open-nomad/ui/app/routes/application.js

import { inject as service } from '@ember/service';
import { next } from '@ember/runloop';
import Route from '@ember/routing/route';
import { AbortError } from '@ember-data/adapter/error';
import RSVP from 'rsvp';

export default Route.extend({
  config: service(),
  system: service(),
  store: service(),
  token: service(),

  queryParams: {
    region: {
      refreshModel: true,
    },
  },

  resetController(controller, isExiting) {
    if (isExiting) {
      controller.set('error', null);
    }
  },

  beforeModel(transition) {
    const fetchSelfTokenAndPolicies = this.get('token.fetchSelfTokenAndPolicies')
      .perform()
      .catch();

    return RSVP.all([
      this.get('system.regions'),
      this.get('system.defaultRegion'),
      fetchSelfTokenAndPolicies,
    ]).then(promises => {
      if (!this.get('system.shouldShowRegions')) return promises;

      const queryParam = transition.to.queryParams.region;
      const defaultRegion = this.get('system.defaultRegion.region');
      const currentRegion = this.get('system.activeRegion') || defaultRegion;

      // Only reset the store if the region actually changed
      if (
        (queryParam && queryParam !== currentRegion) ||
        (!queryParam && currentRegion !== defaultRegion)
      ) {
        this.system.reset();
        this.store.unloadAll();
      }

      this.set('system.activeRegion', queryParam || defaultRegion);

      return promises;
    });
  },

  // Model is being used as a way to transfer the provided region
  // query param to update the controller state.
  model(params) {
    return params.region;
  },

  setupController(controller, model) {
    const queryParam = model;

    if (queryParam === this.get('system.defaultRegion.region')) {
      next(() => {
        controller.set('region', null);
      });
    }

    return this._super(...arguments);
  },

  actions: {
    didTransition() {
      if (!this.get('config.isTest')) {
        window.scrollTo(0, 0);
      }
    },

    willTransition() {
      this.controllerFor('application').set('error', null);
    },

    error(error) {
      if (!(error instanceof AbortError)) {
        this.controllerFor('application').set('error', error);
      }
    },
  },
});