LinkJoins.cljs

(ns om-tutorial.core
  (:require [goog.dom :as gdom]
            [om.next :as om :refer-macros [defui]]
            [cljs.pprint :refer [pprint]]
            [om.dom :as dom]))

(enable-console-print!)

(def init-data
  {:current-user {:email "bob.smith@gmail.com" :things [[:thing/by-id 1] [:thing/by-id 2]]}
   :thing/by-id  {
                  1 {:id 1 :name "Hello"}
                  2 {:id 2 :name "There"}
                  }
   :items        [{:id 0 :title "Foo"}
                  {:id 1 :title "Bar"}
                  {:id 2 :title "Baz"}]})

(defmulti read om/dispatch)

(defmethod read :items
  [{:keys [query state]} k _]
  (let [st @state]
    {:value (om/db->tree query (get st k) st)}))

(defui Thing
  static om/Ident
  (ident [_ {:keys [id]}]
    [:thing/by-id id])
  static om/IQuery
  (query [_]
    '[:id :name])
  Object
  (initLocalState [this] {:a true})
  (render [this]
    (let [{:keys [name]} (om/props this)]
      (dom/div nil
        (dom/b nil (if (get (om/get-state this) :a) "A" "a"))
        (dom/button #js {:onClick (fn []
                                (println "Click")
                                (om/update-state! this update :a not))} name))
      )))

(def thing (om/factory Thing {:keyfn :id}))

(defn user [u]
  (let [{:keys [email things]} u]
    (dom/div nil
      (dom/ol nil (mapv #(thing %) things))
      (dom/div nil email))))

(defui Item
  static om/Ident
  (ident [_ {:keys [id]}]
    [:item/by-id id])
  static om/IQuery
  (query [_]
    [:id :title {[:current-user '_] [:email {:things (om/get-query Thing)}]}])
  Object
  (render [this]
    (let [{:keys [title current-user]} (om/props this)]
      (dom/li nil
        (dom/div nil title)
        (user current-user)
        ))))

(def item (om/factory Item))

(defui SomeList
  static om/IQuery
  (query [_]
    [{:items (om/get-query Item)}])
  Object
  (render [this]
    (dom/div nil
      (dom/ul nil
        (map item (-> this om/props :items))))))

(def reconciler
  (om/reconciler
    {:state  init-data
     :parser (om/parser {:read read})}))

(om/add-root! reconciler SomeList (gdom/getElement "app"))

(comment
  (pprint @reconciler))