Trending API error

[seabelis]

Problem

https://openlibrary.org/trending/daily.json throws the following error: A Problem Occurred We're sorry, a problem occurred while responding to your request:

    <class 'TypeError'>
    Object of type set is not JSON serializable

The reference code 2025-05-25/112433965649 has been created to track this error and we will investigate as we're able.

Reproducing the bug

1. Go to ... https://openlibrary.org/trending/daily.json
2. Do ...

• Expected behavior: no error
• Actual behavior: error message

Context

• Browser (Chrome, Safari, Firefox, etc):
• OS (Windows, Mac, etc):
• Logged in (Y/N):
• Environment (prod, dev, local): prod

Breakdown

Requirements Checklist

• [ ]

Related files

Stakeholders

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[emggeorge]

@mekarpeles @seabelis I got curious and have been looking into this issue this morning. I have a few ideas as to what's going on. My current guess is that the "json.dumps(result)" in the trending_books_api class in api.py isn't able to return what it is meant to, and so no json with the information is being returned. Possibly an issue with the input parameters, but again, I'm still investigating.

If no one else is currently working on this, I can submit a pull request later today with an idea on how to fix this.

[Ashkan-san]

This is still failing, could this be fixed please?

[mekarpeles]

Sentry reports: https://sentry.archive.org/organizations/ia-ux/issues/550406/?project=7&query=is%3Aunresolved%20issue.priority%3A%5Bhigh%2C%20medium%5D&referrer=issue-stream&stream_index=21

The https://openlibrary.org/trending/daily.json weekly.json and monthly.json all fail with the same error:

TypeError: Object of type set is not JSON serializable

on

openlibrary/plugins/openlibrary/api.py in GET at line 102
In App

        result = {
            'query': f"/trending/{period}",
            'works': [dict(work) for work in works],
            'days': days,
            'hours': i.hours,
        }
        return delegate.RawText(json.dumps(result), content_type="application/json")

With a stack trace of:

SINCE_DAYS = {'daily': 1, 'forever': None, 'monthly': 30, 'now': 0, 'weekly': 7, 'yearly': 365}
result = {'days': 1, 'hours': 0, 'query': '/trending/daily', 'works': [{...}, ...]

This is likely because either works contains a set field that is not serializable -- this seems to match this PR https://github.com/internetarchive/openlibrary/pull/10882/files by @emggeorge 🎉

[tfmorris]

The fact that this went undetected probably indicates that test coverage needs to be improved in addition to fixing the bug.

[mekarpeles]

We may want to replace this API with the trending feed from solr rather than a db query powered by reading log counts. Also, tests probably useful

[cdrini]

Fixed by #10882