如何使用(ruby)机架中间件组件设置cookie?

我正在为一个需要有条件地设置cookie的rails应用程序编写机架中间件组件。 我目前正试图设法设置cookie。 从谷歌搜索它似乎应该工作:

class RackApp def initialize(app) @app = app end def call(env) @status, @headers, @response = @app.call(env) @response.set_cookie("foo", {:value => "bar", :path => "/", :expires => Time.now+24*60*60}) [@status, @headers, @response] end end 

它不会给出错误,但也不会设置cookie。 我究竟做错了什么?

如果要使用Response类,则需要从在堆栈中进一步调用中间件层的结果中实例化它。 此外,您不需要像这样的中间件的实例变量,并且可能不希望以这种方式使用它们(@ status等在请求被提供后将保留在中间件实例中)

 class RackApp def initialize(app) @app = app end def call(env) status, headers, body = @app.call(env) # confusingly, response takes its args in a different order # than rack requires them to be passed on # I know it's because most likely you'll modify the body, # and the defaults are fine for the others. But, it still bothers me. response = Rack::Response.new body, status, headers response.set_cookie("foo", {:value => "bar", :path => "/", :expires => Time.now+24*60*60}) response.finish # finish writes out the response in the expected format. end end 

如果您不知道自己在做什么,可以直接修改cookie标头,如果您不想实例化新对象。

您还可以使用Rack::Utils库来设置和删除标题,而无需创建Rack :: Response对象。

 class RackApp def initialize(app) @app = app end def call(env) status, headers, body = @app.call(env) Rack::Utils.set_cookie_header!(headers, "foo", {:value => "bar", :path => "/"}) [status, headers, body] end end