Better java.time support.

src/tech/v3/libs/cljs_ajax.cljs

@@ -4,33 +4,61 @@
             [ajax.interceptors :as ajax-interceptors]
             [ajax.transit :as ajax-transit]
             [tech.v3.dataset :as ds]
-            [cognitect.transit :as transit]))
+            [tech.v3.datatype.datetime :as dtype-dt]
+            [java.time :refer [LocalDate Instant]]
+            [cognitect.transit :as t]))
 
 
-(def ^{:doc "Transit writer used for writing transit-json datasets and uses
-`ds/transit-write-handler-map`" }
-  writer (transit/writer :json {:handlers (ds/transit-write-handler-map)}))
+(defonce write-handlers* (atom (ds/transit-write-handler-map)))
+(defonce read-handlers* (atom (ds/transit-read-handler-map)))
 
 
-(def ^{:doc "cljs-ajax interceptor that hardwires content-type to application/transit+json
-and uses `ds/transit-read-handler-map`." }
-  response-format
+(defn add-transit-io-handlers!
+  [datatype tag read-fn write-fn]
+  (swap! write-handlers* assoc datatype (t/write-handler (constantly tag) write-fn))
+  (swap! read-handlers* assoc tag read-fn))
+
+
+(defn add-java-time-handlers!
+  "Add handlers for java.time.LocalDate and java.time.Instant"
+  []
+  (add-transit-io-handlers! LocalDate "java.time.LocalDate"
+                            dtype-dt/epoch-days->local-date
+                            dtype-dt/local-date->epoch-days)
+  (add-transit-io-handlers! Instant "java.time.Instant"
+                            dtype-dt/epoch-milliseconds->instant
+                            dtype-dt/instant->epoch-milliseconds))
+
+
+(defn writer
+  "Transit writer used for writing transit-json datasets and uses
+`ds/transit-write-handler-map`"
+  []
+  (t/writer :json {:handlers @write-handlers*}))
+
+
+(defn response-format
+  "cljs-ajax interceptor that hardwires content-type to application/transit+json
+  and uses `ds/transit-read-handler-map`."
+  [& [content-type]]
   (ajax-interceptors/map->ResponseFormat
-   {:content-type ["application/transit+json"]
+   {:content-type (or content-type ["application/transit+json"])
     :description "Transit response"
-    :read (ajax-transit/transit-read-fn {:handlers (ds/transit-read-handler-map)})}))
+    :read (ajax-transit/transit-read-fn {:handlers @read-handlers*})}))
 
 
-(def ^{:doc "Options map that must be included in the cljs-ajax request in order
-to activate dataset->transit pathways."} opt-map
-  {:writer writer :response-format response-format})
+(defn opt-map
+  "Options map that must be included in the cljs-ajax request in order
+  to activate dataset->transit pathways."
+  []
+  {:writer (writer) :response-format (response-format)})
 
 
 (defn transit-request
   "Perform a cljs-ajax request using the select cljs-ajax.core method and merging
   [[opt-map]] first into the options."
   [method url options]
-  (method url (merge opt-map options)))
+  (method url (merge (opt-map) options)))
 
 
 (defn GET

src/tech/v3/libs/muuntaja.clj

@@ -39,3 +39,11 @@
   * `:read-handlers` - transit handler-map of extra handlers to use when reading data."
   [handler & [options]]
   (muuntaja-middle/wrap-format handler (muuntaja options)))
+
+
+(defn wrap-format-java-time
+  "Wrap-format support datasets and scalar java.time.LocalDate and java.time.Instant objects."
+  [handler & [options]]
+  (wrap-format handler (assoc options
+                              :write-handlers tech-transit/java-time-write-handlers
+                              :read-handlers tech-transit/java-time-read-handlers)))

src/tech/v3/libs/transit.clj

@@ -15,7 +15,8 @@
   (:import [tech.v3.dataset.impl.dataset Dataset]
            [tech.v3.dataset.impl.column Column]
            [java.nio ByteBuffer ByteOrder]
-           [java.util Base64 HashMap]))
+           [java.util Base64 HashMap]
+           [java.time LocalDate Instant]))
 
