I'm using Firebase for my mobile app's entire backend and I was wondering which of the two is a more reliable way of performing the task of creating a user and then a batch of documents.

1. Create the Firebase user (using Firebase Auth) on the client and if it succeeds then perform a Firestore batch write also on the client to create the documents.
2. Call a Firebase cloud function from the client to perform the above task.

My reliability concern has to do with the network. If the user is created on the client but is unable to create the documents then, well, that's not good. But if the client is able to invoke a cloud function then I feel like network reliability is not an issue in the cloud environment. If the task is to fail in the cloud it will be because of violating an error that I have control over (i.e. bad email format, weak password). Which of the two is more reliable for my purposes?

CodePudding user response：

I definitely would recommend using option 1. You should create a user with Firebase Auth and then create a collection called "users" and add a document with the user's UID, which is auto generated. This should occur after you insure that there is no error in the Firebase Auth process. If there is you should just display the error. If you need more specific info, feel free to respond.

CodePudding user response：

If the user has a spotty connection, the call to the Cloud Functions is just as likely to fail as the call that writes them directly to Firestore. The main difference is that the Firestore SDKs will automatically retry the write operation in such cases, while with a Cloud Function you'd have to implement that yourself.