Routing API — JustAPI Docs

Method Decorators

Each HTTP method decorator registers a route handler in the radix-trie router.

`@app.get()`

@app.get(
    path: str,
    dependencies: list[Depends] | None = None,
    middlewares: list[Callable] | None = None,
    tags: list[str] | None = None,
    summary: str | None = None,
    description: str | None = None,
    deprecated: bool = False,
    status_code: int | None = None,
    responses: dict | None = None,
    operation_id: str | None = None,
    openapi_extra: dict | None = None,
    name: str | None = None,
    include_in_schema: bool = True,
    native: bool = False,
)

`@app.post()`

@app.post(
    path: str,
    body_schema: type[Schema] | None = None,
    schema: type[Schema] | None = None,
    dependencies: list[Depends] | None = None,
    middlewares: list[Callable] | None = None,
    tags: list[str] | None = None,
    summary: str | None = None,
    description: str | None = None,
    deprecated: bool = False,
    status_code: int | None = None,
    responses: dict | None = None,
    operation_id: str | None = None,
    openapi_extra: dict | None = None,
    name: str | None = None,
    include_in_schema: bool = True,
    native: bool = False,
)

`@app.put()`, `@app.patch()`

Same signature as @app.post().

`@app.delete()`, `@app.head()`, `@app.options()`, `@app.trace()`

@app.delete(
    path: str,
    dependencies: list[Depends] | None = None,
    ...
)

`@app.websocket()`

@app.websocket(path: str)

`@app.sse()`

@app.sse(path: str)

`@app.route()`

@app.route("/items", methods=["GET", "POST"])
def items(request):
    if request.method == "GET":
        return list_items()
    return create_item(request)

Programmatic Route Registration

def read_item(request, item_id: int):
    return {"item_id": item_id}

app.add_api_route("/items/{item_id}", read_item, methods=["GET"])
app.add_api_websocket_route("/ws", my_ws_handler)

Route Parameters

Parameter	Applies To	Type	Description
`path`	All	`str`	URL pattern with `{param}` placeholders
`body_schema`	POST, PUT, PATCH	`Schema` subclass	Validate body against this schema in Rust
`dependencies`	All	`list[Depends]`	Route-level dependency injection
`middlewares`	All	`list[Callable]`	Route-level middleware functions
`tags`	All	`list[str]`	OpenAPI operation tags
`summary`	All	`str`	OpenAPI operation summary
`description`	All	`str`	OpenAPI operation description
`deprecated`	All	`bool`	Mark deprecated in OpenAPI
`status_code`	All	`int`	Default response status code
`responses`	All	`dict`	Additional OpenAPI responses
`operation_id`	All	`str`	OpenAPI operation ID
`openapi_extra`	All	`dict`	Extra OpenAPI metadata
`include_in_schema`	All	`bool`	Exclude from OpenAPI schema
`name`	All	`str`	Name for `url_for()`
`native`	POST, PUT, PATCH	`bool`	Execute entirely in Rust (724k+ RPS)

Path Parameter Types

Type	Example	Valid Input
`str`	`/hello/{name}`	Any string
`int`	`/items/{id}`	`42`
`float`	`/price/{val}`	`19.99`
`bool`	`/flag/{val}`	`true`, `1`, `yes`
`UUID`	`/users/{uid}`	`550e8400-...`
`datetime`	`/events/{ts}`	`2026-07-24T12:00:00Z`

Named Routes & URL Building

Use the name parameter and url_for() to build URLs:

@app.get("/items/{item_id}", name="get_item")
def read_item(request, item_id: int):
    ...

# Later: app.url_for("get_item", item_id=42) -> "/items/42"

Native Fast Path

When native=True, the handler validates the body and serializes the response entirely in Rust — zero GIL acquisition:

@app.post("/fast-items", body_schema=ItemSchema, native=True)
def create_item(request):
    return {"status": "ok"}

Route Resolution

Routes are resolved in O(1) time using a radix-trie (matchit). The route-lookup cache memoizes repeated lookups for the same path.

OpenAPI Generation

All registered routes automatically generate OpenAPI 3.1 documentation:

URL	Description
`/docs`	Swagger UI
`/redoc`	ReDoc
`/scalar`	Scalar API Reference
`/openapi.json`	Raw OpenAPI 3.1 spec

Method Decorators

@app.get()

@app.post()

@app.put(), @app.patch()

@app.delete(), @app.head(), @app.options(), @app.trace()

@app.websocket()

@app.sse()

@app.route()