com.logsniffer.app.DataSourceAppConfig.java Source code

Introduction

Here is the source code for com.logsniffer.app.DataSourceAppConfig.java

Source

/*******************************************************************************
 * logsniffer, open source tool for viewing, monitoring and analysing log data.
 * Copyright (c) 2015 Scaleborn UG, www.scaleborn.com
 *
 * logsniffer is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * logsniffer 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *******************************************************************************/
package com.logsniffer.app;

import java.sql.Connection;
import java.sql.SQLException;

import javax.sql.DataSource;

import org.flywaydb.core.Flyway;
import org.flywaydb.core.api.MigrationVersion;
import org.h2.jdbcx.JdbcConnectionPool;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.beans.factory.config.ConfigurableBeanFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Scope;
import org.springframework.core.io.ClassPathResource;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.datasource.init.ResourceDatabasePopulator;

/**
 * Configured the live datasource.
 * 
 * @author mbok
 * 
 */
@Configuration
public class DataSourceAppConfig {
    private static final String DB_SETUP_VERSION = "0.5.5";

    private final Logger logger = LoggerFactory.getLogger(getClass());

    @Value(value = "${logsniffer.h2.user}")
    private String user;

    @Value(value = "${logsniffer.h2.password}")
    private String password;

    @Value(value = "${logsniffer.h2.url}")
    private String url;

    @Value(value = "${logsniffer.h2.maxPoolConnections:5}")
    private final int maxPoolConnections = 5;

    private boolean newSchema = false;

    /**
     * Used to indicate if DB is initialized the first time. It helps to drive
     * further DB initializations.
     * 
     * @author mbok
     * 
     */
    public static interface DBInitIndicator {
        /**
         * Returns true if DB was initialized.
         * 
         */
        boolean isNewSchema();
    }

    /**
     * @return H2 pooled data source
     * @throws SQLException
     */
    @Bean(destroyMethod = "dispose")
    public DataSource dataSource() throws SQLException {
        final JdbcConnectionPool pool = JdbcConnectionPool.create(url, user, password);
        pool.setMaxConnections(maxPoolConnections);
        Connection con = null;
        con = pool.getConnection();

        final Flyway flyway = new Flyway();
        flyway.setLocations("classpath:sql/migration");
        flyway.setDataSource(pool);
        flyway.setSqlMigrationPrefix("VOS-");
        flyway.setIgnoreFailedFutureMigration(true);

        final JdbcTemplate tpl = new JdbcTemplate(pool);
        if (tpl.queryForObject("select count(*) from information_schema.tables where table_name = 'LOG_SOURCES'",
                int.class) == 0) {
            logger.info("H2 database not found, creating new schema and populate with default data");
            flyway.setBaselineVersion(MigrationVersion.fromVersion(DB_SETUP_VERSION));
            flyway.setBaselineOnMigrate(true);
            try {
                final ResourceDatabasePopulator dbPopulator = new ResourceDatabasePopulator();
                dbPopulator.addScript(new ClassPathResource("/sql/quartz/tables_h2.sql"));
                dbPopulator.addScript(new ClassPathResource("/sql/model/schema_h2.sql"));
                dbPopulator.populate(con);
                newSchema = true;
                logger.info("Established H2 connection pool with new database");
            } finally {
                if (con != null) {
                    con.close();
                }
            }
        } else {
            logger.info("Established H2 connection pool with existing database");
            if (tpl.queryForObject(
                    "select count(*) from information_schema.tables where table_name = 'schema_version'",
                    int.class) == 0) {
                logger.info("Flyway's DB migration not setup in this version, set baseline version to 0.5.0");
                flyway.setBaselineVersion(MigrationVersion.fromVersion("0.5.0"));
                flyway.setBaselineOnMigrate(true);
            }
        }

        logger.debug("Migrating database, base version is: {}", flyway.getBaselineVersion());
        flyway.migrate();
        logger.debug("Database migrated from base version: {}", flyway.getBaselineVersion());

        return pool;
    }

    @Bean
    @Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
    @Autowired
    public JdbcTemplate jdbcTemplate(final DataSource dataSource) {
        return new JdbcTemplate(dataSource);
    }

    @Bean
    public DBInitIndicator dbInitPopulate() {
        return new DBInitIndicator() {

            @Override
            public boolean isNewSchema() {
                return newSchema;
            }
        };
    }
}