pubsub-observable.js

define(function(require) {
  var ko = require('knockout');
  
  function observeEvent(pubsub, options) {
    var o = ko.observable();
    
    Object.keys(options).forEach(function(evt) {
      var value = options[evt];

      pubsub.on(evt, function() {
        o(value);
      });
    });
    
    // return read-only version to discourage bad coding patterns
    return ko.computed(function() {
      return o();
    });
  }
  
  return observeEvent;
});

some-model.js

define(function(require) {
  var ko = require('knockout');
  var pubsub = require('pubsub');
  
  var observe = require('pubsub-observable');
  
  function Model() {
    this.isAirRecording = observe(pubsub, {'airrecording:started': true, 'airrecording:stopped': false});
  }
});