python data_error ai_generated true

pydantic.error_wrappers.ValidationError: 1 validation error for Item name field required (type=value_error.missing)

ID: python/fastapi-pydantic-validation-error

Also available as: JSON · Markdown · 中文
80%Fix Rate
85%Confidence
0Evidence
2025-01-25First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
3.x active — — —

Root Cause

A Pydantic model field is required but not provided in the request.

generic

中文

Pydantic 模型字段是必填的，但请求中未提供。

Workarounds

  1. 95% success Include all required fields in the request body 
    curl -X POST http://localhost:8000/items -H 'Content-Type: application/json' -d '{"name": "item"}'
  2. 90% success Make the field optional with a default 
    class Item(BaseModel):
    name: str = 'default'

Dead Ends

Common approaches that don't work:

  1. Sending the field with a null value 80% fail

    Null is not the same as a missing field; validation still fails.

  2. Using the wrong field name 90% fail

    Field names must match exactly.