python data_error ai_generated true

fastapi.exceptions.RequestValidationError: 1 validation error for Request body -> name field required (type=value_error.missing)

ID: python/fastapi-request-validation-field-required

Also available as: JSON · Markdown · 中文
80%Fix Rate
88%Confidence
0Evidence
2024-07-30First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
3.x active — — —

Root Cause

The Pydantic model declares a required field but the client JSON omits it, or the field name casing differs.

generic

中文

Pydantic 模型声明了必填字段，但客户端 JSON 中缺失，或字段名大小写不一致。

Workarounds

  1. 90% success 
    Give the field a default or make it optional:
class Item(BaseModel):
    name: str = ''
  2. 85% success 
    Fix the client payload to include the key with correct casing.

Dead Ends

Common approaches that don't work:

  1. 75% fail

    Swallows invalid input; the handler receives no valid data and downstream code fails.

  2. 80% fail

    extra controls unknown fields, not missing required ones.