feat: add FastAPI feedback backend

feedback-api/main.py

@@ -0,0 +1,70 @@
+import hashlib
+from contextlib import asynccontextmanager
+
+from fastapi import FastAPI, Request
+from fastapi.middleware.cors import CORSMiddleware
+from pydantic import BaseModel
+
+from database import add_feedback, check_rate_limit, get_stats, init_db
+
+
+class FeedbackIn(BaseModel):
+    url: str
+    choice: str
+    timestamp: str
+
+
+RATE_LIMIT = 5
+RATE_WINDOW = 3600
+
+
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+    await init_db()
+    yield
+
+
+app = FastAPI(lifespan=lifespan)
+
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=["*"],
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+
+def get_client_ip(request: Request) -> str:
+    cf_ip = request.headers.get("cf-connecting-ip")
+    if cf_ip:
+        return cf_ip
+    forwarded = request.headers.get("x-forwarded-for")
+    if forwarded:
+        return forwarded.split(",")[0].strip()
+    return request.client.host or "unknown"
+
+
+@app.post("/api/feedback")
+async def receive_feedback(body: FeedbackIn, request: Request):
+    ip = get_client_ip(request)
+    ip_hash = hashlib.sha256(ip.encode()).hexdigest()
+
+    if not await check_rate_limit(ip_hash, RATE_LIMIT, RATE_WINDOW):
+        await add_feedback(ip_hash, body.url, body.choice, body.timestamp)
+
+    return {"ok": True}
+
+
+@app.get("/api/feedback/stats")
+async def stats():
+    return await get_stats()
+
+
+@app.get("/api/feedback/health")
+async def health():
+    return {"status": "ok"}
+
+
+if __name__ == "__main__":
+    import uvicorn
+    uvicorn.run("main:app", host="0.0.0.0", port=8005)