Writing a structured Om application with requests, but not om.next

Question

I'd like to write an application in Om - a GitHub issues viewer in particular. To retrieve issues from GitHub, I'll need to XHR request them, and there'll be the action of marking issues as 'viewed' by sending a request back to GitHub.

There's quite a bit of documentation for using the current version of Om without async/http calls, and quite a bit for using Om.next with them, but I'm just getting started and feel like Om.next isn't the right place for a complete ClojureScript newbie to dive in.

Is there documentation and are there patterns for using the current stable version of Om (0.8.x) with remote resources, that'd lead to a clean architecture for this kind of app? The big applications that are using Om in production, like CircleCI - are they using Om.next? If not, what's the commonly-accepted pattern for requests?

score 2 · Answer 1 · answered Feb 01 '16 at 21:17

CircleCI frontend is currently written in Om, but they have plans to migrate to Om.next, and they explain why.

Regarding Om, there is a repository dedicated to "idioms and patterns", linked from the tutorial section. I would not say that anything is written in marble though, be prepared to experiment a bit.

score 1 · Accepted Answer · answered Feb 04 '16 at 09:12

I think, that you can dive in om's real-world example. They are using Google Closure's XhrIo for async http calls.

(defn edn-xhr [{:keys [method url data on-complete]}]
  (let [xhr (XhrIo.)]
    (events/listen xhr goog.net.EventType.COMPLETE
      (fn [e]
        (on-complete (reader/read-string (.getResponseText xhr)))))
    (. xhr
      (send url (meths method) (when data (pr-str data))
        #js {"Content-Type" "application/edn"}))))

Communicating server on user change

(defn on-edit [id title]
  (edn-xhr
    {:method :put
     :url (str "class/" id "/update")
     :data {:class/title title}
     :on-complete
     (fn [res]
       (println "server response:" res))}))

Data loading on om.core/IWillMount

(defn classes-view [app owner]
  (reify
    om/IWillMount
    (will-mount [_]
      (edn-xhr
        {:method :get
         :url "classes"
         :on-complete #(om/transact! app :classes (fn [_] %))}))
    om/IRender
    (render [_]
      (dom/div #js {:id "classes"}
        (dom/h2 nil "Classes")
        (apply dom/ul nil
          (map
            (fn [class]
              (let [id (:class/id class)]
                (om/build editable class
                  {:opts {:edit-key :class/title
                          :on-edit #(on-edit id %)}})))
            (:classes app)))))))

This is not answer for your question, but you can dive in om examples

Writing a structured Om application with requests, but not om.next

2 Answers2