Problem

In openlibrary/plugins/upstream/covers.py, the manage_covers.POST handler silently returns None when the images input is missing the expected - separator. The else branch at line 196-197 only contains # ERROR and pass, so invalid requests fail with no error message or feedback to the user.

Reproducing the bug

sudo docker compose run --rm home python3 -c "
from unittest.mock import patch, MagicMock
import web
app = web.application(('/', 'x'), globals())
app.load({'REQUEST_METHOD': 'POST', 'PATH_INFO': '/'})
with patch('web.input', return_value=web.storage(image=['1', '2', '3'])):
    with patch('openlibrary.plugins.upstream.covers.accounts.get_current_user', return_value=MagicMock()):
        web.ctx.site = MagicMock()
        web.ctx.site.get.return_value = MagicMock()
        from openlibrary.plugins.upstream.covers import manage_covers
        print(manage_covers().POST('/editions/OL1M'))
"

• Expected behavior: an error response
• Actual behavior:None returned silently

Screenshot from local environment:

Context

Found in openlibrary/plugins/upstream/covers.py in manage_covers.POST around line 196-197.

Breakdown

Replace # ERROR and pass with an appropriate error response so the user receives feedback when invalid input is submitted.