import Controller from '@ember/controller'; import { computed } from '@ember/object'; export default Controller.extend({ queryParams: { sortBy: 'sort', status: 'status', source: 'source', search: { as: 'filter', replace: true, }, }, externalSources: computed('items', function() { const sources = this.items.reduce(function(prev, item) { return prev.concat(item.ExternalSources || []); }, []); // unique, non-empty values, alpha sort return [...new Set(sources)].filter(Boolean).sort(); }), });