fix: Document object dict #8251

[jlonge4]

Related Issues

• Fixes #8251

Proposed Changes:

This PR addresses the TypeError that occurs when trying to insert DocX converted document objects into PGVector or when using json.dumps() on docs.to_dict() output. The issue is caused by datetime objects not being JSON serializable.

Changes made:

• Modified the to_dict() method in the Document class to handle datetime serialization.
• Implemented a custom JSON encoder to convert datetime objects to ISO format strings during serialization.
• Updated the from_dict() method to properly deserialize the ISO format strings back to datetime objects.

How did you test it?

• Verified that json.dumps() works correctly on the output of docs.to_dict() from DocXToDocument Converter.

Notes for the reviewer

My thoughts are to fix this in a two PR effort. This being the first and a separate PR in haystack-core-integrations to address the problem there. Potentially the default_to_dict() function.

Checklist

• [x] I have read the contributors guidelines and the code of conduct
• [x] I have updated the related issue with new insights and changes
• [x] I added unit tests and updated the docstrings
• [x] I've used one of the conventional commit types for my PR title: fix:, feat:, build:, chore:, ci:, docs:, style:, refactor:, perf:, test:.
• [x] I documented my code
• [x] I ran pre-commit hooks and fixed any issue

[jlonge4]

@anakin87 There may be an entirely more efficient way of doing this as well

[julian-risch]

@jlonge4 Thank you for opening this pull request! @anakin87 May I ask you to take over this review please?