Litestar library documentation#

Litestar is a powerful, flexible, highly performant, and opinionated ASGI framework.

The Litestar framework supports Plugins, ships with dependency injection, security primitives, OpenAPI schema generation, MessagePack, middlewares, a great CLI experience, and much more.

Installation#

pip install litestar

Tip

litestar[standard] includes commonly used extras like uvicorn and jinja2 (for templating).

Extras
Pydantic

pip install litestar[pydantic]

Attrs

pip install litestar[attrs]

Brotli Compression Middleware:

pip install litestar[brotli]

Cookie Based Sessions

pip install litestar[cryptography]

JWT

pip install litestar[jwt]

RedisStore

pip install litestar[redis]

Picologging

pip install litestar[picologging]

StructLog

pip install litestar[structlog]

Prometheus Instrumentation

pip install litestar[prometheus]

Open Telemetry Instrumentation

pip install litestar[opentelemetry]

SQLAlchemy

pip install litestar[sqlalchemy]

CLI

Deprecated since version 2.1.1: The litestar base installation now includes the CLI dependencies and this group is no longer required to use the CLI. If you need the optional CLI dependencies, install the standard group instead. Will be removed in 3.0

pip install litestar[cli]

Jinja Templating

pip install litestar[jinja]

Mako Templating

pip install litestar[mako]

Standard Installation (includes Uvicorn and Jinja2 templating):

pip install litestar[standard]

All Extras:

pip install litestar[full]

Note

The full extras is not recommended because it will add a lot of unnecessary extras.

Minimal Example#

At a minimum, make sure you have installed litestar[standard], which includes uvicorn.

First, create a file named app.py with the following contents:

from litestar import Litestar, get


@get("/")
async def index() -> str:
    return "Hello, world!"


@get("/books/{book_id:int}")
async def get_book(book_id: int) -> dict[str, int]:
    return {"book_id": book_id}


app = Litestar([index, get_book])

Then, run the following command:

litestar run
# Or you can run Uvicorn directly:
uvicorn app:app --reload

You can now visit http://localhost:8000/ and http://localhost:8000/books/1 in your browser and you should see the responses of your two endpoints:

"Hello, world!"

and

{"book_id": 1}

Tip

You can also check out the automatically generated OpenAPI-based documentation at:

  • http://localhost:8000/schema (for ReDoc),

  • http://localhost:8000/schema/swagger (for Swagger UI),

  • http://localhost:8000/schema/elements (for Stoplight Elements)

  • http://localhost:8000/schema/rapidoc (for RapiDoc)

You can check out a more in-depth tutorial in the Developing a basic TODO application section!

Sponsors#

Litestar is a community-driven open-source initiative that thrives on the generous contributions of our sponsors, enabling us to pursue innovative developments.

A huge thank you to our current sponsors:

Scalar.com

Scalar.com

Telemetry Sports

Telemetry Sports

Stok

Stok

We invite organizations and individuals to join our sponsorship program. By becoming a sponsor on platforms like GitHub and Open Collective, you can play a pivotal role in our project’s growth.

Additionally, we engage in pledge-based sponsorship opportunities through Polar.

Expanded Example#

Define your data model using pydantic or any library based on it (for example ormar, beanie, SQLModel):

from pydantic import BaseModel, UUID4


class User(BaseModel):
    first_name: str
    last_name: str
    id: UUID4

You can also use dataclasses (standard library and Pydantic), typing.TypedDict, or msgspec.Struct.

from uuid import UUID

from dataclasses import dataclass
from litestar.dto import DTOConfig, DataclassDTO


@dataclass
class User:
    first_name: str
    last_name: str
    id: UUID


class PartialUserDTO(DataclassDTO[User]):
    config = DTOConfig(exclude={"id"}, partial=True)

Define a Controller for your data model:

from typing import List

from litestar import Controller, get, post, put, patch, delete
from litestar.dto import DTOData
from pydantic import UUID4

from my_app.models import User, PartialUserDTO


class UserController(Controller):
    path = "/users"

    @post()
    async def create_user(self, data: User) -> User: ...

