Sample: Script to export Firestore collection as CSV

firestore2csv.py

"""Script to export Firestore collection as CSV."""

import csv
import sys
from pathlib import Path

from firebase_admin import credentials, firestore, initialize_app

CRED_FILE = Path(__file__).resolve().parent / 'firebase-privateKey.json'
COLLECTION_NAME = 'XXX'
FIELDS = ['name', 'body', 'created']
DIRECTION = firestore.Query.DESCENDING


def main():
    """Main function"""
    client = firebase_client(str(CRED_FILE))
    collection = client.collection(COLLECTION_NAME)

    writer = csv_writer(sys.stdout, FIELDS)
    writer.writeheader()
    for snapshot in collection.order_by('created', direction=DIRECTION).get():
        data = snapshot.to_dict()
        writer.writerow(data)


def firebase_client(cred_file):
    """Generate Firebase client"""
    cred = credentials.Certificate(cred_file)
    app = initialize_app(credential=cred)
    client = firestore.client(app=app)
    return client


def csv_writer(file, fields):
    """Generate CSV writer"""
    return csv.DictWriter(file, fields)


if __name__ == '__main__':
    main()