firebase add to document code example

Example 1: firestore set a document

let data = {
  name: 'Los Angeles',
  state: 'CA',
  country: 'USA'
};

// Add a new document in collection "cities" with ID 'LA'
let setDoc = db.collection('cities').doc('LA').set(data);

Example 2: firebase functions add to database

import * as functions from 'firebase-functions';
import * as admin from 'firebase-admin';
admin.initializeApp(functions.config().firebase);

exports.onMsgAdded = functions.database.ref('/users/{uid}/messages/{to_uid}/{msg}').onCreate((snap, context) =>{
    const data = snap.val();
    const msgRoot = admin.database().ref('/users/' + context.params.to_uid + '/messages/' + context.params.uid);
    return msgRoot.set(data);
});

Example 3: document.set() firebasefirestore java

// Create an initial document to update.var frankDocRef = db.collection("users").doc("frank");frankDocRef.set({    name: "Frank",    favorites: { food: "Pizza", color: "Blue", subject: "recess" },    age: 12});// To update age and favorite color:db.collection("users").doc("frank").update({    "age": 13,    "favorites.color": "Red"});