I am trying to build a program that should be able to update entries in a Firebase database. It should have a method that handles updating a single top-level node, and a method that handles updating all top-level nodes (max # of top-level nodes is 10). The data that I am inserting into the firebase database comes from an online API.

I am pretty new to node.js and javascript and I believe I have gotten myself caught in a mess of async, awaits, and promises, that I presumably don't understand fully yet.

This is my Firebase manager class:

import { initializeApp } from "firebase/app";
import { getDatabase, ref, remove, set, onValue } from "firebase/database";
import { ApiManager } from './api_manager.js'; // Fetching data from API here works as intended AFAIK
import { idList } from '../data/data.js';
import { DateManager } from "./date_manager.js";

export class FirebaseManager {
    constructor() {
        this.firebaseConfig = {
            ...
        };
        this.app = initializeApp(this.firebaseConfig);
        this.db = getDatabase();
    }

    /* Only update data for a single day (minimizing API calls) */
    async updateSingle(day, apiManager) {
        idList.forEach(async id => {
            let reference = ref(this.db, `${day}/${id}`);
            let data = await apiManager.getDataApi(day, id, apiManager.season);
            set(reference, data);
        });

        return;
    }

    /* Update and insert match info for the next 7 days
    nested by date in firebase RT database */
    async updateAll(datesArr, apiManager) {
        datesArr.forEach(async date => {
            await updateSingle(date, apiManager);
        });

        return;
    }

    /* Remove date child if it is in the past (e.g. not in the date array) */
    removeOldData(datesArr) {
        let rootRef = ref(this.db, "/");
        let foundOldDates = false;

        onValue(rootRef, (snapshot) => {
            snapshot.forEach(date => {
                if(!datesArr.includes(date.key)) {
                    let refOld = ref(this.db, `${date.key}/`);
                    remove(refOld)
                    foundOldDates = true;
                }
            })
        }, {
        onlyOnce: true
        });

        return foundOldDates;
    }
}

Now, based on the updateAll()- and updateSingle()-methods, I would like to every 3 minutes update my database from a seperate .js file. I do this here:

import { FirebaseManager } from "./firebase_manager.js";
import { ApiManager } from './api_manager.js';
import { DateManager } from './date_manager.js';

async function main() {

    // initialize managers
    let apiManager = new ApiManager();
    let dateManager = new DateManager();
    let firebaseManager = new FirebaseManager();

    await apiManager.getCurrentSeason();
    await firebaseManager.updateAll(dateManager.dates, apiManager); // Error on FirebaseManager's updateSingle() happens here

    let countDaily = 0;
    let dateRemoved = false;

    while(true) {
        // update dates in class
        dateManager.update(); 

        // update season in class once every 24 hrs 
        // countDaily increments every 4 min. 1440 min in a day. 1440 / 4 = 360
        if(countDaily >= 360) {
            await apiManager.getCurrentSeason();
            countDaily = 0; 
        }

        // update info for today
        await firebaseManager.updateSingle(
            dateManager.getToday(),
            apiManager);

        // remove old date, and if something is removed update/add info for all days
        dateRemoved = firebaseManager.removeOldData(dateManager.dates);
        if(dateRemoved) {
            await firebaseManager.updateAll(
                dateManager.dates, 
                apiManager);
            dateRemoved = false;
        }

        // increment
        countDaily  ;

        // sleep 3 minutes
        // (max # of requests / # of requests required to update single day)
        await new Promise(r => setTimeout(r, 240000)); 
    }
}

main();

Running this gives me the following error:

ReferenceError: updateSingle is not defined
    at file:///c:/Users/x/Projects/backend/src/firebase_manager.js:37:13
    at Array.forEach (<anonymous>)
    at FirebaseManager.updateAll (file:///c:/Users/x/Projects/backend/src/firebase_manager.js:36:18)
    at main (file:///c:/Users/x/Projects/backend/src/app.js:25:31)
    at processTicksAndRejections (node:internal/process/task_queues:96:5)

I have tried adding and removing async/await several places but to no avail. The logic of writing to my Firebase database works, as I can do without using my updateSingle()-method, so I am unsure what I am missing. All help and pointers in the right direction are appreciated.

CodePudding user response：

try with await this.updateSingle() inside your FirebaseManager.updateAll() method.