 (set! *warn-on-reflection* true)
 
@@ -204,6 +205,15 @@
 (def write-handlers {Dataset (t/write-handler "tech.v3.dataset" dataset->data)})
 (def read-handlers {"tech.v3.dataset" (t/read-handler data->dataset)})
 
+(def java-time-write-handlers
+  {LocalDate (t/write-handler "java.time.LocalDate" dtype-dt/local-date->days-since-epoch)
+   Instant (t/write-handler "java.time.Instant" dtype-dt/instant->milliseconds-since-epoch)})
+
+(def java-time-read-handlers
+  {"java.time.LocalDate" dtype-dt/days-since-epoch->local-date
+   "java.time.Instant" dtype-dt/milliseconds-since-epoch->instant})
+
+
 (defn dataset->transit
   "Convert a dataset into transit"
   [ds out & [format handlers]]

testapp/deps.edn

@@ -1,5 +1,5 @@
 {:paths ["src" "resources"]
- :deps {com.cnuernber/tmdjs {:mvn/version "1.000-beta-6"}
+ :deps {com.cnuernber/tmdjs {:mvn/version "1.000-beta-15-SNAPSHOT"}
         http-kit/http-kit {:mvn/version "2.5.3"}
         hiccup/hiccup {:mvn/version"1.0.5"}
         bidi/bidi {:mvn/version "2.1.6"}

testapp/src/testapp/main.clj

@@ -5,12 +5,14 @@
             [ring.middleware.resource :refer [wrap-resource]]
             [ring.middleware.content-type :refer [wrap-content-type]]
             ;;automatic handling of transit->dataset conversion
-            [tech.v3.libs.muuntaja :refer [wrap-format]]
+            [tech.v3.libs.muuntaja :refer [wrap-format-java-time]]
             [ring.middleware.cookies :refer [wrap-cookies]]
             [ring.middleware.gzip :refer [wrap-gzip]]
             [bidi.ring :as bidi-ring]
             [clojure.tools.logging :as log]
-            [tech.v3.dataset :as ds])
+            [tech.v3.dataset :as ds]
+            [tech.v3.libs.transit :as tech-transit])
+  (:import [java.time LocalDate Instant])
   (:gen-class))
 
 
@@ -46,6 +48,12 @@
       (response/response)))
 
 
+(defn datetest
+  [request]
+  (response/response {:local-date (LocalDate/now)
+                      :instant (Instant/now)}))
+
+
 (defn stocks-data
   [request]
   (-> (ds/->dataset "https://github.com/techascent/tech.ml.dataset/raw/master/test/data/stocks.csv" {:key-fn keyword})
@@ -54,12 +62,14 @@
 
 (def routes ["/" {:get [["data" #'generate-data]
                         ["stocks" #'stocks-data]
+                        ["datetest" #'datetest]
                         [true #'home-page]]}])
 
 (defn handler
   []
   (-> (bidi-ring/make-handler routes)
-      (wrap-format)
+      (wrap-format-java-time {:write-handlers tech-transit/java-time-write-handlers
+                              :read-handlers tech-transit/java-time-read-handlers})
       (wrap-cookies)
       (wrap-resource "public")
       (wrap-content-type)

testapp/src/testapp/webapp.cljs

@@ -2,10 +2,11 @@
   (:require [goog.dom :as gdom]
             [reagent.dom]
             [reagent.ratom :refer [atom]]
-            [tech.v3.libs.cljs-ajax :refer [GET POST]]
+            [tech.v3.libs.cljs-ajax :refer [GET POST] :as tech-cljs-ajax]
             [tech.v3.dataset :as ds]
             [tech.v3.datatype.functional :as dfn]))
 
+
 (defonce app* (atom {}))
 
 
@@ -71,4 +72,6 @@
 (defn init
   "Entrypoint into the application."
   []
+  (tech-cljs-ajax/add-java-time-handlers!)
+
   (render))