Class: Rack::Cascade

Inherits:
Object
  • Object
show all
Defined in:
rack/rack/cascade.rb

Overview

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).

Constant Summary

NotFound =
[404, {"Content-Type" => "text/plain"}, []]

Instance Attribute Summary (collapse)

Instance Method Summary (collapse)

Constructor Details

- (Cascade) initialize(apps, catch = [404, 405])

Returns a new instance of Cascade



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# File 'rack/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 Attribute Details

- (void) apps (readonly)

Returns the value of attribute apps



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# File 'rack/rack/cascade.rb', line 9

def apps
  @apps
end

Instance Method Details

- (void) add(app) Also known as: <<



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# File 'rack/rack/cascade.rb', line 41

def add app
  @has_app[app] = true
  @apps << app
end

- (void) call(env)



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# File 'rack/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

- (Boolean) include?(app)

Returns:

  • (Boolean)


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# File 'rack/rack/cascade.rb', line 46

def include? app
  @has_app.include? app
end