Added observable for web worker communication

material/base.html

@@ -197,7 +197,7 @@
       {% endblock %}
     </div>
     {% block scripts %}
-      <script src="{{ 'assets/javascripts/app.js' | url }}"></script>
+      <script src="{{ 'assets/javascripts/bundle.js' | url }}"></script>
       {% if lang.t("search.language") != "en" %}
         {% set languages = lang.t("search.language").split(",") %}
         {% if languages | length and languages[0] != "" %}
@@ -235,7 +235,7 @@
         {%- endfor -%}
         {{ translations | tojson }}
       </script>
-      <script>app=initialize({base:"{{ base_url }}"})</script>
+      <script>app=initialize({base:"{{ base_url }}",search:"{{ 'assets/javascripts/search.js' | url }}"})</script>
       {% for path in config["extra_javascript"] %}
         <script src="{{ path | url }}"></script>
       {% endfor %}

package.json

@@ -68,8 +68,7 @@
     "tslint-sonarts": "^1.9.0",
     "typescript": "^3.6.3",
     "webpack": "^4.41.0",
-    "webpack-cli": "^3.3.9",
-    "worker-loader": "^2.0.0"
+    "webpack-cli": "^3.3.9"
   },
   "engines": {
     "node": ">= 10"

src/assets/javascripts/config/index.ts

@@ -29,6 +29,7 @@
  */
 export interface Config {
   base: string                         /* Base URL */
+  search: string                       /* Web worker URL */
 }
 
 /* ----------------------------------------------------------------------------

src/assets/javascripts/ui/worker/index.ts

@@ -0,0 +1,96 @@
+/*
+ * Copyright (c) 2016-2019 Martin Donath <martin.donath@squidfunk.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+import { Observable, fromEvent } from "rxjs"
+import {
+  pluck,
+  shareReplay,
+  switchMap,
+  take,
+  tap,
+  throttle
+} from "rxjs/operators"
+
+/* ----------------------------------------------------------------------------
+ * Types
+ * ------------------------------------------------------------------------- */
+
+/**
+ * Worker message
+ */
+export interface WorkerMessage {
+  type: unknown                        /* Message type */
+  data: unknown                        /* Message data */
+}
+
+/* ----------------------------------------------------------------------------
+ * Function types
+ * ------------------------------------------------------------------------- */
+
+/**
+ * Options
+ *
+ * @template T - Worker message type
+ */
+interface Options<T extends WorkerMessage> {
+  message$: Observable<T>              /* Message observable */
+}
+
+/* ----------------------------------------------------------------------------
+ * Functions
+ * ------------------------------------------------------------------------- */
+
+/**
+ * Watch a web worker
+ *
+ * This function returns an observable that will send all values emitted by the
+ * message observable to the web worker. Web worker communication is expected
+ * to be bidirectional (request-response) and synchronous. Messages that are
+ * emitted during a pending request are throttled, the last one is emitted.
+ *
+ * @param worker - Web worker
+ *
+ * @return Worker message observable
+ */
+export function watchWorker<T extends WorkerMessage>(
+  worker: Worker, { message$ }: Options<T>
+): Observable<T> {
+
+  /* Receive messages from web worker */
+  const worker$ = fromEvent(worker, "message")
+    .pipe(
+      pluck<Event, T>("data")
+    )
+
+  /* Send request and wait for response */
+  return message$
+    .pipe(
+      throttle(() => worker$, { leading: true, trailing: true }),
+      tap(message => worker.postMessage(message)),
+      switchMap(() => worker$
+        .pipe(
+          take(1)
+        )
+      ),
+      shareReplay(1)
+    )
+}

src/base.html

@@ -395,7 +395,7 @@
 
     <!-- Theme-related JavaScript -->
     {% block scripts %}
-      <script src="{{ 'assets/javascripts/app.js' | url }}"></script>
+      <script src="{{ 'assets/javascripts/bundle.js' | url }}"></script>
 
       <!-- Load additional languages for search -->
       {% if lang.t("search.language") != "en" %}
@@ -442,7 +442,8 @@
       <!-- Application initialization -->
       <script>
         app = initialize({
-          base: "{{ base_url }}"
+          base: "{{ base_url }}",
+          search: "{{ 'assets/javascripts/search.js' | url }}"
         });
       </script>
 

tsconfig.json

@@ -8,7 +8,8 @@
     "lib": [
       "dom",
       "es2017",
-      "esnext"
+      "esnext",
+      "webworker"
     ],
     "module": "commonjs",
     "moduleResolution": "node",

webpack.config.ts

@@ -21,28 +21,23 @@
  */
 
 import * as path from "path"
-// import { Options } from "ts-loader"
 import { Configuration } from "webpack"
 
 /* ----------------------------------------------------------------------------
- * Configuration
+ * Helper functions
  * ------------------------------------------------------------------------- */
 
 /**
- * Webpack configuration
+ * Webpack base configuration
  *
- * @param env - Webpack environment arguments
  * @param args - Command-line arguments
  *
  * @return Webpack configuration
  */
-export default (_env: never, args: Configuration) => {
+function config(args: Configuration): Configuration {
   return {
     mode: args.mode,
 
-    /* Entrypoint */
-    entry: ["src/assets/javascripts/index.ts"],
-
     /* Loaders */
     module: {
       rules: [
@@ -57,43 +52,14 @@ export default (_env: never, args: Configuration) => {
                 transpileOnly: true,
                 compilerOptions: {
                   module: "esnext",
-                  noUnusedLocals: args.mode === "production",
-                  noUnusedParameters: args.mode === "production",
                   removeComments: false
                 }
               }
             }
           ],
           exclude: /\/node_modules\//
-        },
-
-        {
-          test: /\worker\/(.*?)\.ts$/,
-          use: [
-            { loader: "worker-loader", options: {
-              inline: true, fallback: false            } },
-            {
-              loader: "ts-loader",
-              options: {
-                transpileOnly: true,
-                compilerOptions: {
-                  module: "esnext",
-                  noUnusedLocals: args.mode === "production",
-                  noUnusedParameters: args.mode === "production",     // TODO: do not duplicate
-                  removeComments: false
-                }
-              }
         }
       ]
-        }
-      ]
-    },
-
-    /* Export class constructor as entrypoint */
-    output: {
-      path: path.resolve(__dirname, "material/assets/javascripts"),
-      filename: "app.js",
-      libraryTarget: "window"
     },
 
     /* Module resolver */
@@ -109,3 +75,40 @@ export default (_env: never, args: Configuration) => {
     devtool: "source-map"
   }
 }
+
+/* ----------------------------------------------------------------------------
+ * Configuration
+ * ------------------------------------------------------------------------- */
+
+/**
+ * Webpack configuration
+ *
+ * @param env - Webpack environment arguments
+ * @param args - Command-line arguments
+ *
+ * @return Webpack configuration
+ */
+export default (_env: never, args: Configuration): Configuration[] => ([
+
+  /* Application */
+  {
+    ...config(args),
+    entry: "src/assets/javascripts",
+    output: {
+      path: path.resolve(__dirname, "material/assets/javascripts"),
+      filename: "bundle.js",
+      libraryTarget: "window"
+    }
+  },
+
+  /* Search worker */
+  {
+    ...config(args),
+    entry: "src/assets/javascripts/workers/search",
+    output: {
+      path: path.resolve(__dirname, "material/assets/javascripts"),
+      filename: "search.js",
+      libraryTarget: "var"
+    }
+  }
+])