rate_limit & limit¶

fastlimit.rate_limit ¶

rate_limit(default: str | RateLimitRule | None = None, *, ip: str | None = None, user: str | None = None, cost: int = 1, name: str | None = None) -> Any

Create a FastAPI dependency that enforces a rate limit.

The resolved rule is evaluated at request time — the limiter is looked up from app.state.

Parameters:

Name	Type	Description	Default
`default`	`str \| RateLimitRule \| None`	a rate string (`"10/min"`) for IP-only limiting. Acts as shorthand for `ip=`. Cannot be combined with `ip`.	`None`
`ip`	`str \| None`	Rate string for the IP bucket. e.g. `"10/min"`.	`None`
`user`	`str \| None`	Rate string for the authenticated-user bucket. e.g. `"50/min"`.	`None`
`cost`	`int`	Request cost. Useful for expensive endpoints. Default `1`.	`1`
`name`	`str \| None`	Optional stable name for Redis key prefix.	`None`

Returns:

Type	Description
`Any`	A `fastapi.Depends` object to use in `dependencies=[...]`.

Examples::

# IP-only shorthand
dependencies=[rate_limit("10/min")]

# Explicit IP
dependencies=[rate_limit(ip="10/min")]

# Dual bucket
dependencies=[rate_limit(ip="10/min", user="50/min")]

# Pre-built rule
dependencies=[rate_limit(Rules.LOGIN)]

# Inline on a router
router = APIRouter(dependencies=[rate_limit("200/min")])

Raises:

Type	Description
`FastLimitNotInitialized`	At request time if `limiter.init_app(app)` was never called.
`RateLimitExceeded`	At request time if the limit is exceeded.

fastlimit.limit ¶

limit(default: str | RateLimitRule | None = None, *, ip: str | None = None, user: str | None = None, cost: int = 1, name: str | None = None) -> Callable[[Any], Any]

Decorator that adds a rate limit to a FastAPI route.

Identical arguments to fastlimit.depends.rate_limit. The route function does not need Request in its signature.

Parameters:

Name	Type	Description	Default
`default`	`str \| RateLimitRule \| None`	IP-only rate string.	`None`
`ip`	`str \| None`	Rate string for IP bucket.	`None`
`user`	`str \| None`	Rate string for user bucket.	`None`
`cost`	`int`	Request cost per call.	`1`
`name`	`str \| None`	Stable Redis key name.	`None`

Returns:

Type	Description
`Callable[[Any], Any]`	A decorator that injects the rate limit as a hidden FastAPI dependency.

Examples::

from fastlimit import limit

@router.get("/photos")
@limit("20/min")
async def list_photos(): ...

@router.post("/upload")
@limit(ip="5/min", user="30/min")
async def upload(): ...

# Stacking: each @limit adds an independent bucket
@router.get("/feed")
@limit("200/min")
@limit(user="1000/min")
async def feed(): ...