fix: "Explore courses" search wasn't working with Typesense

[bradenmacdonald]

Browsing courses at http://apps.local.openedx.io:1998/catalog/courses seems to no longer be working with Typesense. I suspect it was the upgrade to Typesense 2, but it could have been some other change.

The error seen is:

lms-1        | 2026-05-05 00:43:00,335 ERROR 104 [search.views] [user 4] [ip 192.168.65.1] views.py:233 - Search view exception when searching for None for user 4: InvalidParameter('Value None is not a string, integer, or boolean')
lms-1        | Traceback (most recent call last):
lms-1        |   File "/mnt/edx-search/search/views.py", line 201, in _course_discovery
lms-1        |     results = course_discovery_search(
lms-1        |               ^^^^^^^^^^^^^^^^^^^^^^^^
lms-1        |   File "/mnt/edx-search/search/api.py", line 159, in course_discovery_search
lms-1        |     results = searcher.search(
lms-1        |               ^^^^^^^^^^^^^^^^
lms-1        |   File "/mnt/edx-search/search/typesense.py", line 211, in search
lms-1        |     results = self.typesense_index.documents.search(search_args)
lms-1        |               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
lms-1        |   File "/openedx/venv/lib/python3.12/site-packages/typesense/sync/documents.py", line 340, in search
lms-1        |     stringified_search_params = stringify_search_params(search_parameters)
lms-1        |                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
lms-1        |   File "/openedx/venv/lib/python3.12/site-packages/typesense/preprocess.py", line 144, in stringify_search_params
lms-1        |     raise InvalidParameter(
lms-1        | typesense.exceptions.InvalidParameter: Value None is not a string, integer, or boolean
lms-1        | Internal Server Error: /search/unstable/v0/course_list_search/
lms-1        | 2026-05-05 00:43:00,338 ERROR 104 [django.request] [user None] [ip None] log.py:253 - Internal Server Error: /search/unstable/v0/course_list_search/

This PR applies a quick fix by using "" instead of None when we don't specify any particular search query.

I also updated the README.

Internal ref MNG-4952

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[samuelallan72]

@bradenmacdonald 👍

I haven't been able to test this yet, as my devstack is hanging on build... However it's a simple change and it looks solid to me.

Please see my inline comment about the readme update for consideration.

• I tested this: ...
• I read through the code
• I checked for accessibility issues
• Includes documentation

[samuelallan72]

It might be better to link to the official docs at https://docs.openedx.org/en/latest/site_ops/how-tos/use_typesense_search_backend.html as the source of truth. That doc has a complete explanation of enabling typesense, both with tutor-contrib-typesense and manually. It also has a more detailed listing of manual settings.

[bradenmacdonald]

Oh yeah, that's much better.

[feanil]

@bradenmacdonald thanks for the fix. Can you also bump the version for this so we can release it?

[bradenmacdonald]

@feanil Sure, done.

[feanil]

Publish going out here: https://github.com/openedx/edx-search/actions/runs/25517886603/job/74893859966