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diff --git a/java/com/google/gerrit/server/events/EventBroker.java b/java/com/google/gerrit/server/events/EventBroker.java
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+++ b/java/com/google/gerrit/server/events/EventBroker.java
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+// Copyright (C) 2016 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.server.events;
+
+import com.google.common.flogger.FluentLogger;
+import com.google.gerrit.extensions.registration.DynamicItem;
+import com.google.gerrit.extensions.restapi.AuthException;
+import com.google.gerrit.lifecycle.LifecycleModule;
+import com.google.gerrit.reviewdb.client.Branch;
+import com.google.gerrit.reviewdb.client.Change;
+import com.google.gerrit.reviewdb.client.PatchSet;
+import com.google.gerrit.reviewdb.client.Project;
+import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.server.CurrentUser;
+import com.google.gerrit.server.notedb.ChangeNotes;
+import com.google.gerrit.server.permissions.ChangePermission;
+import com.google.gerrit.server.permissions.PermissionBackend;
+import com.google.gerrit.server.permissions.PermissionBackendException;
+import com.google.gerrit.server.permissions.ProjectPermission;
+import com.google.gerrit.server.permissions.RefPermission;
+import com.google.gerrit.server.plugincontext.PluginSetContext;
+import com.google.gerrit.server.plugincontext.PluginSetEntryContext;
+import com.google.gerrit.server.project.NoSuchChangeException;
+import com.google.gerrit.server.project.ProjectCache;
+import com.google.gerrit.server.project.ProjectState;
+import com.google.gwtorm.server.OrmException;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+import com.google.inject.Singleton;
+
+/** Distributes Events to listeners if they are allowed to see them */
+@Singleton
+public class EventBroker implements EventDispatcher {
+  private static final FluentLogger logger = FluentLogger.forEnclosingClass();
+
+  public static class Module extends LifecycleModule {
+    @Override
+    protected void configure() {
+      DynamicItem.itemOf(binder(), EventDispatcher.class);
+      DynamicItem.bind(binder(), EventDispatcher.class).to(EventBroker.class);
+    }
+  }
+
+  /** Listeners to receive changes as they happen (limited by visibility of user). */
+  protected final PluginSetContext<UserScopedEventListener> listeners;
+
+  /** Listeners to receive all changes as they happen. */
+  protected final PluginSetContext<EventListener> unrestrictedListeners;
+
+  private final PermissionBackend permissionBackend;
+  protected final ProjectCache projectCache;
+
+  protected final ChangeNotes.Factory notesFactory;
+
+  protected final Provider<ReviewDb> dbProvider;
+
+  @Inject
+  public EventBroker(
+      PluginSetContext<UserScopedEventListener> listeners,
+      PluginSetContext<EventListener> unrestrictedListeners,
+      PermissionBackend permissionBackend,
+      ProjectCache projectCache,
+      ChangeNotes.Factory notesFactory,
+      Provider<ReviewDb> dbProvider) {
+    this.listeners = listeners;
+    this.unrestrictedListeners = unrestrictedListeners;
+    this.permissionBackend = permissionBackend;
+    this.projectCache = projectCache;
+    this.notesFactory = notesFactory;
+    this.dbProvider = dbProvider;
+  }
+
+  @Override
+  public void postEvent(Change change, ChangeEvent event)
+      throws OrmException, PermissionBackendException {
+    fireEvent(change, event);
+  }
+
+  @Override
+  public void postEvent(Branch.NameKey branchName, RefEvent event)
+      throws PermissionBackendException {
+    fireEvent(branchName, event);
+  }
+
+  @Override
+  public void postEvent(Project.NameKey projectName, ProjectEvent event) {
+    fireEvent(projectName, event);
+  }
+
+  @Override
+  public void postEvent(Event event) throws OrmException, PermissionBackendException {
+    fireEvent(event);
+  }
+
+  protected void fireEventForUnrestrictedListeners(Event event) {
+    unrestrictedListeners.runEach(l -> l.onEvent(event));
