// Copyright (C) 2013 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;
import com.google.common.base.Function;
import com.google.common.util.concurrent.Atomics;
import com.google.common.util.concurrent.CheckedFuture;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListeningExecutorService;
import com.google.gerrit.reviewdb.client.Change;
import com.google.gerrit.reviewdb.server.ReviewDb;
import com.google.gerrit.server.CurrentUser;
import com.google.gerrit.server.query.change.ChangeData;
import com.google.gerrit.server.util.RequestContext;
import com.google.gerrit.server.util.ThreadLocalRequestContext;
import com.google.gwtorm.server.OrmException;
import com.google.gwtorm.server.SchemaFactory;
import com.google.inject.OutOfScopeException;
import com.google.inject.Provider;
import com.google.inject.ProvisionException;
import com.google.inject.assistedinject.Assisted;
import com.google.inject.assistedinject.AssistedInject;
import com.google.inject.util.Providers;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.IOException;
import java.util.Collection;
import java.util.Collections;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.atomic.AtomicReference;
/**
* Helper for (re)indexing a change document.
* <p>
* Indexing is run in the background, as it may require substantial work to
* compute some of the fields and/or update the index.
*/
public class ChangeIndexer {
private static final Logger log =
LoggerFactory.getLogger(ChangeIndexer.class);
public interface Factory {
ChangeIndexer create(ChangeIndex index);
ChangeIndexer create(IndexCollection indexes);
}
private static final Function<Exception, IOException> MAPPER =
new Function<Exception, IOException>() {
@Override
public IOException apply(Exception in) {
if (in instanceof IOException) {
return (IOException) in;
} else if (in instanceof ExecutionException
&& in.getCause() instanceof IOException) {
return (IOException) in.getCause();
} else {
return new IOException(in);
}
}
};
private final IndexCollection indexes;
private final ChangeIndex index;
private final SchemaFactory<ReviewDb> schemaFactory;
private final ChangeData.Factory changeDataFactory;
private final ThreadLocalRequestContext context;
private final ListeningExecutorService executor;
@AssistedInject
ChangeIndexer(@IndexExecutor ListeningExecutorService executor,
SchemaFactory<ReviewDb> schemaFactory,
ChangeData.Factory changeDataFactory,
ThreadLocalRequestContext context,
@Assisted ChangeIndex index) {
this.executor = executor;
this.schemaFactory = schemaFactory;
this.changeDataFactory = changeDataFactory;
this.context = context;
this.index = index;
this.indexes = null;
}
@AssistedInject
ChangeIndexer(@IndexExecutor ListeningExecutorService executor,
SchemaFactory<ReviewDb> schemaFactory,
ChangeData.Factory changeDataFactory,
ThreadLocalRequestContext context,
@Assisted IndexCollection indexes) {
this.executor = executor;
this.schemaFactory = schemaFactory;
this.changeDataFactory = changeDataFactory;
this.context = context;
this.index = null;
this.indexes = indexes;
}
/**
* Start indexing a change.
*
* @param id change to index.
* @return future for the indexing task.
*/
public CheckedFuture<?, IOException> indexAsync(Change.Id id) {
return executor != null
? submit(new Task(id, false))
: Futures.<Object, IOException> immediateCheckedFuture(null);
}
/**
* Synchronously index a change.
*
* @param cd change to index.
*/
public void index(ChangeData cd) throws IOException {
for (ChangeIndex i : getWriteIndexes()) {
i.replace(cd);
}
}
/**
* Synchronously index a change.
*
* @param change change to index.
* @param db review database.
*/
public void index(ReviewDb db, Change change) throws IOException {
index(changeDataFactory.create(db, change));
}
/**
* Start deleting a change.
*
* @param id change to delete.
* @return future for the deleting task.
*/
public CheckedFuture<?, IOException> deleteAsync(Change.Id id) {
return executor != null
? submit(new Task(id, true))
: Futures.<Object, IOException> immediateCheckedFuture(null);
}
/**
* Synchronously delete a change.
*
* @param cd change to delete.
*/
public void delete(ChangeData cd) throws IOException {
for (ChangeIndex i : getWriteIndexes()) {
i.delete(cd);
}
}
/**
* Synchronously delete a change.
*
* @param change change to delete.
* @param db review database.
*/
public void delete(ReviewDb db, Change change) throws IOException {
delete(changeDataFactory.create(db, change));
}
private Collection<ChangeIndex> getWriteIndexes() {
return indexes != null
? indexes.getWriteIndexes()
: Collections.singleton(index);
}
private CheckedFuture<?, IOException> submit(Callable<?> task) {
return Futures.makeChecked(executor.submit(task), MAPPER);
}
private class Task implements Callable<Void> {
private final Change.Id id;
private final boolean delete;
private Task(Change.Id id, boolean delete) {
this.id = id;
this.delete = delete;
}
@Override
public Void call() throws Exception {
try {
final AtomicReference<Provider<ReviewDb>> dbRef =
Atomics.newReference();
RequestContext newCtx = new RequestContext() {
@Override
public Provider<ReviewDb> getReviewDbProvider() {
Provider<ReviewDb> db = dbRef.get();
if (db == null) {
try {
db = Providers.of(schemaFactory.open());
} catch (OrmException e) {
ProvisionException pe =
new ProvisionException("error opening ReviewDb");
pe.initCause(e);
throw pe;
}
dbRef.set(db);
}
return db;
}
@Override
public CurrentUser getCurrentUser() {
throw new OutOfScopeException("No user during ChangeIndexer");
}
};
RequestContext oldCtx = context.setContext(newCtx);
try {
ChangeData cd = changeDataFactory.create(
newCtx.getReviewDbProvider().get(), id);
if (delete) {
for (ChangeIndex i : getWriteIndexes()) {
i.delete(cd);
}
} else {
for (ChangeIndex i : getWriteIndexes()) {
i.replace(cd);
}
}
return null;
} finally {
context.setContext(oldCtx);
Provider<ReviewDb> db = dbRef.get();
if (db != null) {
db.get().close();
}
}
} catch (Exception e) {
log.error(String.format("Failed to index change %d", id.get()), e);
throw e;
}
}
@Override
public String toString() {
return "index-change-" + id.get();
}
}
}