js/widgets/follow-btn.js

/**
 * Follow button
 */
define(['jquery', 'auth', 'i18n'], function($, Auth, i18n) {
    'use strict';

    var DEFAULTS = {
        follow_icon: 'glyphicon glyphicon-eye-open',
        following_icon: 'glyphicon glyphicon-eye-close',
        follow_label: i18n._('Follow'),
        following_label: i18n._('Following')
    }

    // Handle featured button
    $('.btn-follow').click(function() {
        var $this = $(this),
            $icon = $this.find('.glyphicon,.fa'),
            follow_icon = $this.data('follow-icon') || DEFAULTS.follow_icon,
            following_icon = $this.data('following-icon') || DEFAULTS.following_icon,
            has_text = $.trim($this.text()).length > 0;

        if (!Auth.need_user(i18n._('You need to be logged in to follow.'))) {
            return false;
        }

        if ($this.hasClass('active')) {
            $.ajax({
                url: $this.data('api-url'),
                type: 'DELETE',
                success: function(data) {
                    var label = $this.data('follow-label') || DEFAULTS.follow_label;

                    $icon.removeClass(following_icon).addClass(follow_icon);
                    $this.removeClass('active')
                        .attr('title', label).attr('data-original-title', label)
                        .tooltip('fixTitle');

                    if (has_text) {
                        $this.text(label).prepend($icon);
                    }

                }
            })
        } else {
            $.post($this.data('api-url'), function(data) {
                var label = $this.data('following-label') || DEFAULTS.following_label

                $icon.removeClass(follow_icon).addClass(following_icon);
                $this.addClass('active')
                    .attr('title', label).attr('data-original-title', label)
                    .tooltip('fixTitle');

                if (has_text) {
                    $this.text(label).prepend($icon);
                }
            });
        }

        return false;
    });

});