Simple Strong Parameters in Sinatra

example-app.rb

require 'sinatra/base'
require 'sinatra/strong-params'

class ExampleApp < Sinatra::Base
  configure do
    register Sinatra::StrongParams
  end
  
  get '/', allows: [:search] do
    # Only the 'search' parameter will make it to the execution scope.
  end
  
  post '/search', needs: [:search, :_csrf] do
    # Will only ever return if both the 'search' and '_csrf' parameters are present.
    #   Otherwise, it will raise an instance of RequiredParamMissing
  end
  
  error RequiredParamMissing do
    # Handle parameter failures here.
    [400, "No dice"]
  end
end