Error: model.get is not a function - emberjs

I want to redirect my contacts page to contacts.show page show that while loading contacts page it will display the default first contact details.

But in contact page loading is got following error

Error while processing route: contacts.index model.get is not a function TypeError: model.get is not a function

TypeError: model.get is not a function

contact.js

const { RSVP, $ } = Ember;
import Ember from 'ember';
export default Ember.Route.extend({
model() {
    return $.getJSON('/api/contacts')
},
redirect(model, transition) {
    this.transitionTo('contacts.show',model.get('firstObject'));
}
});