Update project 3 iteration feat: core booking pipeline, webhook and async pdf worker CORE COPLETE

backend/api/routers/webhooks.py

@@ -0,0 +1,43 @@
+from fastapi import APIRouter, Depends, HTTPException, status
+from sqlalchemy import select
+from sqlalchemy.ext.asyncio import AsyncSession
+
+from core.rabbitmq import publish_ticket_paid_event
+from database.models import Ticket, TicketStatus
+from database.session import get_db
+from schemas.payment import PaymentWebhookRequest
+
+router = APIRouter(prefix="/api/webhooks", tags=["webhooks"])
+
+
+@router.post("/payment", status_code=status.HTTP_200_OK)
+async def payment_webhook(
+    body: PaymentWebhookRequest,
+    db: AsyncSession = Depends(get_db),
+) -> dict[str, str]:
+    result = await db.execute(select(Ticket).where(Ticket.id == body.ticket_id))
+    ticket: Ticket | None = result.scalar_one_or_none()
+
+    if ticket is None:
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail=f"Ticket {body.ticket_id} not found",
+        )
+
+    # Idempotency guard: повторный запрос с тем же ключом — возвращаем 200 без действий
+    if ticket.idempotency_key == body.idempotency_key:
+        return {"detail": "Already processed"}
+
+    if ticket.status != TicketStatus.LOCKED:
+        raise HTTPException(
+            status_code=status.HTTP_400_BAD_REQUEST,
+            detail=f"Ticket is in '{ticket.status}' state, expected 'LOCKED'",
+        )
+
+    ticket.status = TicketStatus.PAID
+    ticket.idempotency_key = body.idempotency_key
+    await db.commit()
+
+    await publish_ticket_paid_event(ticket_id=ticket.id, user_id=ticket.user_id or 0)
+
+    return {"detail": "Payment processed"}