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Decoupled Responsibilities in Javascript

I have been updating the North 51 Coding standards for the benefit of the NHS and I had to stick a couple of things onto Gist so I thought I would share them here as well as the code isn't specific to anything internal to us.

Some of our legacy javascript code is quite poor and we are addressing that at the moment. With this in mind, I want to promote nice decoupled Javascript functions that are namespaced and use Trullocks PubSub library https://github.com/trullock/PubSub/

In the examples below, I have broken out the functionality into seperate files so that the Javascript that manipulates the DOM is seperate from the the script that validates the user input and the script that handles communicating with the server. No function talks to another directly (apart from the internals) and all communication is done along the Bus. The beauty of this is:


  • That one bit of functionality can be separated out nicely
  • A fake event can be published on the bus for testing purposes
  • More than one function can subscribe to a published event (you can do multiple things such as logging in the background, and it avoids large 'manager' classes)

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