Unified processing of last change times of posts

owl/background.py

@@ -119,7 +119,7 @@ def send_notify_to_dest(post: db.Post, topic: db.Topic, course: db.Course, autho
     msg['From'] = email.headerregistry.Address(display_name=author.full_name() + " via Owl", addr_spec=app.config['MAIL_FROM'])
     msg['To'] = email.headerregistry.Address(display_name=dest.full_name(), addr_spec=dest.email)
     msg['Subject'] = f'Owl: {topic.title}'
-    msg['Date'] = (post.modified or post.created).astimezone()
+    msg['Date'] = post.last_change_time().astimezone()
     if 'MAIL_REFERENCES' in app.config:
         # Everybody gets his own view of the thread, so the target is the observer's uid
         msg['References'] = '<' + app.config['MAIL_REFERENCES'].format(tid=post.tid, target=dest.uid) + '>'

owl/course.py

@@ -174,9 +174,8 @@ def topic_index(sident: str, cident: str, tident: str, student_uid: Optional[int
                    topic=g.topic)
     )
 
-    post_times = [p.created for p in posts] + [p.modified for p in posts if p.modified is not None]
-    if post_times:
-        last_post_time = max(post_times)
+    if posts:
+        last_post_time = max(p.last_change_time() for p in posts)
         if seen is None or seen < last_post_time:
             form.ack_time.data = last_post_time
 

owl/db.py

 # SQLAlchemy definitions of all tables in the database
 # Generated by sqlacodegen and then heavily edited.
 
+import datetime
 from sqlalchemy import Boolean, CHAR, Column, DateTime, ForeignKey, Integer, Numeric, String, Text, UniqueConstraint, text
 from sqlalchemy.orm import relationship, Session
 from sqlalchemy.ext.declarative import declarative_base
@@ -116,6 +117,12 @@ class Post(Base):
     target = relationship('User', primaryjoin='Post.target_uid == User.uid')
     topic = relationship('Topic')
 
+    def last_change_time(self) -> datetime.datetime:
+        if self.modified is not None:
+            return self.modified
+        else:
+            return self.created
+
 
 class Seen(Base):
     __tablename__ = 'owl_seen'

owl/teacher.py

@@ -87,10 +87,9 @@ def teacher(sident: str, cident: str):
         sol = solutions[p.target_uid][p.tid]
         if p.points is not None:
             sol.points = p.points
-        if sol.last_activity is None or sol.last_activity < p.created:
-            sol.last_activity = p.created
-        if p.modified is not None and sol.last_activity < p.modified:
-            sol.last_activity = p.modified
+        mtime = p.last_change_time()
+        if sol.last_activity is None or sol.last_activity < mtime:
+            sol.last_activity = mtime
 
     totals: Dict[int, Decimal] = {}
     for u in solutions.keys():