some puzzled about examples code

[bugeb]

The following code from examples collection.clj

(defn check-content-type [ctx content-types]
  (if (#{:put :post} (get-in ctx [:request :request-method]))
    (or 
     (some #{(get-in ctx [:request :headers "content-type"])}
           content-types)
     [false {:message "Unsupported Content-Type"}])
    true))

(defresource list-resource
  :available-media-types ["application/json"]
  :allowed-methods [:get :post]
  :known-content-type? #(check-content-type % ["application/json"])
  ......)

:allowed-methods had checked request method, but check-content-type function once again check request method. there are other purpose？

(defn content-types-check [ctx content-types]
  (if (some #{(get-in ctx [:request :headers "content-type"])} content-types)
    true
    false))

[ordnungswidrig]

check-content-type check if the request content-type supported. This is only done for the PUT and POST method and defaults to true for GET and the others. A GET request doesn't carry a content-type typically and this would make the known-content-type? decision return false.

[bugeb]

Thanks.