 def main():
     # fetch config
-    cfg = load_config()
+    cfg = expand_env_vars(load_config())
 
     global configTime
     global configFetchTime