Java tutorial
// Copyright (C) 2014 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.index.change; import static com.google.common.util.concurrent.MoreExecutors.directExecutor; import static com.google.gerrit.server.query.change.ChangeData.asChanges; import com.google.common.util.concurrent.FutureCallback; import com.google.common.util.concurrent.Futures; import com.google.common.util.concurrent.ListeningExecutorService; import com.google.gerrit.extensions.events.GitReferenceUpdatedListener; import com.google.gerrit.reviewdb.client.Branch; import com.google.gerrit.reviewdb.client.Change; import com.google.gerrit.reviewdb.client.Project; import com.google.gerrit.reviewdb.client.RefNames; import com.google.gerrit.reviewdb.server.ReviewDb; import com.google.gerrit.server.config.GerritServerConfig; import com.google.gerrit.server.git.QueueProvider.QueueType; import com.google.gerrit.server.index.IndexExecutor; import com.google.gerrit.server.notedb.ChangeNotes; import com.google.gerrit.server.project.NoSuchChangeException; import com.google.gerrit.server.query.change.InternalChangeQuery; import com.google.gerrit.server.util.ManualRequestContext; import com.google.gerrit.server.util.OneOffRequestContext; import com.google.gerrit.server.util.RequestContext; import com.google.gwtorm.server.OrmException; import com.google.inject.Inject; import com.google.inject.Provider; import java.io.IOException; import java.util.List; import java.util.concurrent.Callable; import java.util.concurrent.Future; import org.eclipse.jgit.lib.Config; import org.slf4j.Logger; import org.slf4j.LoggerFactory; public class ReindexAfterRefUpdate implements GitReferenceUpdatedListener { private static final Logger log = LoggerFactory.getLogger(ReindexAfterRefUpdate.class); private final OneOffRequestContext requestContext; private final Provider<InternalChangeQuery> queryProvider; private final ChangeIndexer.Factory indexerFactory; private final ChangeIndexCollection indexes; private final ChangeNotes.Factory notesFactory; private final ListeningExecutorService executor; private final boolean enabled; @Inject ReindexAfterRefUpdate(@GerritServerConfig Config cfg, OneOffRequestContext requestContext, Provider<InternalChangeQuery> queryProvider, ChangeIndexer.Factory indexerFactory, ChangeIndexCollection indexes, ChangeNotes.Factory notesFactory, @IndexExecutor(QueueType.BATCH) ListeningExecutorService executor) { this.requestContext = requestContext; this.queryProvider = queryProvider; this.indexerFactory = indexerFactory; this.indexes = indexes; this.notesFactory = notesFactory; this.executor = executor; this.enabled = cfg.getBoolean("index", null, "reindexAfterRefUpdate", true); } @Override public void onGitReferenceUpdated(final Event event) { if (!enabled || event.getRefName().startsWith(RefNames.REFS_CHANGES) || event.getRefName().startsWith(RefNames.REFS_DRAFT_COMMENTS) || event.getRefName().startsWith(RefNames.REFS_USERS)) { return; } Futures.addCallback(executor.submit(new GetChanges(event)), new FutureCallback<List<Change>>() { @Override public void onSuccess(List<Change> changes) { for (Change c : changes) { // Don't retry indefinitely; if this fails changes may be stale. @SuppressWarnings("unused") Future<?> possiblyIgnoredError = executor.submit(new Index(event, c.getId())); } } @Override public void onFailure(Throwable ignored) { // Logged by {@link GetChanges#call()}. } }, directExecutor()); } private abstract class Task<V> implements Callable<V> { protected Event event; protected Task(Event event) { this.event = event; } @Override public final V call() throws Exception { try (ManualRequestContext ctx = requestContext.open()) { return impl(ctx); } catch (Exception e) { log.error("Failed to reindex changes after " + event, e); throw e; } } protected abstract V impl(RequestContext ctx) throws Exception; } private class GetChanges extends Task<List<Change>> { private GetChanges(Event event) { super(event); } @Override protected List<Change> impl(RequestContext ctx) throws OrmException { String ref = event.getRefName(); Project.NameKey project = new Project.NameKey(event.getProjectName()); if (ref.equals(RefNames.REFS_CONFIG)) { return asChanges(queryProvider.get().byProjectOpen(project)); } return asChanges(queryProvider.get().byBranchNew(new Branch.NameKey(project, ref))); } @Override public String toString() { return "Get changes to reindex caused by " + event.getRefName() + " update of project " + event.getProjectName(); } } private class Index extends Task<Void> { private final Change.Id id; Index(Event event, Change.Id id) { super(event); this.id = id; } @Override protected Void impl(RequestContext ctx) throws OrmException, IOException { // Reload change, as some time may have passed since GetChanges. ReviewDb db = ctx.getReviewDbProvider().get(); try { Change c = notesFactory.createChecked(db, new Project.NameKey(event.getProjectName()), id) .getChange(); indexerFactory.create(executor, indexes).index(db, c); } catch (NoSuchChangeException e) { indexerFactory.create(executor, indexes).delete(id); } return null; } @Override public String toString() { return "Index change " + id.get() + " of project " + event.getProjectName(); } } }