FastAPI / update detail

0.149.0

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FastAPI·Oct 19, 2026, 05:21 PMChangeMay break your integrationAI-assisted summary

Summary

FastAPI now treats empty scalar form values as missing in form models, aligning with individual Form parameters.
Required fields missing in form data now raise validation errors; defaults are applied and remain unset in model dumps.
Empty strings in lists are preserved and omitted boolean fields default to False.

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Official source Last checked Oct 20, 2026, 7:01 PM

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AI-assisted summarysource healthyLast checked Oct 20, 2026, 7:01 PM

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