hypercrud livecoding demo

gistfile1.clj

;; Datomic uses immutability to make read queries come from in-app process instead of network. 
;; Web service backed by datomic can have same performance characteristics - browser ajax read 
;; queries can come from in-browser. Changes browser programming model - can code as if all data 
;; is local. Removes all read-IO from browser apps. Components that do IO can now compose. 
;; Still ACID & relational queries like datomic.
;;
;; Other solutions to same problem: Facebook Relay/GraphQL, Netflix Falcor, Om Next



;; This file is app code
;; Only pure functions in this file. Programming model is pure functions against local data.

(let [entry-hc-node {:href "/api?prod=true"}] 
     
      ;; resolve a node in the data graph from the server.
      ;; In dev this is async and queries the server, and the below view-fn is invoked async.
      ;; In prod, the data is already local, so the view-fn is invoked synchronously, no network i/o.
      [hypercrud/resolve client entry-hc-node
     
        ;; pure view fn (React.js component)
        (fn [entry-hc-node]
          (let [communities (-> entry-hc-node :links :communities)]
            
            ;; Arbitrarily resolve more nodes, view code access whatever nodes it wants.
            ;; In dev this is network i/o, in prod the data is local.
            [hypercrud/resolve client communities
              (fn [communities]
                  
                ;; here you can see the actual view/html (React components)
                [:ul
                 
                   ;; local data means functional transforms using the usual apis like map
                   (map (fn [[k community]]
                            
                          ;; with arbitrarily more hypercrud data resolutions
                          [hypercrud/resolve client community
                           ;; and arbitrarily more sub-views
                           (fn [community]
                             [:li (-> community :data :community/name)])])
                        (-> communities :data))])]))])