    @get()
    async def list_users(self) -> List[User]: ...

    @patch(path="/{user_id:uuid}", dto=PartialUserDTO)
    async def partial_update_user(
        self, user_id: UUID4, data: DTOData[User]
    ) -> User: ...

    @put(path="/{user_id:uuid}")
    async def update_user(self, user_id: UUID4, data: User) -> User: ...

    @get(path="/{user_id:uuid}")
    async def get_user(self, user_id: UUID4) -> User: ...

    @delete(path="/{user_id:uuid}")
    async def delete_user(self, user_id: UUID4) -> None: ...
from litestar import Controller, get, post, put, patch, delete
from litestar.dto import DTOData
from pydantic import UUID4

from my_app.models import User, PartialUserDTO


class UserController(Controller):
    path = "/users"

    @post()
    async def create_user(self, data: User) -> User: ...

    @get()
    async def list_users(self) -> list[User]: ...

    @patch(path="/{user_id:uuid}", dto=PartialUserDTO)
    async def partial_update_user(
        self, user_id: UUID4, data: DTOData[User]
    ) -> User: ...

    @put(path="/{user_id:uuid}")
    async def update_user(self, user_id: UUID4, data: User) -> User: ...

    @get(path="/{user_id:uuid}")
    async def get_user(self, user_id: UUID4) -> User: ...

    @delete(path="/{user_id:uuid}")
    async def delete_user(self, user_id: UUID4) -> None: ...

When instantiating your app, import your controller into your application’s entry-point and pass it to Litestar:

from litestar import Litestar

from my_app.controllers.user import UserController

app = Litestar(route_handlers=[UserController])

To run your application, use an ASGI server such as uvicorn :

uvicorn my_app.main:app --reload

Philosophy#

  • Litestar is a community-driven project. This means not a single author, but rather a core team of maintainers is leading the project, supported by a community of contributors. Litestar currently has 5 maintainers and is being very actively developed.

  • Litestar draws inspiration from NestJS - a contemporary TypeScript framework - which places opinions and patterns at its core.

  • While still allowing for function-based endpoints, Litestar seeks to build on Python’s powerful and versatile OOP, by placing class-based controllers at its core.

  • Litestar is not a microframework. Unlike frameworks such as FastAPI, Starlette, or Flask, Litestar includes a lot of functionalities out of the box needed for a typical modern web application, such as ORM integration, client- and server-side sessions, caching, OpenTelemetry integration, and many more. It’s not aiming to be “the next Django” (for example, it will never feature its own ORM), but its scope is not micro either.

Feature comparison with similar frameworks#

Litestar

FastAPI

Starlette

Sanic

Quart

OpenAPI

Automatic API documentation

Swagger, ReDoc, Stoplight Elements

Swagger, ReDoc

Data validation

Dependency Injection

Class based routing

(Through extension)

ORM integration

SQLAlchemy, Tortoise, Piccolo

(Through extension)

Templating

Jinja, Mako

Jinja

Jinja

Jinja

Jinja

MessagePack

CORS

(Through extension)

CSRF

Rate-limiting

(Through extension)

JWT

Sessions

Client-side

Client-side

Client-side

Authentication

JWT / Session based

Caching

Example Applications#

  • litestar-pg-redis-docker : In addition to Litestar, this demonstrates a pattern of application modularity, SQLAlchemy 2.0 ORM, Redis cache connectivity, and more. Like all Litestar projects, this application is open to contributions, big and small.

  • litestar-fullstack : A fully-capable, production-ready fullstack Litestar web application configured with best practices. It includes SQLAlchemy 2.0, VueJS, Vite, SAQ job queue, Jinja templates and more. Read more.

  • litestar-hello-world: A bare-minimum application setup. Great for testing and POC work.