Ternary operator <img src = "">

Ionic Framework ionic-v3
1

I’m trying to create a ternary operator in a profile image, where when not logged in by facebook, display a default image

<ion-thumbnail>
      <img src="{{ photoPerfil ? 'facebook.photoUrl' : 'assets/imgs/fotoPerfil.png' }}" >
    </ion-thumbnail>

I am not able to create this ternario operator, photo profile is a Boolean variable, where if it comes from facebook it gets true

2

Why is facebook.photoUrl quoted? That would make it a literal string.