varbees-rateguard 0.1.0

Python middleware SDK for RateGuard

RateGuard Python SDK

RateGuard is a middleware-first API protection and observability SDK for Python apps.

It runs entirely in-process by default:

• rate limiting
• token budgets
• circuit breaking
• request events

No external service is required for standalone use. Configure an event endpoint only when you want RateGuard events delivered outside the process.

Install

pip install varbees-rateguard

Quick Start

from rateguard import BudgetExceeded, RateGuard

rg = RateGuard(preset="standard")
budget = rg.budget


async def call_provider(user_id: str) -> None:
    try:
        async with budget.enforce(user_id=user_id, hard_stop=True):
            # Call your LLM, API, worker, or provider here.
            pass

        budget.record(user_id=user_id, tokens=1200)
    except BudgetExceeded as exc:
        print(exc)
        raise

For provider SDKs that return token usage, enforce before the request and record the returned usage afterward:

async with rg.budget.enforce(user_id="me", hard_stop=True):
    response = await client.chat.completions.create(model="gpt-4o", messages=messages)
    rg.budget.record(user_id="me", tokens=response.usage.total_tokens)

FastAPI

from fastapi import Depends, FastAPI, Request
from rateguard import RateGuard

app = FastAPI()
rg = RateGuard(preset="standard")
app.add_middleware(rg.asgi_middleware)


@app.post("/chat")
async def chat(req: Request, _=Depends(rg.require)):
    return {"ok": True}

Flask / WSGI

from flask import Flask
from rateguard import RateGuard, RateGuardMiddleware

app = Flask(__name__)
rg = RateGuard(preset="standard")
app.wsgi_app = RateGuardMiddleware(app.wsgi_app, guard=rg.runtime)

Configuration

Key	Type	Default
preset	dev / standard / high-throughput / llm-heavy / strict-upstream-protection	dev
hard_stop	bool	True
monthly_limit	int	preset-derived
soft_stop_at	float	0.8

Docs

• Go SDK: packages/sdk-go
• Node SDK: packages/sdk-node