add various clojurescript utility functions

project.clj

@@ -4,8 +4,19 @@
   :license     {:name "MIT License"
                 :url  "http://opensource.org/licenses/MIT"}
 
-  :dependencies [[org.clojure/clojure "1.8.0"]
-                 [compojure "1.4.0" :scope "provided"]
-                 [ring/ring-core "1.4.0" :scope "provided"]
-                 [cheshire "5.5.0"]
-                 [prismatic/schema "1.0.4"]])
+  :dependencies [[cheshire "5.5.0"]
+                 [prismatic/schema "1.0.4"]
+                 [cljs-ajax "0.5.5"]
+                 [secretary "1.2.3"]]
+
+  :plugins      [[lein-cljsbuild "1.1.3"]]
+
+  :profiles     {:provided
+                 {:dependencies [[org.clojure/clojure "1.8.0"]
+                                 [org.clojure/clojurescript "1.8.51"]
+                                 [compojure "1.4.0"]
+                                 [ring/ring-core "1.4.0"]]}}
+
+  :cljsbuild    {:builds
+                 {:main
+                  {:source-paths ["src"]}}})

src/webtools/cljs/ajax.cljs

@@ -0,0 +1,62 @@
+(ns webtools.cljs.ajax
+  (:require
+    [clojure.walk :refer [stringify-keys keywordize-keys]]
+    [ajax.core :as ajax]
+    [webtools.cljs.utils :refer [->url get-anti-forgery-token]]))
+
+(defn add-headers!
+  [headers]
+  (let [headers     (stringify-keys headers)
+        interceptor (ajax/to-interceptor
+                      {:request #(assoc % :headers (merge (:headers %) headers))})]
+    (swap! ajax/default-interceptors (partial cons interceptor))
+    headers))
+
+(defn add-csrf-header!
+  []
+  (let [token (get-anti-forgery-token)]
+    (if token (add-headers! {"X-CSRF-Token" token}))
+    token))
+
+(defn GET
+  [url & {:keys [format params on-success on-error on-complete keywords? headers]}]
+  (let [url   (->url url)
+        json? (or (= :json format)
+                  (nil? format))]
+    (ajax/GET url
+              (merge
+                {:format (or format :json)}
+                (if json? {:keywords? (or keywords? true)})
+                (if params {:params params})
+                (if headers {:headers (stringify-keys headers)})
+                (if on-success {:handler on-success})
+                (if on-error {:error-handler on-error})
+                (if on-complete {:finally on-complete})
+                ))))
+
+(defn POST
+  [url & {:keys [format params body on-success on-error on-complete keywords? headers]}]
+  (let [url   (->url url)
+        json? (or (= :json format)
+                  (nil? format))]
+    (ajax/POST url
+               (merge
+                 {:format (or format :json)}
+                 (if json? {:keywords? (or keywords? true)})
+                 (if params {:params params})
+                 (if body {:body body})
+                 (if headers {:headers (stringify-keys headers)})
+                 (if on-success {:handler on-success})
+                 (if on-error {:error-handler on-error})
+                 (if on-complete {:finally on-complete})))))
+
+(defn fetch!
+  [destination-atom url & {:keys [format params keywords? on-error headers transform]}]
+  (let [transform (or transform identity)]
+    (GET url
+         :format format
+         :params params
+         :keywords? keywords?
+         :on-error on-error
+         :headers headers
+         :on-success #(reset! destination-atom (transform %)))))

src/webtools/cljs/dom.cljs

@@ -0,0 +1,25 @@
+(ns webtools.cljs.dom)
+
+(defn element-by-id
+  [id]
+  (.getElementById js/document id))
+
+(defn select-all-elements
+  [selector]
+  (vec (.querySelectorAll js/document selector)))
+
+(defn select-element
+  [selector]
+  (.querySelector js/document selector))
+
+(defn get-metatag-content
+  [metatag-name]
+  (if-let [tag (select-element (str "meta[name='" metatag-name "']"))]
+    (.-content tag)))
+
+(defn has-class?
+  [element class-name]
+  (if (.-classList element)
+    (.contains (.-classList element) class-name)
+    (doto (js/RegExp. (str "(^| )" class-name "( |$)") "gi")
+      (.test (.-className element)))))

src/webtools/cljs/utils.cljs

@@ -0,0 +1,74 @@
+(ns webtools.cljs.utils
+  (:import
+    goog.History)
+  (:require
+    [clojure.string :as string]
+    [clojure.walk :refer [keywordize-keys]]
+    [goog.events :as events]
+    [goog.history.EventType :as EventType]
+    [secretary.core :as secretary]
+    [webtools.cljs.dom :as dom]))
+
+(defn- get-hidden-field-value
+  [hidden-field-id]
+  (if-let [hidden-field (dom/element-by-id hidden-field-id)]
+    (.-value hidden-field)))
+
+(defn get-anti-forgery-token
+  []
+  ; bunch of common names for this csrf token that i've seen used
+  ; ring's own anti-forgery middleware has a helper which outputs
+  ; an <input type="hidden"> with the id "__anti-forgery-token"
+  (->> [(dom/get-metatag-content "anti-forgery-token")
+        (dom/get-metatag-content "__anti-forgery-token")
+        (dom/get-metatag-content "csrf-token")
+        (get-hidden-field-value "anti-forgery-token")
+        (get-hidden-field-value "__anti-forgery-token")
+        (get-hidden-field-value "csrf-token")]
+       (remove nil?)
+       (first)))
+
+(defn dev?
+  []
+  (if (undefined? js/__isDev)
+    false
+    (boolean js/__isDev)))
+
+(defn context-url
+  []
+  (if (undefined? js/__context)
+    ""
+    (str js/__context)))
+
+(defn supports-websockets?
+  []
+  (not (-> (dom/select-element "html")
+           (dom/has-class? "no-websockets"))))
+
+(defn old-ie?
+  []
+  (-> (dom/select-element "html")
+      (dom/has-class? "old-ie")))
+
+(defn ->url
+  [url]
+  (-> (str (context-url) url)
+      (string/replace #"(/+)" "/")))
+
+(defn hook-browser-navigation!
+  []
+  (doto (History.)
+    (events/listen
+      EventType/NAVIGATE
+      (fn [event]
+        (secretary/dispatch! (.-token event))))
+    (.setEnabled true)))
+
+(defn redirect!
+  [secretary-url]
+  (-> (.-location js/window)
+      (set! secretary-url)))
+
+(defn pprint-json
+  [x]
+  (.stringify js/JSON (clj->js x) nil "  "))