form.clj

(defpage "/" []
         (common/layout
          (form-to {:enctype "multipart/form-data"}
                   [:post "/upload"]
                   (label :file "File to upload:")
                   (file-upload :file)
                   [:br]
                   (submit-button "Upload"))))

upload-form.clj

; Show this page in case of success
(defpage "/success" []
  (common/layout
   [:h2 "File uploaded!"]))

; Show this page in case of failure
(defpage "/fail" []
  (common/layout
   [:h2 "Something went wrong"]))

;; S3 keys - replace with your keys
(def *server-spec* {:secret-key "SECRET KEY" :access-key "ACCESS KEY"})

(defpage [:post "/upload"] {:keys [file]}
  (if (= "0" (:size file))
    (do
      ;; Upload the file to the "s3-tut" bucket
      (binding [s3/*s3* (s3/service *server-spec*)]
        (s3/put! "s3-tut" (:tempfile file)))
      (resp/redirect "/success"))
    (resp/redirect "/fail")))

upload.clj

(ns file-uploadr.views.upload
  (:require [file-uploadr.views.common :as common]
            [noir.content.pages :as pages]
            [noir.response :as resp]
            [noir.util.s3 :as s3])
  (:use noir.core
        hiccup.core
        hiccup.page-helpers
        hiccup.form-helpers))

(defpage "/" []
         (common/layout
           [:p "Welcome to file-uploadr"]))