Functional HTTP request

request.clj

(ns request)

(defn request [] {})
(defn body    [] {})
(defn file    [] {})

(defn set-url
  [request url]
  (assoc request :url url))

(defn set-method
  [request method]
  (assoc request :method method))

(defn set-body
  [request body]
  (assoc request :body body))

(defn set-multipart
  [body]
  (assoc body :multipart true))

(defn add-multipart-field
  [body k v]
  (assoc body k v))

(defn add-multipart-file
  [body file]
  (assoc body :file file))

(defn set-content-disposition
  [file content-disposition]
  (assoc file :content-disposition content-disposition))

(defn set-content-disposition-param
  [file k v]
  (assoc-in file [:content-disposition-params k] v))

(defn add-header
  [file header value]
  (assoc file header value))

(defn send-request
  [request]
  (when-not (request :method) (throw (IllegalArgumentException.
                                       "Request method must be set")))
  ;; etc etc etc other checks go here
  (println "Doing the thing with the request"))


;;;; App setup

(def api-password "aoesndaoe8994d',ndai")
(def project-id   "123")

(def my-file
  (-> (file)
    (set-content-disposition :form-data)
    (set-content-disposition-param :name "file")
    (add-header :Content-Transfer-Encoding "binary")))


;;;; Example usage ;;;;

(-> (request)
  (set-url    "http://example.org")
  (set-method :post)
  (set-body (-> (body)
              (set-multipart)
              (add-multipart-field :api_password api-password)
              (add-multipart-field :project_id   project-id)
              (add-multipart-file my-file)))
  (send-request))