gerrit-lucene/src/main/java/com/google/gerrit/lucene/IndexVersionCheck.java

// 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.git;

package com.google.gerrit.lucene;

import static com.google.gerrit.lucene.LuceneChangeIndex.LUCENE_VERSION;

import static org.apache.lucene.util.Version.LUCENE_CURRENT;

import com.google.common.collect.ImmutableMap;
import com.google.gerrit.extensions.events.LifecycleListener;
import com.google.gerrit.server.config.SitePaths;
import com.google.gerrit.server.index.ChangeField;
import com.google.inject.Inject;
import com.google.inject.ProvisionException;

import org.apache.lucene.util.Version;
import org.eclipse.jgit.errors.ConfigInvalidException;
import org.eclipse.jgit.storage.file.FileBasedConfig;
import org.eclipse.jgit.util.FS;

import java.io.File;
import java.io.IOException;
import java.util.Map;

public class IndexVersionCheck implements LifecycleListener {
  public static final Map<String, Integer> SCHEMA_VERSIONS = ImmutableMap.of(
      LuceneChangeIndex.CHANGES_OPEN, ChangeField.SCHEMA_VERSION,
      LuceneChangeIndex.CHANGES_CLOSED, ChangeField.SCHEMA_VERSION);

  public static File gerritIndexConfig(SitePaths sitePaths) {
    return new File(sitePaths.index_dir, "gerrit_index.config");
  }

  private final SitePaths sitePaths;

  @Inject
  IndexVersionCheck(SitePaths sitePaths) {
    this.sitePaths = sitePaths;
  }

  @Override
  public void start() {
    File file = gerritIndexConfig(sitePaths);
    try {
      FileBasedConfig cfg = new FileBasedConfig(file, FS.detect());
      cfg.load();
      for (Map.Entry<String, Integer> e : SCHEMA_VERSIONS.entrySet()) {
        int schemaVersion = cfg.getInt("index", e.getKey(), "schemaVersion", 0);
        if (schemaVersion != e.getValue()) {
          throw new ProvisionException(String.format(
              "wrong index schema version for \"%s\": expected %d, found %d%s",
              e.getKey(), e.getValue(), schemaVersion, upgrade()));
        }
      }
      @SuppressWarnings("deprecation")
      Version luceneVersion =
          cfg.getEnum("lucene", null, "version", LUCENE_CURRENT);
      if (luceneVersion != LUCENE_VERSION) {
        throw new ProvisionException(String.format(
            "wrong Lucene version: expected %d, found %d%s",
            luceneVersion, LUCENE_VERSION, upgrade()));

      }
    } catch (IOException e) {
      throw new ProvisionException("unable to read " + file);
    } catch (ConfigInvalidException e) {
      throw new ProvisionException("invalid config file " + file);
    }
  }

  @Override
  public void stop() {
    // Do nothing.
  }

  private final String upgrade() {
    return "\nRun reindex to rebuild the index:\n"
      + "$ java -jar gerrit.war reindex -d "
      + sitePaths.site_path.getAbsolutePath();
  }
}