[chef] Making available configuration data of Database node to the WebApp node

[Denis Weerasiri < >]

Hi,

I am trying to learn cookbook language by writing a cookbook to set up a LAMP stack in two different nodes for MySQL and PHP.

I was looking at this https://github.com/amazonwebservices/opsworks-example-cookbooks/blob/master/phpapp/recipes/appsetup.rb and it has 

variables(
      :host =>     (deploy[:database][:host] rescue nil),

      :user =>     (deploy[:database][:username] rescue nil),

      :password => (deploy[:database][:password] rescue nil),

      :db =>       (deploy[:database][:database] rescue nil),

      :table =>    (node[:phpapp][:dbtable] rescue nil)

    )

Does any body knows what this "variable" construct tries to do? I don't understand what is meant by "=>" and "deploy" means in this recipe.

--

Thanks,
Denis