Ember.js token based authentication without a library

session.js

import Ember from 'ember';
import config from '../config/environment';
import fetch from 'ember-network/fetch';

const { Service, inject, RSVP } = Ember;

export default Service.extend({
  store: inject.service(),
  authenticationToken: undefined,
  currentUser: undefined,
  fetchCurrentUser() {
    return new RSVP.Promise((resolve, reject) => {
      if (this.get('authenticationToken')) {
        return fetch(`${config.apiHost}/me`, {
          method: 'GET',
          mode: 'cors',
          headers: {
            'Authorization': this.get('authenticationToken') ? 
              `Token ${this.get('authenticationToken')}` : undefined
          }
        }).then((response) => {
          if (response.status === 200) {
            return response.json();
          }

          return reject();
        }).then((json) => {
          if (json.id) { // unfortunate need due to the fetch() function
            this.get('store').pushPayload({ user: json });

            this.set('currentUser', this.get('store').peekRecord('user', json.id));

            if (Raven) {
              Raven.setUserContext({ user_id: this.get('currentUser.id') });
            }

            return resolve(this.get('currentUser'));
          }

          return reject(); // unfortunate need due to the fetch() function
        }).catch(() => {
          return reject(); // unfortunate need due to the fetch() function
        });
      }

      return reject();
    });
  },
  login(authenticationToken) {
    return new RSVP.Promise((resolve, reject) => {
      this.set('authenticationToken', authenticationToken);

      this.fetchCurrentUser().then((user) => {
        localStorage.setItem('yourapp_authentication_token', authenticationToken);
        return resolve(user);
      }).catch(() => {
        return reject();
      });
    });
  },
  logout() {
    return new RSVP.Promise((resolve, reject) => {
      if (this.get('currentUser')) {
        localStorage.removeItem('yourapp_authentication_token');
        this.set('authenticationToken', null);
        this.set('currentUser', null);
        return resolve();
      }

      return reject();
    });
  }
});

// routes/application.js
// this ensures the /me gets loaded before app goes to other route model()'s:
import Ember from 'ember';

const { Route } = Ember;

export default Route.extend({
  model() {
    if (window && window.localStorage) { // ember fastboot edit
      this.get('session').set(
        'authenticationToken', localStorage.getItem('yourapp_authentication_token')
      );

      return this.get('session').fetchCurrentUser().then(() => {
        return; // finally() doesn't work somehow, Bluebird > Ember.RSVP
      }).catch(() => {
        return;
      });
    }
  }
});

// routes/base.js
// you can call login() and logout functions throughout the app route and controller functions:
// it needs ember-route-action-helper package
// like: this.send('login', model.get('authenticationToken'));
import Ember from 'ember';
import ScrollResetMixin from 'frontend/mixins/scroll-reset';

export default Ember.Route.extend(ScrollResetMixin, {
  actions: {
    login(authenticationToken) {
      this.get('session').login(authenticationToken).then((user) => {
        if (user.isAdmin) {
          return this.transitionTo('admin.index');
        }
        return this.transitionTo('public.profile');
      });
    },
    logout() {
      this.get('session').logout().then(() => {
        this.transitionTo('public');
      }); // maybe a flashMessage
    }
  }
});

// initializers/session.js
// to make this.get('session') available everywhere:
export default {
  name: 'session',
  after: 'ember-data',

  initialize(app) {
    app.inject('route', 'session', 'service:session');
    app.inject('controller', 'session', 'service:session');
    app.inject('application', 'session', 'service:session');
    app.inject('component', 'session', 'service:session');
  }
};

// adapters/application.js
// to ensure that we send the authenticationToken for Ember Data requests:
import config from 'frontend/config/environment';
import Ember from 'ember';
import DS from 'ember-data';

const { inject, computed } = Ember;

export default DS.RESTAdapter.extend({
  host: config.apiHost,
  session: inject.service('session'),
  headers: computed('session.authenticationToken', function() { // this part is awesome:
    return {
      'Authorization': this.get('session.authenticationToken') ? 
        `Token ${this.get('session.authenticationToken')}` : undefined
    };
  })
});