save firestore collections

dump.py

import os

import firebase_admin
from firebase_admin import credentials
from firebase_admin import firestore
cred = credentials.Certificate('../your_project_credential.json')
firebase_admin.initialize_app(cred, {
    'projectId': 'your_project_id'
})

db = firestore.client()
data = [{'uid': doc.id, 'name': doc.to_dict()['name']} for doc in db.collection('your_collection').stream()]
data = sorted(data, key=lambda x: x['name'], ensure_ascii=False)  # for multibyte
with open('data.json', 'w') as f:
    f.write(data)