+  }
+
+  protected void fireEvent(Change change, ChangeEvent event)
+      throws OrmException, PermissionBackendException {
+    for (PluginSetEntryContext<UserScopedEventListener> c : listeners) {
+      CurrentUser user = c.call(l -> l.getUser());
+      if (isVisibleTo(change, user)) {
+        c.run(l -> l.onEvent(event));
+      }
+    }
+    fireEventForUnrestrictedListeners(event);
+  }
+
+  protected void fireEvent(Project.NameKey project, ProjectEvent event) {
+    for (PluginSetEntryContext<UserScopedEventListener> c : listeners) {
+      CurrentUser user = c.call(l -> l.getUser());
+      if (isVisibleTo(project, user)) {
+        c.run(l -> l.onEvent(event));
+      }
+    }
+    fireEventForUnrestrictedListeners(event);
+  }
+
+  protected void fireEvent(Branch.NameKey branchName, RefEvent event)
+      throws PermissionBackendException {
+    for (PluginSetEntryContext<UserScopedEventListener> c : listeners) {
+      CurrentUser user = c.call(l -> l.getUser());
+      if (isVisibleTo(branchName, user)) {
+        c.run(l -> l.onEvent(event));
+      }
+    }
+    fireEventForUnrestrictedListeners(event);
+  }
+
+  protected void fireEvent(Event event) throws OrmException, PermissionBackendException {
+    for (PluginSetEntryContext<UserScopedEventListener> c : listeners) {
+      CurrentUser user = c.call(l -> l.getUser());
+      if (isVisibleTo(event, user)) {
+        c.run(l -> l.onEvent(event));
+      }
+    }
+    fireEventForUnrestrictedListeners(event);
+  }
+
+  protected boolean isVisibleTo(Project.NameKey project, CurrentUser user) {
+    try {
+      ProjectState state = projectCache.get(project);
+      if (state == null || !state.statePermitsRead()) {
+        return false;
+      }
+
+      permissionBackend.user(user).project(project).check(ProjectPermission.ACCESS);
+      return true;
+    } catch (AuthException | PermissionBackendException e) {
+      return false;
+    }
+  }
+
+  protected boolean isVisibleTo(Change change, CurrentUser user)
+      throws OrmException, PermissionBackendException {
+    if (change == null) {
+      return false;
+    }
+    ProjectState pe = projectCache.get(change.getProject());
+    if (pe == null || !pe.statePermitsRead()) {
+      return false;
+    }
+    ReviewDb db = dbProvider.get();
+    try {
+      permissionBackend
+          .user(user)
+          .change(notesFactory.createChecked(db, change))
+          .database(db)
+          .check(ChangePermission.READ);
+      return true;
+    } catch (AuthException e) {
+      return false;
+    }
+  }
+
+  protected boolean isVisibleTo(Branch.NameKey branchName, CurrentUser user)
+      throws PermissionBackendException {
+    ProjectState pe = projectCache.get(branchName.getParentKey());
+    if (pe == null || !pe.statePermitsRead()) {
+      return false;
+    }
+
+    try {
+      permissionBackend.user(user).ref(branchName).check(RefPermission.READ);
+      return true;
+    } catch (AuthException e) {
+      return false;
+    }
+  }
+
+  protected boolean isVisibleTo(Event event, CurrentUser user)
+      throws OrmException, PermissionBackendException {
+    if (event instanceof RefEvent) {
+      RefEvent refEvent = (RefEvent) event;
+      String ref = refEvent.getRefName();
+      if (PatchSet.isChangeRef(ref)) {
+        Change.Id cid = PatchSet.Id.fromRef(ref).getParentKey();
+        try {
+          Change change =
+              notesFactory
+                  .createChecked(dbProvider.get(), refEvent.getProjectNameKey(), cid)
+                  .getChange();
+          return isVisibleTo(change, user);
+        } catch (NoSuchChangeException e) {
+          logger.atFine().log(
+              "Change %s cannot be found, falling back on ref visibility check", cid.id);
+        }
+      }
+      return isVisibleTo(refEvent.getBranchNameKey(), user);
+    } else if (event instanceof ProjectEvent) {
+      return isVisibleTo(((ProjectEvent) event).getProjectNameKey(), user);
+    }
+    return true;
+  }
+}