flutter - How can I do automatic uid for docs in firebase?

Question

Im trying to do a group system for a flutter app and I need to store it in firebase, and every group has his own ID, it's called "groupID". How to do programmatically that every new group create has his "groupID" create automatically. Is organized like this:

In other words, how can I do in the code to fill the Groups column?

question from:https://stackoverflow.com/questions/65896166/how-can-i-do-automatic-uid-for-docs-in-firebase

Answer 1

In Flutter,

1. Let firestore creates document reference with it's automatic document ID

DocumentReference docRef = firestore.collection('Groups').document();
print(docRef.documentID);
docRef.setData({JSON Data});

2. Providing your own document ID for groups

String groupID = 'unique_id'
DocumentReference docRef = firestore.collection('Groups').document(groupID);
print(docRef.documentID);
docRef.setData({JSON Data});

For constraints on document ID - https://firebase.google.com/docs/firestore/quotas#collections_documents_and_fields