Contents

# frozen_string_literal: true

module Rack
  # Rack::Cascade tries a request on several apps, and returns the
  # first response that is not 404 or 405 (or in a list of configurable
  # status codes).

  class Cascade
    NotFound = [404, { CONTENT_TYPE => "text/plain" }, []]

    attr_reader :apps

    def initialize(apps, catch = [404, 405])
      @apps = []
      apps.each { |app| add app }

      @catch = {}
      [*catch].each { |status| @catch[status] = true }
    end

    def call(env)
      result = NotFound

      last_body = nil

      @apps.each do |app|
        # The SPEC says that the body must be closed after it has been iterated
        # by the server, or if it is replaced by a middleware action. Cascade
        # replaces the body each time a cascade happens. It is assumed that nil
        # does not respond to close, otherwise the previous application body
        # will be closed. The final application body will not be closed, as it
        # will be passed to the server as a result.
        last_body.close if last_body.respond_to? :close

        result = app.call(env)
        last_body = result[2]
        break unless @catch.include?(result[0].to_i)
      end

      result
    end

    def add(app)
      @apps << app
    end

    def include?(app)
      @apps.include?(app)
    end

    alias_method :<<, :add
  end
end

Version data entries

9 entries across 9 versions & 1 rubygems

Version	Path
rack-2.1.4.4	lib/rack/cascade.rb
rack-2.1.4.3	lib/rack/cascade.rb
rack-2.1.4.2	lib/rack/cascade.rb
rack-2.1.4.1	lib/rack/cascade.rb
rack-2.1.4	lib/rack/cascade.rb
rack-2.1.3	lib/rack/cascade.rb
rack-2.1.2	lib/rack/cascade.rb
rack-2.1.1	lib/rack/cascade.rb
rack-2.1.0	lib/rack/cascade.rb