require "active_support/inflector/methods" require "active_support/dependencies" module ActionDispatch class MiddlewareStack class Middleware attr_reader :args, :block, :klass def initialize(klass, args, block) @klass = klass @args = args @block = block end def name; klass.name; end def inspect klass.to_s end def build(app) klass.new(app, *args, &block) 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 unshift(klass, *args, &block) middlewares.unshift(build_middleware(klass, args, block)) end def initialize_copy(other) self.middlewares = other.middlewares.dup end def insert(index, klass, *args, &block) index = assert_index(index, :before) middlewares.insert(index, build_middleware(klass, args, block)) 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) index = assert_index(target, :before) insert(index, *args, &block) middlewares.delete_at(index + 1) end def delete(target) target = get_class target middlewares.delete_if { |m| m.klass == target } end def use(klass, *args, &block) middlewares.push(build_middleware(klass, args, block)) end def build(app = Proc.new) middlewares.freeze.reverse.inject(app) { |a, e| e.build(a) } end protected def assert_index(index, where) index = get_class index i = index.is_a?(Integer) ? index : middlewares.index { |m| m.klass == index } raise "No such middleware to insert #{where}: #{index.inspect}" unless i i end private def get_class(klass) if klass.is_a?(String) || klass.is_a?(Symbol) classcache = ActiveSupport::Dependencies::Reference converted_klass = classcache[klass.to_s] ActiveSupport::Deprecation.warn <<-eowarn Passing strings or symbols to the middleware builder is deprecated, please change them to actual class references. For example: "#{klass}" => #{converted_klass} eowarn converted_klass else klass end end def build_middleware(klass, args, block) Middleware.new(get_class(klass), args, block) end end end