Re-indexing showcases fails on CKAN 2.9

[stefina]

Hey there, we have started to upgrade one of our instances from 2.8.4 to CKAN 2.9.2.

Now we are running into issues when rebuilding the index. Datasets get re-indexed just fine but it fails for showcases with this error-message:

2021-09-16 12:49:12,465 INFO  [ckan.lib.search] Rebuilding search index...
No object (name: tmpl_context or C) has been registered for this thread
2021-09-16 12:49:12,517 INFO  [ckan.lib.search] Commited pending changes on the search index

We found so far, that those kind of errors have to do with Pylons and Flask interfering but I wasn't able to pin down why this happens only for showcases as we are using the most recent version 1.4.4 which is described as compatible with CKAN 2.9

Additional Notes:

• we are running CKAN 2.9 (and CKAN 2.8 before) in a container with docker-compose per official CKAN setup
• we are experiencing this locally with a dump from our production-instance
• we ran the migrate_package_activity.py script which will also present errors but when navigating to the showcases directly we can display them as well as the activities

[stefina]

We found the issue in two of our plugins which was the culprit that we didn't find it quickly (commenting out custom code made this occur in the other portion of the custom code). We were modifying the before_search-result by checking g.user but that threw that exception above. We are now excepting the TypeError that is thrown there.