extraction

module

Typed extraction of query parameters and form/JSON body data.

Automatically populates frozen dataclass instances from request data, converting string values to the annotated field types. Used by the handler resolution system when…

Typed extraction of query parameters and form/JSON body data.

Automatically populates frozen dataclass instances from request data, converting string values to the annotated field types. Used by the handler resolution system when a parameter's type annotation is a dataclass.

Resolution rules (by HTTP method):

GET / HEAD: extract from query string
POST / PUT / PATCH / DELETE: extract from form body or JSON body (based on Content-Type header)

Supported field types:str, int, float, bool. Missing keys use the dataclass field default. Type conversion failures also fall back to the default.

extraction

Name	Type	Default	Description
`type`		—
`qualified_name`		—
`element_type`		—
`description`		—
`source_file`		—
`line_number`		—
`is_autodoc`		—
`autodoc_element`		—
`_autodoc_template`		—
`_autodoc_url_path`		—
`_autodoc_page_type`		—
`title`		—
`doc_content_hash`		—

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function is_extractable_dataclass

Return True if annotation is a user-defined dataclass type.

Excludes chirp's own dataclass types (Request, Response, etc.) which should never be…

function extract_dataclass

Create a dataclass instance from a mapping (query params, form, JSON).

For each field in cls, looks up the field name in data…

function _convert

Convert value to target_type, returning value unchanged on failure.

Logs a WARNING when int/float coercion fails so the mismatch is visible.

function _resolve_type

Resolve common type names from string annotations.

is_extractable_dataclass

function

def is_extractable_dataclass(annotation: Any) -> bool

Return True if annotation is a user-defined dataclass type.

Excludes chirp's own dataclass types (Request, Response, etc.) which should never be auto-extracted from query/form data.

Parameters

Name	Type	Default	Description
`annotation`	`Any`	—

extract_dataclass

function

def extract_dataclass(cls: type[T], data: Mapping[str, Any]) -> T

Create a dataclass instance from a mapping (query params, form, JSON).

For each field in cls, looks up the field name in data. If found, converts the value to the field's annotated type. If missing or conversion fails, uses the field's default value.

Parameters

Name	Type	Default	Description
`cls`	`type[T]`	—	A dataclass type to instantiate.
`data`	`Mapping[str, Any]`	—	A mapping of string keys to values (query params, form data, or parsed JSON).

_convert

function

def _convert(value: Any, target_type: Any) -> Any

Convert value to target_type, returning value unchanged on failure.

Logs a WARNING when int/float coercion fails so the mismatch is visible.

Parameters

Name	Type	Default	Description
`value`	`Any`	—
`target_type`	`Any`	—

_resolve_type

function

def _resolve_type(name: str) -> type | str

Resolve common type names from string annotations.

Parameters

Name	Type	Default	Description
`name`	`str`	—

View source · /home/runner/work/chirp/chirp/site/../src/chirp/extraction.py:1