How to display in HTML that const and manipulate?

Good afternoon guys! I am developing an app and I need it in the html file, have a list of the users of the firebase database and then need to create a conditional to manage the permissions when the user is in some category ... in my code, I have:

this.ref.on('value', resp => {
        this.rooms = [];
        this.rooms = snapshotToArray(resp);
      });

And the snapshot looks like this:

export const snapshotToArray = snapshot => {
  let returnArr = [];

  snapshot.forEach(childSnapshot => {
    let item = childSnapshot.val();
    returnArr.push(item);
  });

  return returnArr;
};

The firebase has the following path: users / teachers and users / responsibles how would the conditional to verify that the current user is in teachers or responsible?