I am pretty new to expo and firebase, and I have this error that I have no idea what the issue is. I am trying to fetch photos from firebase database. I know for sure the issue is not with firebase config because I can upload photos into firebase storage.
I suspect the issue is with exporting and importing firebase.
This is the error message I am getting:
[TypeError: _firebase.db.ref is not a function. (In '_firebase.db.ref('users/photos')', '_firebase.db.ref' is undefined)]
Note: I am using firebase v9
App.js file:
import { db } from './firebase';
export default function App() {
async function loadPhotos() {
try {
db.ref('users/photos')
.then(url => {
console.log('URL: ', url);
})
.catch(e => console.log(e));
console.log('Got here');
} catch (error) {
console.log('error', error);
}
}
...............
}
firebase.js file:
import firebase from 'firebase/compat/app';
import { getDatabase } from 'firebase/database';
const firebaseConfig = {
apiKey: '......',
authDomain: '.....',
projectId: '....',
storageBucket: '....',
messagingSenderId: '....',
appId: '.....',
measurementId: '....',
};
if (!firebase.apps.length) {
firebase.initializeApp(firebaseConfig);
}
export const db = getDatabase();
In v9 and later of the Firebase SDK, most functionality that was a method on the objects in the past, is now available as a top-level function.
So instead of db.ref('users/photos')
, you need to do ref(db, 'users/photos')
.
You're also missing a get
call, which is how you actually retrieve the data from the reference:
get(ref(db, 'users/photos'))
.then(url => {
console.log('URL: ', url);
})
.catch(e => console.log(e));
This is all pretty well documented in the Firebase documentation on reading data , so I recommend keeping that handy. Alternatively you can use the compat
paths in v9, to make the older syntax work as shown in the upgrade guide /
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