When finding new files/messages/replies, work back in time

Retrieving submissions and replies for the most recently active
sources first will make the initial sync feel faster, as the visible
part of the source list is updated first, and will make it possible to
for journalists to work with what are likely the most interesting
sources sooner.

Author: rmol

securedrop_client/storage.py

@@ -429,7 +429,9 @@ def update_draft_replies(
 
 
 def find_new_files(session: Session) -> List[File]:
-    return session.query(File).filter_by(is_downloaded=False).all()
+    q = session.query(File).join(Source).filter_by(is_downloaded=False)
+    q = q.order_by(desc(Source.last_updated))
+    return q.all()
 
 
 def find_new_messages(session: Session) -> List[Message]:
@@ -441,10 +443,15 @@ def find_new_messages(session: Session) -> List[Message]:
     * The message has not yet had decryption attempted.
     * Decryption previously failed on a message.
     """
-    return session.query(Message).filter(
-        or_(Message.is_downloaded == False,
+    q = session.query(Message).join(Source).filter(
+        or_(
+            Message.is_downloaded == False,
             Message.is_decrypted == False,
-            Message.is_decrypted == None)).all()  # noqa: E711
+            Message.is_decrypted == None
+        )
+    )  # noqa: E712
+    q = q.order_by(desc(Source.last_updated))
+    return q.all()
 
 
 def find_new_replies(session: Session) -> List[Reply]:
@@ -456,10 +463,15 @@ def find_new_replies(session: Session) -> List[Reply]:
     * The reply has not yet had decryption attempted.
     * Decryption previously failed on a reply.
     """
-    return session.query(Reply).filter(
-        or_(Reply.is_downloaded == False,
+    q = session.query(Reply).join(Source).filter(
+        or_(
+            Reply.is_downloaded == False,
             Reply.is_decrypted == False,
-            Reply.is_decrypted == None)).all()  # noqa: E711
+            Reply.is_decrypted == None
+        )
+    )  # noqa: E712
+    q = q.order_by(desc(Source.last_updated))
+    return q.all()
 
 
 def mark_as_not_downloaded(uuid: str, session: Session) -> None:

tests/test_storage.py

@@ -903,7 +903,7 @@ def test_find_new_files(mocker, session):
     mock_submission = mocker.MagicMock()
     mock_submission.is_downloaded = False
     mock_submissions = [mock_submission]
-    mock_session.query().filter_by().all.return_value = mock_submissions
+    mock_session.query().join().filter_by().order_by().all.return_value = mock_submissions
     submissions = find_new_files(mock_session)
     assert submissions[0].is_downloaded is False