Rails 4 before_action, pass parameters to invoked method

before_action only: [:show, :edit, :update, :destroy] do
  set_support("value")
end

A short and one-liner answer (which I personally prefer for callbacks) is:

before_action except:[:index, :show] { method :param1, :param2 }

Another example:

after_filter only:[:destroy, :kerplode] { method2_namey_name(p1, p2) }

You can use a lambda:

class SupportsController < ApplicationController
  before_action -> { set_support("value") }, 
    only: [:show, :edit, :update, :destroy]
  ...

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