Sunday, November 10, 2013

OXMail Soup

I've bitten the hook on the first year free subscription to Open-Xchange from my domain registrar, Namecheap. I have to say, it's tasty. With email, calendar, tasks, contacts, infostore, it's positioned to compete against Outlook.

The client is an html5/ajax web app. If you've used gmail, you're already using this type of email client. There is a lot more eye candy then gmail, but it seems pretty responsive.

But, if you're like me, you don't like email in a browser tab. I want a dedicated app. You can do this on the desktop with Chrome - just go to the Tools menu and create an application shortcut. I create it in the application menu, and from there I can pin it to the bottom panel of my desktop. But this isn't available for Android. Not yet, although Chrome for android beta may fill this gap. So for now, I've created the dumbest android app ever. Actually, I probably won't win that prize... but without further ado:

Announcing OXMail - which does one thing, load oxwebmail mobile into a webview control.

Friday, November 8, 2013

Magic Coffee

One pattern that I wanted to implement for exspresso is used in php frameworks,  wherein PHP Magic is used redirect missing property or method references back to the main controller. For an example, take a look at this CodeIgniter Model class.

PHP magic uses __get, _set, and __call. These work much like Ruby's missing_method, and it would be nice to use the same kind of 'magic' in coffeescript, which means javascript.

So how do I implement this in javascript? Catching missing method exceptions won't be scalable. I need to find a different path to the same ends. I know that javascript gives me a different way to trap a missing method. Whenever a method or property is not found, the prototype chain is searched. Coffeescript uses this to implement class inheritance. I also know that the missing methods we're looking for will all be on the current controller instance.

If I can just insert the controller object into the prototype chain of each child object, I will get the same result. This is a simple version of technique I'm using in exspresso:

# Magic
# Dependency injection via prototype.
# Get all methods and properties in the prototype chain
metadata = (klass) ->

  chain = []
  props = {}
  proto = klass:: # starting point in the chain

  # Build an inheritance list
  until proto is Object::
    chain.push proto
    proto = Object.getPrototypeOf(proto)

  # Reverse list to process overrides in the correct order
  for proto in chain.reverse()
    if proto isnt Object::
      # Build the inherited properties table
      for key in Object.getOwnPropertyNames(proto)
        props[key] = Object.getOwnPropertyDescriptor(proto, key)


magic = (parent, klass, args...) ->

  # clone the object with all properties
  child = Object.create(parent, metadata(klass))
  # call the constructor
  klass.apply child, args

# Main Controller Class
class Controller

  constructor: ->
    @date = new Date()
    @user = magic(@, Model, 'Zaphod')

  println: (msg) ->
    console.log msg

class Model

  constructor: (name) ->
    @name = name

  hello: () ->
    @println @name + " " + @date

# Create the applications main controller
controller = new Controller()
# Call the models hello method.
# Missing methods and properties fallback to the controller.
(updated: to use google prettify rather than embedded gists. It makes it easier to focus on the code)