class Rack::Cascade - rack-1.6.4 Documentation

# class Rack::Cascade

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).

### Constants

NotFound

### Attributes

apps[R]

### Public Class Methods

new(apps, catch=[404, 405]) click to toggle source

    # File lib/rack/cascade.rb, line 11
    def initialize(apps, catch=[404, 405])
      @apps = []; @has_app = {}
      apps.each { |app| add app }

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

### Public Instance Methods

<<(app)
Alias for: add
add(app) click to toggle source

    # File lib/rack/cascade.rb, line 41
    def add(app)
      @has_app[app] = true
      @apps << app
    end

Also aliased as: <<
call(env) click to toggle source

    # File lib/rack/cascade.rb, line 19
    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

include?(app) click to toggle source

    # File lib/rack/cascade.rb, line 46
    def include?(app)
      @has_app.include? app
    end