Added support to serve the user interface from the 'ui/' directory of…

… the resources. Fixes #113. (#114)

swim-java/swim-runtime/swim-host/swim.service.web/src/main/java/swim/service/web/UiRouter.java

@@ -0,0 +1,101 @@
+// Copyright 2015-2022 Swim.inc
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package swim.service.web;
+
+import swim.kernel.KernelProxy;
+import swim.structure.Value;
+import swim.uri.UriPath;
+import swim.web.WebRequest;
+import swim.web.WebResponse;
+import swim.web.WebRoute;
+import swim.web.route.ResourceDirectoryRoute;
+
+/**
+ * SwimOS kernel module for routing HTTP requests for the bundled UI.
+ */
+public class UiRouter extends KernelProxy {
+  final double kernelPriority;
+  final WebRoute uiRoute;
+
+  public UiRouter(double kernelPriority) {
+    this.kernelPriority = kernelPriority;
+    this.uiRoute = new ResourceDirectoryRoute(getClass().getClassLoader(), UriPath.parse("ui/"), "index.html");
+  }
+
+  public UiRouter() {
+    this(KERNEL_PRIORITY);
+  }
+
+  @Override
+  public final double kernelPriority() {
+    return this.kernelPriority;
+  }
+
+  @Override
+  public WebResponse routeRequest(WebRequest request) {
+    final WebResponse response = this.uiRoute.routeRequest(request);
+    if (response.isAccepted()) {
+      return response;
+    } else {
+      return super.routeRequest(request);
+    }
+  }
+
+  @Override
+  public void trace(Object message) {
+    // Use this hook to intercept and forward trace log messages
+  }
+
+  @Override
+  public void debug(Object message) {
+    // Use this hook to intercept and forward debug log messages
+  }
+
+  @Override
+  public void info(Object message) {
+    super.info(message);
+    // Use this hook to intercept and forward info log messages
+  }
+
+  @Override
+  public void warn(Object message) {
+    super.warn(message);
+    // Use this hook to intercept and forward warning log messages
+  }
+
+  @Override
+  public void error(Object message) {
+    super.error(message);
+    // Use this hook to intercept and forward error log messages
+  }
+
+  @Override
+  public void fail(Object message) {
+    super.fail(message);
+    // Use this hook to intercept and forward failure log messages
+  }
+
+  private static final double KERNEL_PRIORITY = 100.0;
+
+  public static UiRouter fromValue(Value moduleConfig) {
+    final Value header = moduleConfig.getAttr("kernel");
+    final String kernelClassName = header.get("class").stringValue(null);
+    if (kernelClassName == null || UiRouter.class.getName().equals(kernelClassName)) {
+      final double kernelPriority = header.get("priority").doubleValue(KERNEL_PRIORITY);
+      return new UiRouter(kernelPriority);
+    }
+    return null;
+  }
+}