io.druid.metadata.storage.mysql.MySQLConnector.java Source code

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Here is the source code for io.druid.metadata.storage.mysql.MySQLConnector.java

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/*
 * Druid - a distributed column store.
 * Copyright 2012 - 2015 Metamarkets Group Inc.
 *
 * 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 io.druid.metadata.storage.mysql;

import com.google.common.base.Supplier;
import com.google.common.collect.ImmutableList;
import com.google.inject.Inject;
import com.metamx.common.ISE;
import com.metamx.common.logger.Logger;
import com.mysql.jdbc.exceptions.MySQLTransientException;
import io.druid.metadata.MetadataStorageConnectorConfig;
import io.druid.metadata.MetadataStorageTablesConfig;
import io.druid.metadata.SQLMetadataConnector;
import org.apache.commons.dbcp2.BasicDataSource;
import org.skife.jdbi.v2.DBI;
import org.skife.jdbi.v2.Handle;
import org.skife.jdbi.v2.tweak.HandleCallback;

import java.sql.SQLException;

public class MySQLConnector extends SQLMetadataConnector {
    private static final Logger log = new Logger(MySQLConnector.class);
    private static final String PAYLOAD_TYPE = "LONGBLOB";
    private static final String SERIAL_TYPE = "BIGINT(20) AUTO_INCREMENT";

    private final DBI dbi;

    @Inject
    public MySQLConnector(Supplier<MetadataStorageConnectorConfig> config,
            Supplier<MetadataStorageTablesConfig> dbTables) {
        super(config, dbTables);

        final BasicDataSource datasource = getDatasource();
        // MySQL driver is classloader isolated as part of the extension
        // so we need to help JDBC find the driver
        datasource.setDriverClassLoader(getClass().getClassLoader());
        datasource.setDriverClassName("com.mysql.jdbc.Driver");

        // use double-quotes for quoting columns, so we can write SQL that works with most databases
        datasource.setConnectionInitSqls(ImmutableList.of("SET sql_mode='ANSI_QUOTES'"));

        this.dbi = new DBI(datasource);

        log.info("Configured MySQL as metadata storage");
    }

    @Override
    protected String getPayloadType() {
        return PAYLOAD_TYPE;
    }

    @Override
    protected String getSerialType() {
        return SERIAL_TYPE;
    }

    @Override
    public boolean tableExists(Handle handle, String tableName) {
        // ensure database defaults to utf8, otherwise bail
        boolean isUtf8 = handle
                .createQuery("SHOW VARIABLES where variable_name = 'character_set_database' and value = 'utf8'")
                .list().size() == 1;

        if (!isUtf8) {
            throw new ISE("Database default character set is not UTF-8." + System.lineSeparator()
                    + "  Druid requires its MySQL database to be created using UTF-8 as default character set."
                    + " If you are upgrading from Druid 0.6.x, please make all tables have been converted to utf8 and change the database default."
                    + " For more information on how to convert and set the default, please refer to section on updating from 0.6.x in the Druid 0.7.1 release notes.");
        }

        return !handle.createQuery("SHOW tables LIKE :tableName").bind("tableName", tableName).list().isEmpty();
    }

    @Override
    protected boolean connectorIsTransientException(Throwable e) {
        return e instanceof MySQLTransientException || (e instanceof SQLException
                && ((SQLException) e).getErrorCode() == 1317 /* ER_QUERY_INTERRUPTED */);
    }

    @Override
    public Void insertOrUpdate(final String tableName, final String keyColumn, final String valueColumn,
            final String key, final byte[] value) throws Exception {
        return getDBI().withHandle(new HandleCallback<Void>() {
            @Override
            public Void withHandle(Handle handle) throws Exception {
                handle.createStatement(String.format(
                        "INSERT INTO %1$s (%2$s, %3$s) VALUES (:key, :value) ON DUPLICATE KEY UPDATE %3$s = :value",
                        tableName, keyColumn, valueColumn)).bind("key", key).bind("value", value).execute();
                return null;
            }
        });
    }

    @Override
    public DBI getDBI() {
        return dbi;
    }
}