Question

当对我的api端点有错误请求时，

wrap-cors不会返回访问控制标头。我相信这是因为我使用的异常处理程序可能会阻止中间件运行。我想知道如何仍然可以为此路由执行中间件并将cors标头附加到错误请求的响应中。

异常处理程序

(defn- bad-request-handler
  "Handles bad requests."
  [f]

  (f
    (ring/response {:status "bad request"})))

app

(def app
  (api
    {:exceptions {:handlers
                          {::ex/request-validation (bad-request-handler response/bad-request)}}}

    (POST "/" [] :body [item {(schema/required-key :item) schema/Bool}]
             :middleware [#(wrap-cors % :access-control-allow-origin [#".*"]
                                      :access-control-allow-methods [:post])]

             :responses {200 {:description "ok"}
                         400 {:description "bad request"}} item)))

Answer 1

我决定添加自己的标题，而不是使用r0man / ring-cors。我可以通过从请求中获取Access-Control-Allow-Methods的值来确定:request-method的内容。但是，这假设错误的请求处理程序将仅由有效路由调用。

(defn- append-cors
  "Allow requests from all origins"
  [methods]

  {"Access-Control-Allow-Origin"  "*"
   "Access-Control-Allow-Methods" methods})


(defn- bad-request-handler
  "Handles bad requests."
  [f]

  (fn [^Exception e data request]
    (->
      (f request)
      (update-in [:headers] merge (->
                                    (request :request-method)
                                    (name)
                                    (clojure.string/upper-case)
                                    (append-cors)))
      (assoc :body {:status "bad request"}))))

我仍然不太确定为什么只在允许请求时才添加cors标头。

如果使用异常处理程序，则无法执行中间件？

1 个答案: