✨ Integrate svgclean and graal-js to svgparse service.

backend/src/app/svgparse.clj

@@ -17,67 +17,127 @@
    [clojure.java.shell :as shell]
    [clojure.spec.alpha :as s]
    [clojure.xml :as xml]
+   [app.util.graal :as graal]
+   [app.util.pool :as pool]
    [integrant.core :as ig])
   (:import
    java.io.InputStream
+   java.util.function.Consumer
    org.apache.commons.io.IOUtils))
 
-(defn- string->input-stream
-  [^String data]
-  (IOUtils/toInputStream data "UTF-8"))
+;; (defn- clean-svg
+;;   [^InputStream input]
+;;   (let [result (shell/sh
+;;                 ;; "svgcleaner" "--allow-bigger-file" "-c" "-"
+;;                 "svgo"
+;;                 "--enable=prefixIds,removeDimensions,removeXMLNS,removeScriptElement"
+;;                 "--disable=removeViewBox,moveElemsAttrsToGroup"
+;;                 "-i" "-" "-o" "-"
 
-(defn- stream->string
-  [input]
-  (with-open [istream (io/input-stream input)]
-    (-> (IOUtils/toString input "UTF-8"))))
+;;                 :in input :out-enc :bytes)
+;;         err-str (:err result)]
+;;     (when (or (not= 0 (:exit result))
+;;               ;; svgcleaner returns 0 with some errors, we need to check
+;;               (and (not= err-str "") (not (nil? err-str)) (str/starts-with? err-str "Error")))
+;;       (ex/raise :type :validation
+;;                 :code :unable-to-optimize
+;;                 :hint (:err result)))
+;;     (io/input-stream (:out result))))
 
-(defn- clean-svg
-  [^InputStream input]
-  (let [result (shell/sh
-                ;; "svgcleaner" "--allow-bigger-file" "-c" "-"
-                "svgo"
-                "--enable=prefixIds,removeDimensions,removeXMLNS,removeScriptElement"
-                "--disable=removeViewBox,moveElemsAttrsToGroup"
-                "-i" "-" "-o" "-"
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; SVG Clean
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
-                :in input :out-enc :bytes)
-        err-str (:err result)]
-    (when (or (not= 0 (:exit result))
-              ;; svgcleaner returns 0 with some errors, we need to check
-              (and (not= err-str "") (not (nil? err-str)) (str/starts-with? err-str "Error")))
-      (ex/raise :type :validation
-                :code :unable-to-optimize
-                :hint (:err result)))
-    (io/input-stream (:out result))))
+(declare do-svg-clean)
+(declare prepare-context-pool)
 
-(defn parse
-  [^InputStream input]
-  (with-open [istream (io/input-stream input)]
-    (-> (clean-svg istream)
-        (xml/parse))))
+(defmethod ig/pre-init-spec ::svgc [_]
+  (s/keys :req-un [::mtx/metrics]))
+
+(defmethod ig/init-key ::svgc
+  [_ {:keys [metrics] :as cfg}]
+  (let [ctx-pool (prepare-context-pool)]
+    (with-meta
+      (fn [data]
+        (with-open [ctx (pool/acquire ctx-pool)]
+          (do-svg-clean @ctx data)))
+      {::ctx-pool ctx-pool})))
+
+(defmethod ig/halt-key! ::svgc
+  [_ f]
+  (let [{:keys [::ctx-pool]} (meta f)]
+    (pool/clear! ctx-pool)
+    (pool/close! ctx-pool)))
+
+(defn- prepare-context-pool
+  []
+  (pool/create
+   {:min-idle 0
+    :max-idle 3
+    :max-total 3
+    :create
+    (fn []
+      (let [ctx (graal/context "js")]
+        (->> (graal/source "js" (io/resource "svgclean.js"))
+             (graal/eval! ctx))
+        ctx))
+    :destroy
+    (fn [ctx]
+      (graal/close! ctx))}))
+
+(defn- do-svg-clean
+  [ctx data]
+  (let [res     (promise)
+        cleaner (->> (graal/source "js" "require('svgclean')")
+                     (graal/eval! ctx))
+        resultp (graal/invoke-member cleaner "optimize" data)]
+    (graal/invoke-member resultp "then"
+                         (reify Consumer
+                           (accept [_ val]
+                             (deliver res val))))
+    (graal/invoke-member resultp "catch"
+                         (reify Consumer
+                           (accept [_ err]
+                             (deliver res err))))
+
+    (let [result (deref res)]
+      (if (instance? Throwable result)
+        (throw result)
+        result))))
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; Handler
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 (declare handler)
+(declare process-request)
+
+(s/def ::svgc fn?)
 
 (defmethod ig/pre-init-spec ::handler [_]
-  (s/keys :req-un [::mtx/metrics]))
+  (s/keys :req-un [::mtx/metrics ::svgc]))
 
 (defmethod ig/init-key ::handler
   [_ {:keys [metrics] :as cfg}]
-  (->> {:registry (:registry metrics)
-        :type :summary
-        :name "http_handler_svgparse_timing"
-        :help "svg parse timings"}
-       (mtx/instrument handler)))
+  (let [handler #(handler cfg %)]
+    (->> {:registry (:registry metrics)
+          :type :summary
+          :name "http_handler_svgparse_timing"
+          :help "svg parse timings"}
+         (mtx/instrument handler))))
 
 (defn- handler
-  [{:keys [headers body] :as request}]
+  [cfg {:keys [headers body] :as request}]
   (when (not= "image/svg+xml" (get headers "content-type"))
     (ex/raise :type :validation
               :code :unsupported-mime-type
               :mime (get headers "content-type")))
   {:status 200
-   :body (parse body)})
+   :body (process-request cfg body)})
+
+(defn process-request
+  [{:keys [svgc] :as cfg} body]
+  (let [data (slurp body)
+        data (svgc data)]
+    (with-open [istream (IOUtils/toInputStream data "UTF-8")]
+      (xml/parse istream))))