added JSONReader to file mappings

[denen99]

Description

The default_file_reader_cls dict that maps file extensions to the proper XReader, did not include a mapping for the new JSONreader. This PR adds the mapping for .json files to the JSONReader

Fixes # (issue)

New Package?

Did I fill in the tool.llamahub section in the pyproject.toml and provide a detailed README.md for my new integration or package?

• Yes
• [ x ] No

Version Bump?

Did I bump the version in the pyproject.toml file of the package I am updating? (Except for the llama-index-core package)

• Yes
• [ x ] No

Type of Change

Bugfix

Please delete options that are not relevant.

• [ x ] Bug fix (non-breaking change which fixes an issue)
• [ x ] This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• Added new unit/integration tests
• Added new notebook (that tests end-to-end)
• [ x ] I stared at the code and made sure it makes sense

Suggested Checklist:

• [ x ] I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added Google Colab support for the newly added notebooks.
• [ x ] My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• [ x ] New and existing unit tests pass locally with my changes
• [ x ] I ran make format; make lint to appease the lint gods

[nerdai]

Thanks @denen99. I've left a comment in my review. I don't think will be able to bring in the JSONReader in the way that you've got it currently.

[nerdai]

I think you may be using a legacy version of llama_index (i.e., v0.9.4x and earlier)?

JSONReader is available in our integration package call llama-index-readers-json which isn't included as a dependency in the umbrella llama-index package. Since we don't include that in that umbrella package, we don't try to import it here.