request-mapper 0.1.0

Map request data into pydantic models

Python request mapper

Map and validate incoming request data to Pydantic models. Request-mapper is framework agnostic with first-party support for Flask.

Examples

# Add this in your app initialization code.
setup_mapper(
    integration=FlaskIntegration(
        # Automatically decorate views to avoid adding @map_request to every view.
        # Will not incur any performance overhead for views that don't use request-mapper.
      
        # If map_views is enabled, setup_mapper must be called after 
        # all views have been registered!
        map_views=True,
        # Register an error handler that returns 422 alongside pydantic validation errors
        # when the request cannot be mapped.
        add_error_handler=True,
    )
)


# Define models using Pydantic v1 or v2.
class PostCreateRequest(BaseModel):
    title: str
    content: str


class PostFilterQuery(BaseModel):
    status: PostStatus | None = None


@app.get("/posts")
# Map data from the current request.
def post_list_all(query: FromQueryString[PostFilterQuery]) -> PaginatedResponse[Post]:
    # "query" is a valid pydantic model at this point.
    return PaginatedResponse(...)


@app.post("/posts")
def post_create(body: FromRequestBody[PostCreateRequest]) -> PostCreateResponse:
    # "body" is a valid pydantic model at this point.
    return PostCreateResponse(...)

Quickstart

• pip install request-mapper.
• In your application setup, call mapper.setup_mapper with the integration of your choice.
• Decorate targets with @map_request (Optional when using flask integration)
• Map request data using one of the provided annotated types
  • FromQueryString[T] or Annotated[T, QueryStringMapping()]
  • FromRequestBody[T] or Annotated[T, RequestBodyMapping()]
  • FromFormData[T] or Annotated[T, FormDataMapping()]

Integrations

Flask

• Pull data from flask's request args, json and form data.
• Optional: Automatically map views without having to decorate them.
  • Views which do not use request mapper will not incur any performance penalty.
  • When using this feature the call to setup_mapper must be AFTER all views are registered.
• Optional: Set up an error handler for validation errors which makes the api respond with a 422.

Custom integrations

You can create your own integration by inheriting BaseIntegration and supplying an instance of that to the setup_mapper call.

Note that you must decorate your views with @map_request