Implementing Email Notifications in Open Event Frontend

In Open Event Frontend, we have a ‘settings/email-preferences’ route where we give the user an access to change the email-notifications that he wants to subscribe for a specific event. For now, we are having three notifications for an event which the user can toggle to on and off. To achieve this, we did the following things:

First, we create a model for email-notifications so as to have a skeleton of the data that we are going to receive from the JSON API.

export default ModelBase.extend({

  /**
   * Attributes
   */

  nextEvent           : attr('boolean'),
  newPaper            : attr('boolean'),
  sessionAcceptReject : attr('boolean'),
  sessionSchedule     : attr('boolean'),
  afterTicketPurchase : attr('boolean'),

  /**
   * Relationships
   */
  user  : belongsTo('user'),
  event : belongsTo('event')
});

Thus, above code shows the attributes which we are going to receive via our JSON API and we will render the data accordingly on the page. We have established the relationship of the email-notifications with user and event so that in future wherever needed, we can query the records from either side. The client side has checkboxes to show the data to the user. Following is the format of the checkboxes:

<div class="row">
        <div class="column eight wide">
          {{t 'New Paper is Submitted to your Event'}}
        </div>
        <div class="ui column eight wide right aligned">
          {{ui-checkbox class='toggle' checked=preference.newPaper onChange=(pipe-action (action (mut preference.newPaper)) (action 'savePreference' preference))}}
        </div>
      </div>
      <div class="row">
        <div class="column eight wide">
          {{t 'Change in Schedule of Sessions in your Event'}}
        </div>
        <div class="ui column eight wide right aligned">
          {{ui-checkbox class='toggle' checked=preference.sessionSchedule onChange=(pipe-action (action (mut preference.sessionSchedule)) (action 'savePreference' preference))}}
        </div>
      </div>

The states of the checkboxes are determined by the data that we receive from the API. For example, if for a record, the API returns:

nextEvent           : true,
newPaper            : false,
sessionAcceptReject : true,
sessionSchedule     : false,
afterTicketPurchase : false,

Then, the respective states will be shown by the checkbox and the user can toggle the states to change the email-preferences as they want.

Thus to get the data sent by the server to the client, we return it as a model and query it as:

model() {
    return this.get('authManager.currentUser').query('emailNotifications', { include: 'event' });
}

As we can see, as mentioned earlier, we kept the relationships so that we can query the email-notifications specific to the particular user or specific to particular event. Here, we are showing a user’s email-notifications and hence we queried it with the user relationship.
The authManager loads the currentUser and queries the email-notifications for a particular use. We also want the event details to show the email-preferences, hence we include the event model to be fetched in the query also.

We also let the user change the preferences of the email-notifications so that he can customise the notifications and keep the ones he wants to receive. We implement the updating of email-preferences API as follows:

Whenever a user toggles the checkbox, we are having an action as called ‘savePreference’, which handles the updation of the preferences.

 

{{ui-checkbox class='toggle' checked=preference.newPaper onChange=(pipe-action (action (mut preference.newPaper)) (action 'savePreference' preference))}}

savePreference(emailPreference) {
      emailPreference.save()
        .then(() => {
          this.get('notify').success(this.l10n.t('Email notifications updated successfully'));
        })
        .catch(() => {
          emailPreference.rollbackAttributes();
          this.get('notify').error(this.l10n.t('An unexpected error occurred.'));
        });
    }

We are passing the parameter(the whole preference object to the action), and then just performing a ‘save’ method on it which will send a PATCH request to the server to update the data.

Thus, in this way, the user can change the email-notification preferences in the Open Event Frontend.

Resources:
Ember data Official guide
Blog on Models and Ember data by Daniel Lavigne: Learning Ember.js Part 4: Models

Source code: https://github.com/fossasia/open-event-frontend/pull/537/files