Sanic

Rate-limit middleware using client IP with Sanic's request middleware hook.

pip install sanic rate-limiter

Request Flow

sequenceDiagram
    participant C as Client
    participant M as rate_limit_middleware
    participant RL as RateLimiter
    participant H as Route Handler
    C->>M: HTTP Request
    M->>RL: allow(remote_addr)
    alt allowed
        RL-->>M: None
        M->>H: handler(request)
        H-->>M: response
        M-->>C: 200 OK
    else denied
        RL-->>M: false
        M-->>C: 429 Rate limit exceeded
    end

Code

from sanic import Sanic, json
from sanic.request import Request
from sanic.response import text

from rate_limiter import RateLimiter, TokenBucketStrategy

app = Sanic("RateLimitedApp")
limiter = RateLimiter(lambda: TokenBucketStrategy(capacity=10, rate=2))


@app.middleware("request")
async def rate_limit_middleware(request: Request):
    key = request.remote_addr or request.ip or "unknown"
    if not await limiter.allow(key):
        return text("Rate limit exceeded", status=429)


@app.get("/")
async def index(request: Request):
    return json({"message": "Hello, World!"})


if __name__ == "__main__":
    app.run(host="0.0.0.0", port=8080)

Sanic request middleware returns None to continue or a Response to short-circuit — returning the 429 response stops the request before it reaches the handler.

View Source on GitHub