Firebase Cloud Firestore，如何使用javascript只接收4个文件？

// Import the functions you need from the SDKs you need
import { initializeApp } from "https://www.gstatic.com/firebasejs/9.6.1/firebase-app.js";
import { getFirestore, collection, query, orderBy, limit, getDocs } from "https://www.gstatic.com/firebasejs/9.6.1/firebase-firestore.js";

// Your web app's Firebase configuration
const firebaseConfig = {
  apiKey: "YOUR_API_KEY",
  authDomain: "YOUR_AUTH_DOMAIN",
  projectId: "YOUR_PROJECT_ID",
  storageBucket: "YOUR_STORAGE_BUCKET",
  messagingSenderId: "YOUR_MESSAGING_SENDER_ID",
  appId: "YOUR_APP_ID"
};

// Initialize Firebase
const app = initializeApp(firebaseConfig);
const db = getFirestore(app);

// Create a query to get the most recent 4 files
const q = query(collection(db, "files"), orderBy("createdAt", "desc"), limit(4));

// Get the documents in the query
getDocs(q).then((querySnapshot) => {
  querySnapshot.forEach((doc) => {
    console.log(`${doc.id} => ${JSON.stringify(doc.data())}`);
  });
}).catch((error) => {
  console.error("Error fetching documents: ", error);
});