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).

Methods
#
A
C
I
N
Constants
NotFound = [404, {CONTENT_TYPE => "text/plain"}, []]
 
Attributes
[R] apps
Class Public methods
new(apps, catch=[404, 405])
# 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
Instance Public methods
<<(app)
Alias for: add
add(app)
Also aliased as: <<
# File lib/rack/cascade.rb, line 41
def add(app)
  @has_app[app] = true
  @apps << app
end
call(env)
# 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)
# File lib/rack/cascade.rb, line 46
def include?(app)
  @has_app.include? app
end