使用云函数执行Firestore操作更安全吗

要在Firestore中添加/更新/删除记录，我可以在执行此操作的应用程序中运行代码，也可以调用处理此操作的云函数。是"；"更安全"；让我的应用程序以云功能的方式实现它？这种方式需要更长的时间，但我担心Firebase会以某种方式变得脆弱。我曾经读到，为了制作一个真正安全的应用程序，你应该假设某个恶意用户已经对你的应用程序进行了逆向工程。我应该假设对Firestore的所有更改使用云函数是最安全的途径吗？还是没有区别？

使用客户端的代码：

CollectionReference users = FirebaseFirestore.instance.collection('users');
Future<void> addUser() {
// Call the user's CollectionReference to add a new user
return users
.add({
'full_name': fullName, // John Doe
'company': company, // Stokes and Sons
'age': age // 42
})
.then((value) => print("User Added"))
.catchError((error) => print("Failed to add user: $error"));
}

使用云功能：

exports.createUser = functions.https.onCall(async (data, context) => {
const uid = context?.auth?.uid
if (!uid) {
return {result: 0, message: 'You are not authorized.'}
}
const username = data.user
const email = data.email  
var result: number 
var message: string 
//Check to see if that username already exists
const doesUserExist = await TS_doesUserExist(username)
const createUser = await TS_createUser(uid, username, email)
if (doesUserExist[0] == 0) {
if (createUser[0] == 1) {
result = 1
message = ''
} else {
result = 0
message = createUser[1]
}
} else {
result = 0
message = doesUserExist[1]
}
return {result: result, message: message}
})
async function TS_createUser(uid: string, username: string, email: string): Promise<[number, string]> {
var result: number = 0
var message: string = ''
//Create SECURE_userinfo doc
const userInfoDoc = await admin.firestore()
.collection(usersCollPath)
.doc(uid)  // use uid as document ID
.collection(secureUserInfoCollPath)
.doc()
.set({
createDate: admin.firestore.FieldValue.serverTimestamp(), //signupdate
email: email,
})
//Create stat doc  
const statDoc = await admin.firestore()
.collection(usersCollPath)
.doc(uid)
.collection(statCollPath)
.doc()
.set({
stat: 1,
})
//Create username doc
const usernameDoc = await admin.firestore()
.collection(usersCollPath)
.doc(uid)
.collection(usernameCollPath)
.doc()
.set({
username: username,
})
if (userInfoDoc) {
if (statDoc) {
if (usernameDoc) {
result = 1
message = ''
} else {
result = 0
message = 'Could not create username doc'
}
} else {
result = 0
message = 'Could not create status doc'
}
} else {
result = 0
message = 'Could not create user info doc'
}  
return [result, message]
}