Editing data retrive from api inside Ember.js application

I'm new to all those frameworks/js thing - so sorry if I want to do something that I'm not allowed.

I'm retrieving json data from api of another application.

In ember component I would like to display data from that json but because It can be a very long string I would like to display only first 256 characters. I'm displaying it via is there a way to cut it after 256 characters so it wont break the app view ?