[firefly-cpp]

Problem

The API's own errors are JSON ({"message": ...}), but errors raised by Flask itself were returned as HTML error pages:

Request	Before	After
Invalid or empty JSON body	400, HTML	400 {"message": "Invalid JSON: the request body could not be parsed."}
Unknown path	404, HTML	404 {"message": "Not Found."}
Wrong method (e.g. DELETE /measure)	405, HTML	405 {"message": "Method Not Allowed."}, Allow header kept
Unexpected error in the server	500, HTML	500 {"message": "Internal server error."}, logged with traceback
Payload too large	413, JSON	unchanged
GET / (index page)	200, HTML	unchanged

Changes

• SucculentAPI.http_error() handles every HTTPException and returns it as JSON. Werkzeug's generic descriptions are replaced with the short error name (e.g. Not Found.); specific descriptions are kept. Response headers are kept.
• SucculentRequest (set as the app's request class) raises a BadRequest with a clear message when a JSON body cannot be parsed.
• SucculentAPI.internal_error() handles unexpected exceptions: it logs the traceback and returns a generic JSON 500 without exposing details to the client.
• README and getting started mention that all errors are JSON with a message field.

Tests

• New TestJsonErrors (invalid/empty JSON, 404, 405 with Allow, unexpected error logged and hidden, existing 413 unchanged, index still HTML). Five of them fail on the previous code.
• Full suite: 51 passed.

Compatibility

Status codes are unchanged; only the body and content type of these error responses change from HTML to JSON.

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Generated by Claude Code