How to create a Rails-like before filter in Sinatra?

Question

class Foo
  def do_before
    ...
  end

  def do_something
    ...

Is there a way to run do_before method before each other method in the Foo class (like do_something)?

It seems that the Sinatra before block runs before each HTTP request, which has nothing to do with this class.

EDIT: As Michael pointed out in the comments, the only similar functionality that Rails offers is in the Controller. However, both Rails and Sinatra offer something similar to this functionality.

Answer 1

As iain pointed out in the comments, the example you specify is not specific to Rails/Sinatra. I'm assuming you want before filter like the ones in Rails and this is what Sinatra offers:

Sinatra's modular apps:

class Foo < Sinatra::Base

  before do
    "Do something"
  end

  get '/' do
    "Hello World"
  end
end

class Bar < Sinatra::Base

  before do
    "Do something else"
  end

  get '/' do
    "Hello World"
  end
end

In your config.rb file,

require 'foo.rb'
require 'bar.rb'

map '/foo' do
  run Foo
end

map '/bar' do
  run Bar
end

This is the nearest analogy for a Rails controller in Sinatra. Create more classes like this and you'll have a similar functionality (similar, but may not be the same as you might expect in Rails world).