data_collection.py

import firebase_admin
from firebase_admin import credentials
from firebase_admin import firestore
import json
import os


class DataService:
    instance = None

    def __init__(self):
        self.running_locally = False
        # Use a service account
        try:
            cred_object = json.loads(
                os.getenv('GOOGLE_APPLICATION_CREDENTIALS'))
        except:
            print(
                "Please set GOOGLE_APPLICATION_CREDENTIALS environmental variable. See readme for more info"
            )
            return

        cred = credentials.Certificate(cred_object)
        firebase_admin.initialize_app(cred)

        # only store code written on live heroku
        if "SHOULD_WRITE_TO_DATABASE" not in os.environ:
            self.running_locally = True

        self.db = firestore.client()

    @staticmethod
    def getInstance():
        if DataService.instance:
            return DataService.instance
        else:
            DataService.instance = DataService()
            return DataService.instance

    def writeQuery(self, input_code, output_code, input_lang, output_lang):
        if self.running_locally:
            return

        doc_ref = self.db.collection(u'user-query').document()
        doc_ref.set({
            u'input_code': input_code,
            u'output_code': output_code,
            u'input_lang': input_lang,
            u'output_lang': output_lang
        })