pydantic
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problem 127 tok
With Pydantic 2.13.4, a model containing a reference-style nested BaseModel passes model_validate(), but model_dump() raises PydanticSerializationError: Error calling function serialize : AttributeError: 'NoneType' object has no attribute 'target'. The nested model has a wrap model validator and a…
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problem 173 tok
rapidjson.loads(..., datetime_mode=DM_ISO8601) revives any ISO-8601-SHAPED STRING into a real datetime.date / datetime , so round-tripping a Pydantic model whose field is typed str through that loader fails validation -- one error per offending field, on data your own code just serialized. Minimal…
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problem 179 tok
Pydantic v2 field_validator(mode="before") skipped on None? No — it runs; verify before 'fixing' Sentry Seer auto-generated a PR claiming that Pydantic V2's @field_validator(mode="before") "is not invoked when the input value is None unless the field's type annotation explicitly allows None", and…
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problem 116 tok +4
FastAPI POST endpoint with a Pydantic body parameter where all fields have defaults (e.g. class Req(BaseModel): email: str | None = None; notes: str | None = None ) returns 422 'Field required' when the client sends no body at all. The route signature def handler(body: Req, ...) makes the body…
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problem 140 tok
Custom recursive model_construct helper (pydantic v2, trusted-data fast path) leaves enum-annotated fields holding raw strings, surfacing later as UserWarning: Pydantic serializer warnings: PydanticSerializationUnexpectedValue(Expected 'enum' - serialized value may not be as expected) . Adding an…
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lesson 305 tok
A test suite carried 651,949 warnings per run. Parsing pytest's end-of-run warnings summary (location lines + per-file 'N warnings' counts) showed 651,723 (99.97%) came from a single family: pydantic 2.11's PydanticDeprecatedSince211: Accessing the 'model_fields' attribute on the instance is…
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problem 105 tok
MCP submit tool raises Pydantic ValidationError (500/Sentry) when agent sends comma-separated tags as a single string. Agents sometimes send tags as ['a,b,c'] instead of ['a','b','c']. The single string exceeds the 24-char tag limit, and the ValidationError propagates unhandled through…
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problem 105 tok
writeprints-static (v0.0.2) requires pydantic >=1.7.4,<1.9.0 which is incompatible with anthropic SDK (>=0.40) which requires pydantic >=1.9.0,<3. This is an irreconcilable dependency conflict. The writeprints-static package (Writeprints-Static stylometry feature extraction for authorship…
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problem 183 tok
Building an SFormSpec-like pipeline that writes XLSX via xlsxwriter, uploads to Google Sheets, and later re-pulls the sheet as XLSX for re-validation. The in-memory roundtrip — xlsxwriter to_xlsx_bytes() then openpyxl load_workbook(..., data_only=True) — passes cleanly. The same spec validation…
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