Implement StalenessChecker for projects

This commit implements a staleness checker for projects in the same
fashion that we have it for groups and accounts. It uses the newly added
ref_state field.

Change-Id: Icbcf0bd1c700df789ef26501e4218956d718ea4c

java/com/google/gerrit/acceptance/AbstractDaemonTest.java

@@ -68,6 +68,8 @@ import com.google.gerrit.extensions.common.EditInfo;
 import com.google.gerrit.extensions.restapi.BinaryResult;
 import com.google.gerrit.extensions.restapi.IdString;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.index.project.ProjectIndex;
+import com.google.gerrit.index.project.ProjectIndexCollection;
 import com.google.gerrit.mail.Address;
 import com.google.gerrit.mail.EmailHeader;
 import com.google.gerrit.reviewdb.client.Account;
@@ -274,6 +276,7 @@ public abstract class AbstractDaemonTest {
 
   @Inject private ChangeIndexCollection changeIndexes;
   @Inject private AccountIndexCollection accountIndexes;
+  @Inject private ProjectIndexCollection projectIndexes;
   @Inject private EventRecorder.Factory eventRecorderFactory;
   @Inject private InProcessProtocol inProcessProtocol;
   @Inject private Provider<AnonymousUser> anonymousUser;
@@ -900,6 +903,41 @@ public abstract class AbstractDaemonTest {
     };
   }
 
+  protected AutoCloseable disableProjectIndex() {
+    disableProjectIndexWrites();
+    ProjectIndex searchIndex = projectIndexes.getSearchIndex();
+    if (!(searchIndex instanceof DisabledProjectIndex)) {
+      projectIndexes.setSearchIndex(new DisabledProjectIndex(searchIndex), false);
+    }
+
+    return new AutoCloseable() {
+      @Override
+      public void close() {
+        enableProjectIndexWrites();
+        ProjectIndex searchIndex = projectIndexes.getSearchIndex();
+        if (searchIndex instanceof DisabledProjectIndex) {
+          projectIndexes.setSearchIndex(((DisabledProjectIndex) searchIndex).unwrap(), false);
+        }
+      }
+    };
+  }
+
+  protected void disableProjectIndexWrites() {
+    for (ProjectIndex i : projectIndexes.getWriteIndexes()) {
+      if (!(i instanceof DisabledProjectIndex)) {
+        projectIndexes.addWriteIndex(new DisabledProjectIndex(i));
+      }
+    }
+  }
+
+  protected void enableProjectIndexWrites() {
+    for (ProjectIndex i : projectIndexes.getWriteIndexes()) {
+      if (i instanceof DisabledProjectIndex) {
+        projectIndexes.addWriteIndex(((DisabledProjectIndex) i).unwrap());
+      }
+    }
+  }
+
   protected static Gson newGson() {
     return OutputFormat.JSON_COMPACT.newGson();
   }

java/com/google/gerrit/acceptance/BUILD

@@ -99,6 +99,7 @@ java_library2(
         "//java/com/google/gerrit/extensions:api",
         "//java/com/google/gerrit/httpd",
         "//java/com/google/gerrit/index",
+        "//java/com/google/gerrit/index/project",
         "//java/com/google/gerrit/lucene",
         "//java/com/google/gerrit/mail",
         "//java/com/google/gerrit/metrics",

java/com/google/gerrit/acceptance/DisabledProjectIndex.java

@@ -0,0 +1,76 @@
+// Copyright (C) 2018 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.acceptance;
+
+import com.google.gerrit.index.QueryOptions;
+import com.google.gerrit.index.Schema;
+import com.google.gerrit.index.project.ProjectData;
+import com.google.gerrit.index.project.ProjectIndex;
+import com.google.gerrit.index.query.DataSource;
+import com.google.gerrit.index.query.Predicate;
+import com.google.gerrit.reviewdb.client.Project;
+
+/**
+ * This class wraps an index and assumes the search index can't handle any queries. However, it does
+ * return the current schema as the assumption is that we need a search index for starting Gerrit in
+ * the first place and only later lose the index connection (making it so that we can't send
+ * requests there anymore).
+ */
+public class DisabledProjectIndex implements ProjectIndex {
+  private final ProjectIndex index;
+
+  public DisabledProjectIndex(ProjectIndex index) {
+    this.index = index;
+  }
+
+  public ProjectIndex unwrap() {
+    return index;
+  }
+
+  @Override
+  public Schema<ProjectData> getSchema() {
+    return index.getSchema();
+  }
+
+  @Override
+  public void close() {
+    index.close();
+  }
+
+  @Override
+  public void replace(ProjectData obj) {
+    throw new UnsupportedOperationException("ProjectIndex is disabled");
+  }
+
+  @Override
+  public void delete(Project.NameKey key) {
+    throw new UnsupportedOperationException("ProjectIndex is disabled");
+  }
+
+  @Override
+  public void deleteAll() {
+    throw new UnsupportedOperationException("ProjectIndex is disabled");
+  }
+
+  @Override
+  public DataSource<ProjectData> getSource(Predicate<ProjectData> p, QueryOptions opts) {
+    throw new UnsupportedOperationException("ProjectIndex is disabled");
+  }
+
+  @Override
+  public void markReady(boolean ready) {
+    throw new UnsupportedOperationException("ProjectIndex is disabled");
+  }
+}