How to type with typescript a angularfire observable?

Question

I am trying to use angularfire properly and type it. But I always have this error :

 getMessages(): Observable<ChatMessage[]> {
    return this.db.collection('chat').valueChanges();

}

I tried this workaround, but is not clean

 getMessages(): Observable<ChatMessage[]> {
    return <any>this.db.collection('chat').valueChanges();

Answer 1

You need to use

this.db.collection<ChatMessage>('chat')

As you can see here