_extract_form_body() — fastapi Function Reference

Architecture documentation for the _extract_form_body() function in utils.py from the fastapi codebase.

Function python DependencyInjection ParamFunctions calls 2 called by 1

Entity Profile

DependencyInjection→ ParamFunctions→ _extract_form_body() — fastapi Function Reference

Dependency Diagram

graph TD
  5ea666fe_6840_7f7c_f45d_e67adf31134b["_extract_form_body()"]
  9e602cbf_3139_86ae_5666_97b8806942de["utils.py"]
  5ea666fe_6840_7f7c_f45d_e67adf31134b -->|defined in| 9e602cbf_3139_86ae_5666_97b8806942de
  b8125a22_3ce8_c209_1d2b_1aaf5de6f8b2["request_body_to_args()"]
  b8125a22_3ce8_c209_1d2b_1aaf5de6f8b2 -->|calls| 5ea666fe_6840_7f7c_f45d_e67adf31134b
  cd9f411c_484c_7d25_1807_29f71d341257["_get_multidict_value()"]
  5ea666fe_6840_7f7c_f45d_e67adf31134b -->|calls| cd9f411c_484c_7d25_1807_29f71d341257
  0f3cd5cf_3aea_6cfe_477e_4813f1243d25["get_validation_alias()"]
  5ea666fe_6840_7f7c_f45d_e67adf31134b -->|calls| 0f3cd5cf_3aea_6cfe_477e_4813f1243d25
  style 5ea666fe_6840_7f7c_f45d_e67adf31134b fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

fastapi/dependencies/utils.py lines 882–918

async def _extract_form_body(
    body_fields: list[ModelField],
    received_body: FormData,
) -> dict[str, Any]:
    values = {}

    for field in body_fields:
        value = _get_multidict_value(field, received_body)
        field_info = field.field_info
        if (
            isinstance(field_info, params.File)
            and is_bytes_or_nonable_bytes_annotation(field.field_info.annotation)
            and isinstance(value, UploadFile)
        ):
            value = await value.read()
        elif (
            is_bytes_sequence_annotation(field.field_info.annotation)
            and isinstance(field_info, params.File)
            and value_is_sequence(value)
        ):
            # For types
            assert isinstance(value, sequence_types)
            results: list[Union[bytes, str]] = []
            for sub_value in value:
                results.append(await sub_value.read())
            value = serialize_sequence_value(field=field, value=results)
        if value is not None:
            values[get_validation_alias(field)] = value
    field_aliases = {get_validation_alias(field) for field in body_fields}
    for key in received_body.keys():
        if key not in field_aliases:
            param_values = received_body.getlist(key)
            if len(param_values) == 1:
                values[key] = param_values[0]
            else:
                values[key] = param_values
    return values