Firestore Observables to Promises

Update 2/26/24

This post is out of date since Firebase 9. For latest Firebase posts, seeCode.Build.

I am crazy, so I created a quick reference. Let me know if I missed one!

Note:

afa = AngularFireAuth
afs = AngularFirestore

but should be same premise in any framework.

constfoo=awaitthis.afs.doc(`docPath`).valueChanges().pipe(take(1)).toPromise();

constfoo=(awaitthis.afs.doc('docPath').get().toPromise()).data();

constfoo=(awaitthis.afs.doc('docPath').get().pipe(take(1)).toPromise()).data();

constfoo=(awaitthis.afs.doc('docPath').snapshotChanges().pipe(take(1)).toPromise()).payload.data();

But the shortest is:

constfoo=(awaitthis.afs.doc('docPath').ref.get()).data();

constfoo=awaitthis.afs.collection('colPath').valueChanges().pipe((take(1))).toPromise();

constfoo=(awaitthis.afs.collection('colPath').snapshotChanges().pipe(take(1)).toPromise()).map((m)=>m.payload.doc.data());

constfoo=(awaitthis.afs.collection('colPath').get().toPromise()).docs.map((m)=>m.data());

or (overkill from last version)

constfoo=(awaitthis.afs.collection('colPath').get().pipe(take(1)).toPromise()).docs.map((m)=>m.data());

constfoo=(awaitthis.afs.collection('colPath').ref.get()).docs.map((m)=>m.data());

As you may have noticed...

constbar=awaitthis.afa.currentUser;

... does not load correctly in a lot of cases.

So try these:

constbar=awaitthis.afa.authState.pipe(take(1)).toPromise();

or (authstatechanged is most accurate)

constbar=awaitnewObservable((observer:any)=>{this.afa.onAuthStateChanged(observer)}).pipe(take(1)).toPromise();

constbar=awaitnewPromise((resolve:any,reject:any)=>this.afa.onAuthStateChanged((user)=>{user?resolve(true):resolve(false);},(e:any)=>reject(e)));

or (the shortest)

constbar=awaitthis.afa.user.pipe(take(1)).toPromise();

And anywhere you can usetake(1) you can usefirst() if you want to emit an error.

For further actions, you may consider blocking this person and/orreporting abuse