如何使用Angular Firestore（Angular 7）返回Firebase文档属性？

Question

I'm trying to get Firebase document property based on this model:

I've already found a document using the following code:

//Users - collection name, uid - document uid.

Next, I'm trying to get isAdmin property using the following line of code:

In the results I receive undefined.

How it can be resolved? I need to return isAdmin property value, but I don't get how to do it.

Answer 1

The solution was very easy:

canActivate(): Observable<boolean> {
  return this.auth.user$
    .pipe(
      switchMap(fireuser => this.userService.get(fireuser.uid).snapshotChanges()),
        map(document => document.payload.data().isAdmin) 
    )
}