Fixed a bug, added documentation and type annotations

outage_detector/main.py

@@ -1,6 +1,6 @@
 import sys
 import argparse
-from datetime import datetime
+from datetime import datetime, timedelta
 
 import requests
 
@@ -27,18 +27,27 @@ class Outage:
         Could be None to represent that the outage is still ongoing.
     '''
 
-    def __init__(self, start: LogEntry, end: None | LogEntry = None):
+    def __init__(self, start: LogEntry, end: None | LogEntry = None) -> None:
+        '''
+            Initialize an outage.
+
+            `start` The start of an outage represented by a LogEntry object.
+
+            `end` The end of an outage represented by a LogEntry object.
+            By default it is none to represent an ongoing outage.
+        '''
+
         self.start = start
         self.end = end
 
-    def duration(self) -> datetime:
+    def duration(self) -> timedelta:
         '''
             Return the duration of the outage as datetime object.
             If the outage does not have an end, the time from the start to now will be returned.
         '''
 
         if self.end is None:
-            return self.end.date - datetime.now()
+            return datetime.now() - self.start.date
         else:
             return self.end.date - self.start.date