> ## Documentation Index
> Fetch the complete documentation index at: https://docs.neuraltrust.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Python middleware

> TrustGuard on the request path in FastAPI (same client for Django / Flask).

Middleware covers **input**. Guard completions in the route with `direction="output"`
([Python SDK](/trustguard/integrations/application/python-sdk)).

```python theme={null}
import json

from fastapi import FastAPI, Request
from starlette.responses import JSONResponse
from trustguard import AsyncTrustGuard

app = FastAPI()
client = AsyncTrustGuard("<your-trustguard-url>", api_key="<collector-api-key>")

@app.middleware("http")
async def trustguard_middleware(request: Request, call_next):
    if request.method == "POST":
        body = await request.body()
        response = await client.guard(
            {"input": body.decode()},
            direction="input",
            consumer_id=request.headers.get("x-user-id", ""),
            session_id=request.cookies.get("session_id", ""),
        )
        if response.is_blocked:
            return JSONResponse({"detail": "Blocked by TrustGuard"}, status_code=403)
        if response.transformed_payload:
            request._body = json.dumps(response.transformed_payload).encode()
    return await call_next(request)
```