CartoDB/cartodb20

  /**
   *  Synced table model
   */

  cdb.admin.TableSynchronization = cdb.core.Model.extend({

    _X:         1.2,  // Multiply current interval for this number
    _INTERVAL:  1500, // Interval time between poll checkings
    _STATES:    ['created', 'failure', 'success', 'syncing', 'queued'],

    defaults: {
      name: '',
      url: '',
      state: '',
      run_at: 0,
      ran_at: 0,
      retried_times: 0,
      interval: 0,
      error_code: 0,
      error_message: '',
      service_name: '',
      service_item_id: '',
      content_guessing: true,
      type_guessing: true
    },

    url: function(method) {
      var version = cdb.config.urlVersion('synchronization', method);

      var base = '/api/' + version + '/synchronizations/';
      if (this.isNew()) {
        return base;
      }
      return base + this.id;
    },

    initialize: function() {
      this.bind('destroy', function() {
        this.unset('id');
      });
    },

    toJSON: function() {
      var c = _.clone(this.attributes);

      var d = {
        url:      c.url,
        interval: c.interval,
        content_guessing: c.content_guessing,
        type_guessing: c.type_guessing,
        create_vis: c.create_vis
      };

      if (c.type === "remote") {
        _.extend(d, {
          remote_visualization_id: c.remote_visualization_id,
          create_vis: false,
          value: c.value
        });
      }

      if(c.id !== undefined) {
        d.id = c.id;
      }

      // Comes from a service?
      if(c.service_name) {
        d.service_name = c.service_name;
        d.service_item_id = c.service_item_id;
      }

      return d;
    },

    syncNow: function(callback) {
      $.ajax({
        url:  cdb.config.prefixUrl() + this.url() + '/sync_now',
        type: 'PUT'
      }).always(callback)
    },

    // Checks for poll to finish
    pollCheck: function(i) {
      var self = this;
      var interval = this._INTERVAL;

      this.pollTimer = setInterval(request , interval);

      function request() {
        self.destroyCheck();

        self.fetch({
          error: function(m, e) {
            self.set({
              error_message:  e.statusText || "",
              state:          'failure'
            });
          }
        });

        interval = interval * self._X;

        self.pollTimer = setInterval(request, interval);
      }
    },

    destroyCheck: function() {
      clearInterval(this.pollTimer);
    },

    isSync: function() {
      return !this.isNew();
    },

    linkToTable: function(table) {
      var self = this;
      if (table.has('synchronization')) {
        this.set(table.get('synchronization'));
      }

      table.bind('change:synchronization', function() {
        self.set(table.get('synchronization'));
      }, table);

      table.bind('destroy', function destroy() {
        self.unbind(null, null, table);
        self.destroy();
      }, table);
      //TODO: manage table renaming
    }

  });