require "active_support/inflector/methods" require "active_support/dependencies" module ActionDispatch class MiddlewareStack class Middleware attr_reader :args, :block, :name, :classcache def initialize(klass_or_name, *args, &block) @klass = nil if klass_or_name.respond_to?(:name) @klass = klass_or_name @name = @klass.name else @name = klass_or_name.to_s end @classcache = ActiveSupport::Dependencies::Reference @args, @block = args, block end def klass @klass || classcache[@name] end def ==(middleware) case middleware when Middleware klass == middleware.klass when Class klass == middleware else normalize(@name) == normalize(middleware) end end def inspect klass.to_s end def build(app) klass.new(app, *args, &block) end private def normalize(object) object.to_s.strip.sub(/^::/, '') end end include Enumerable attr_accessor :middlewares def initialize(*args) @middlewares = [] yield(self) if block_given? end def each @middlewares.each { |x| yield x } end def size middlewares.size end def last middlewares.last end def [](i) middlewares[i] end def initialize_copy(other) self.middlewares = other.middlewares.dup end def insert(index, *args, &block) index = assert_index(index, :before) middleware = self.class::Middleware.new(*args, &block) middlewares.insert(index, middleware) end alias_method :insert_before, :insert def insert_after(index, *args, &block) index = assert_index(index, :after) insert(index + 1, *args, &block) end def swap(target, *args, &block) insert_before(target, *args, &block) delete(target) end def delete(target) middlewares.delete target end def use(*args, &block) middleware = self.class::Middleware.new(*args, &block) middlewares.push(middleware) end def build(app = nil, &block) app ||= block raise "MiddlewareStack#build requires an app" unless app middlewares.reverse.inject(app) { |a, e| e.build(a) } end protected def assert_index(index, where) i = index.is_a?(Integer) ? index : middlewares.index(index) raise "No such middleware to insert #{where}: #{index.inspect}" unless i i end end end