Flask AttributeError: module 'flask.json' has no attribute 'JSONEncoder'
on channel: Hey Insights
Flask AttributeError: module 'flask.json' has no attribute 'JSONEncoder'
The `AttributeError: module 'flask.json' has no attribute 'JSONEncoder'` typically arises when code attempts to directly import `JSONEncoder` from `flask.json`, like `from flask.json import JSONEncoder`. This import path was valid in older Flask versions (pre-2.x). In Flask 2.0 and later, Flask's internal JSON handling was refactored, and `JSONEncoder` (along with `JSONDecoder`) is no longer directly exposed at the top level of the `flask.json` module. Instead, Flask 2.x introduced a JSON provider system, with the default provider accessible via `flask.json.provider.DefaultJSONProvider`. If you need to implement a custom JSON encoder, the recommended approach is to subclass Python's standard `json.JSONEncoder` and then integrate it into your Flask application by either setting `app.json_provider_class` to a custom provider that utilizes your encoder, or by directly assigning your encoder to `app.json.provider.json_encoder`. For merely accessing the default encoder, it's available through `current_app.json.provider.json_encoder`.
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Video link: • Flask AttributeError: module 'flask.json' ...
Channel link: / @heyinsights
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