Java tutorial
/* * SonarQube * Copyright (C) 2009-2017 SonarSource SA * mailto:info AT sonarsource DOT com * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 3 of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this program; if not, write to the Free Software Foundation, * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ package org.sonar.server.platform.ws; import com.google.common.io.Resources; import org.sonar.api.platform.Server; import org.sonar.api.server.ws.Request; import org.sonar.api.server.ws.Response; import org.sonar.api.server.ws.WebService; import org.sonar.api.utils.log.Logger; import org.sonar.api.utils.log.Loggers; import org.sonar.api.utils.text.JsonWriter; import org.sonar.db.DbClient; import org.sonar.db.DbSession; import org.sonar.db.IsAliveMapper; import org.sonar.server.app.RestartFlagHolder; import org.sonar.server.platform.Platform; import org.sonar.server.platform.db.migration.DatabaseMigrationState; /** * Implementation of the {@code status} action for the System WebService. */ public class StatusAction implements SystemWsAction { private static final Logger LOGGER = Loggers.get(StatusAction.class); private final Server server; private final DatabaseMigrationState migrationState; private final Platform platform; private final DbClient dbClient; private final RestartFlagHolder restartFlagHolder; public StatusAction(Server server, DatabaseMigrationState migrationState, Platform platform, DbClient dbClient, RestartFlagHolder restartFlagHolder) { this.server = server; this.migrationState = migrationState; this.platform = platform; this.dbClient = dbClient; this.restartFlagHolder = restartFlagHolder; } @Override public void define(WebService.NewController controller) { controller.createAction("status").setDescription("Get the server status:" + "<ul>" + "<li>STARTING: SonarQube Web Server is up and serving some Web Services (eg. api/system/status) " + "but initialization is still ongoing</li>" + "<li>UP: SonarQube instance is up and running</li>" + "<li>DOWN: SonarQube instance is up but not running because SQ can not connect to database or " + "migration has failed (refer to WS /api/system/migrate_db for details) or some other reason (check logs).</li>" + "<li>RESTARTING: SonarQube instance is still up but a restart has been requested " + "(refer to WS /api/system/restart for details).</li>" + "<li>DB_MIGRATION_NEEDED: database migration is required. DB migration can be started using WS /api/system/migrate_db.</li>" + "<li>DB_MIGRATION_RUNNING: DB migration is running (refer to WS /api/system/migrate_db for details)</li>" + "</ul>").setSince("5.2") .setResponseExample(Resources.getResource(this.getClass(), "example-status.json")).setHandler(this); } @Override public void handle(Request request, Response response) throws Exception { JsonWriter json = response.newJsonWriter(); writeJson(json); json.close(); } private void writeJson(JsonWriter json) { Status status = computeStatus(); json.beginObject(); json.prop("id", server.getId()); json.prop("version", server.getVersion()); json.prop("status", status.toString()); json.endObject(); } private Status computeStatus() { if (!isConnectedToDB()) { return Status.DOWN; } Platform.Status platformStatus = platform.status(); switch (platformStatus) { case BOOTING: // can not happen since there can not even exist an instance of the current class // unless the Platform's status is UP/SAFEMODE/STARTING return Status.DOWN; case UP: return restartFlagHolder.isRestarting() ? Status.RESTARTING : Status.UP; case STARTING: return computeStatusInStarting(); case SAFEMODE: return computeStatusInSafemode(); default: throw new IllegalArgumentException("Unsupported Platform.Status " + platformStatus); } } private boolean isConnectedToDB() { try (DbSession dbSession = dbClient.openSession(false)) { return dbSession.getMapper(IsAliveMapper.class).isAlive() == IsAliveMapper.IS_ALIVE_RETURNED_VALUE; } catch (RuntimeException e) { LOGGER.error("DB connection is down", e); return false; } } private Status computeStatusInStarting() { DatabaseMigrationState.Status databaseMigrationStatus = migrationState.getStatus(); switch (databaseMigrationStatus) { case NONE: return Status.STARTING; case RUNNING: return Status.DB_MIGRATION_RUNNING; case FAILED: return Status.DOWN; case SUCCEEDED: // DB migration can be finished while we haven't yet finished SQ's initialization return Status.STARTING; default: throw new IllegalArgumentException("Unsupported DatabaseMigration.Status " + databaseMigrationStatus); } } private Status computeStatusInSafemode() { DatabaseMigrationState.Status databaseMigrationStatus = migrationState.getStatus(); switch (databaseMigrationStatus) { case NONE: return Status.DB_MIGRATION_NEEDED; case RUNNING: return Status.DB_MIGRATION_RUNNING; case FAILED: return Status.DOWN; case SUCCEEDED: return Status.STARTING; default: throw new IllegalArgumentException("Unsupported DatabaseMigration.Status " + databaseMigrationStatus); } } private enum Status { UP, DOWN, DB_MIGRATION_NEEDED, DB_MIGRATION_RUNNING, STARTING, RESTARTING } }