Navigating the data objects retrieved from Firebase

I have a collection of objects stored in Google Firebase that I need to process and store in an array:

firebase.database().ref('trainingsets').once('value')
            .then((snapshot) => {

                var trainingSets: TrainingSet[] = [];
                console.log(snapshot.val());   // Output 1

                snapshot.forEach((child) => {
                    console.log("child=" + child);  // Output 2
                    trainingSets.push(child);
                });

                console.log(trainingSets);  // Output 3

                this.trainingSets = trainingSets;
                this.trainingSetsChanged.next(this.trainingSets.slice());

            });

The model TrainingSet represents the structure of each object stored in Firebase:

export class TrainingSet {

    /**
     * Unique Identifier of this set
     */
    id:number;

    name:string;
    type: string;
    description: string;

}

Although my data is fetched successfully, I encounter some issues. While at Output 1 I observe an Object with two sub-objects containing the data, Output 2 displays empty objects, and Output 3 shows an array with elements named "V" that have unusual sub-items. I'm unsure about their nature.

If anyone can provide guidance on a more effective approach for this task, it would be greatly appreciated. I might not require an array if I could traverse the object tree accurately.

Answer №1

After some searching, I was able to solve my problem by following the steps outlined here: https://firebase.google.com/docs/database/web/lists-of-data#listen_for_value_events

I used a forEach loop to iterate through the snapshot and retrieve the values of each child element:
                    console.log(child.val());
                    trainingSets.push(child.val());
                });

The key point was remembering to call the val function on the child elements.

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