Merge "Permit plugins to implement AllRequestFilter"

gerrit-httpd/src/main/java/com/google/gerrit/httpd/AllRequestFilter.java

@@ -0,0 +1,86 @@
+// Copyright (C) 2012 The Android Open Source Project
+//
+// 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 com.google.gerrit.httpd;
+
+import com.google.gerrit.extensions.registration.DynamicSet;
+import com.google.inject.Inject;
+import com.google.inject.Singleton;
+import com.google.inject.servlet.ServletModule;
+
+import java.io.IOException;
+import java.util.Iterator;
+
+import javax.servlet.Filter;
+import javax.servlet.FilterChain;
+import javax.servlet.FilterConfig;
+import javax.servlet.ServletException;
+import javax.servlet.ServletRequest;
+import javax.servlet.ServletResponse;
+
+/** Filters all HTTP requests passing through the server. */
+public abstract class AllRequestFilter implements Filter {
+  public static ServletModule module() {
+    return new ServletModule() {
+      @Override
+      protected void configureServlets() {
+        DynamicSet.setOf(binder(), AllRequestFilter.class);
+        filter("/*").through(FilterProxy.class);
+      }
+    };
+  }
+
+  @Singleton
+  static class FilterProxy implements Filter {
+    private final DynamicSet<AllRequestFilter> filters;
+
+    @Inject
+    FilterProxy(DynamicSet<AllRequestFilter> filters) {
+      this.filters = filters;
+    }
+
+    @Override
+    public void doFilter(ServletRequest req, ServletResponse res,
+        final FilterChain last) throws IOException, ServletException {
+      final Iterator<AllRequestFilter> itr = filters.iterator();
+      new FilterChain() {
+        @Override
+        public void doFilter(ServletRequest req, ServletResponse res)
+            throws IOException, ServletException {
+          if (itr.hasNext()) {
+            itr.next().doFilter(req, res, this);
+          } else {
+            last.doFilter(req, res);
+          }
+        }
+      }.doFilter(req, res);
+    }
+
+    @Override
+    public void init(FilterConfig config) throws ServletException {
+    }
+
+    @Override
+    public void destroy() {
+    }
+  }
+
+  @Override
+  public void init(FilterConfig config) throws ServletException {
+  }
+
+  @Override
+  public void destroy() {
+  }
+}

gerrit-pgm/src/main/java/com/google/gerrit/pgm/Daemon.java

@@ -17,6 +17,7 @@ package com.google.gerrit.pgm;
 import static com.google.gerrit.server.schema.DataSourceProvider.Context.MULTI_USER;
 
 import com.google.gerrit.common.ChangeHookRunner;
+import com.google.gerrit.httpd.AllRequestFilter;
 import com.google.gerrit.httpd.CacheBasedWebSession;
 import com.google.gerrit.httpd.GitOverHttpModule;
 import com.google.gerrit.httpd.HttpCanonicalWebUrlProvider;
@@ -354,6 +355,7 @@ public class Daemon extends SiteProgram {
   private Injector createWebInjector() {
     final List<Module> modules = new ArrayList<Module>();
     modules.add(RequestContextFilter.module());
+    modules.add(AllRequestFilter.module());
     modules.add(CacheBasedWebSession.module());
     modules.add(HttpContactStoreConnection.module());
     modules.add(sysInjector.getInstance(GitOverHttpModule.class));

gerrit-war/src/main/java/com/google/gerrit/httpd/WebAppInitializer.java

@@ -224,6 +224,7 @@ public class WebAppInitializer extends GuiceServletContextListener {
   private Injector createWebInjector() {
     final List<Module> modules = new ArrayList<Module>();
     modules.add(RequestContextFilter.module());
+    modules.add(AllRequestFilter.module());
     modules.add(sysInjector.getInstance(GitOverHttpModule.class));
     modules.add(sshInjector.getInstance(WebModule.class));
     modules.add(sshInjector.getInstance(WebSshGlueModule.class));