org.flywaydb.database.mysql.MySQLConnection Maven / Gradle / Ivy
/*-
* ========================LICENSE_START=================================
* flyway-mysql
* ========================================================================
* Copyright (C) 2010 - 2024 Red Gate Software Ltd
* ========================================================================
* 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.
* =========================LICENSE_END==================================
*/
package org.flywaydb.database.mysql;
import lombok.CustomLog;
import lombok.Getter;
import org.flywaydb.core.internal.database.base.Connection;
import org.flywaydb.core.internal.database.base.Schema;
import org.flywaydb.core.internal.database.base.Table;
import org.flywaydb.core.internal.exception.FlywaySqlException;
import org.flywaydb.core.internal.util.StringUtils;
import java.sql.SQLException;
import java.util.List;
import java.util.UUID;
import java.util.concurrent.Callable;
@CustomLog
public class MySQLConnection extends Connection {
private static final String USER_VARIABLES_TABLE_MARIADB = "information_schema.user_variables";
private static final String USER_VARIABLES_TABLE_MYSQL = "performance_schema.user_variables_by_thread";
private static final String FOREIGN_KEY_CHECKS = "foreign_key_checks";
private static final String SQL_SAFE_UPDATES = "sql_safe_updates";
private final String userVariablesQuery;
private final boolean canResetUserVariables;
private final int originalForeignKeyChecks;
private final int originalSqlSafeUpdates;
@Getter
private final boolean awsRds;
public MySQLConnection(MySQLDatabase database, java.sql.Connection connection) {
super(database, connection);
userVariablesQuery = "SELECT variable_name FROM "
+ (database.isMariaDB() ? USER_VARIABLES_TABLE_MARIADB : USER_VARIABLES_TABLE_MYSQL)
+ " WHERE variable_value IS NOT NULL";
canResetUserVariables = hasUserVariableResetCapability();
originalForeignKeyChecks = getIntVariableValue(FOREIGN_KEY_CHECKS);
originalSqlSafeUpdates = getIntVariableValue(SQL_SAFE_UPDATES);
awsRds = rdsAdminExists();
}
private int getIntVariableValue(String varName) {
try {
return jdbcTemplate.queryForInt("SELECT @@" + varName);
} catch (SQLException e) {
throw new FlywaySqlException("Unable to determine value for '" + varName + "' variable", e);
}
}
// #2215: ensure the database is recent enough and the current user has the necessary SELECT grant
private boolean hasUserVariableResetCapability() {
if (database.isMariaDB() && !database.getVersion().isAtLeast("10.2")) {
LOG.debug("Disabled user variable reset as it is only available from MariaDB 10.2 onwards");
return false;
}
if (!database.isMariaDB() && !database.getVersion().isAtLeast("5.7")) {
LOG.debug("Disabled user variable reset as it is only available from MySQL 5.7 onwards");
return false;
}
try {
jdbcTemplate.queryForStringList(userVariablesQuery);
return true;
} catch (SQLException e) {
LOG.debug("Disabled user variable reset as "
+ (database.isMariaDB() ? USER_VARIABLES_TABLE_MARIADB : USER_VARIABLES_TABLE_MYSQL)
+ " cannot be queried (SQL State: " + e.getSQLState() + ", Error Code: " + e.getErrorCode() + ")");
return false;
}
}
@Override
protected void doRestoreOriginalState() throws SQLException {
resetUserVariables();
jdbcTemplate.execute("SET " + FOREIGN_KEY_CHECKS + "=?, " + SQL_SAFE_UPDATES + "=?",
originalForeignKeyChecks, originalSqlSafeUpdates);
}
// #2197: prevent user-defined variables from leaking beyond the scope of a migration
private void resetUserVariables() throws SQLException {
if (canResetUserVariables) {
List userVariables = jdbcTemplate.queryForStringList(userVariablesQuery);
if (!userVariables.isEmpty()) {
boolean first = true;
StringBuilder setStatement = new StringBuilder("SET ");
for (String userVariable : userVariables) {
if (first) {
first = false;
} else {
setStatement.append(",");
}
setStatement.append("@").append(userVariable).append("=NULL");
}
jdbcTemplate.executeStatement(setStatement.toString());
}
}
}
@Override
protected String getCurrentSchemaNameOrSearchPath() throws SQLException {
return jdbcTemplate.queryForString("SELECT DATABASE()");
}
@Override
public void doChangeCurrentSchemaOrSearchPathTo(String schema) throws SQLException {
if (StringUtils.hasLength(schema)) {
jdbcTemplate.getConnection().setCatalog(schema);
} else {
try {
// Weird hack to switch back to no database selected...
String newDb = database.quote(UUID.randomUUID().toString());
jdbcTemplate.execute("CREATE SCHEMA " + newDb);
jdbcTemplate.execute("USE " + newDb);
jdbcTemplate.execute("DROP SCHEMA " + newDb);
} catch (Exception e) {
LOG.warn("Unable to restore connection to having no default schema: " + e.getMessage());
}
}
}
@Override
protected Schema doGetCurrentSchema() throws SQLException {
String schemaName = getCurrentSchemaNameOrSearchPath();
// #2206: MySQL and MariaDB can have URLs where no current schema is set, so we must handle this case explicitly.
return schemaName == null ? null : getSchema(schemaName);
}
@Override
public Schema getSchema(String name) {
return new MySQLSchema(jdbcTemplate, database, name);
}
@Override
public T lock(Table table, Callable callable) {
if (canUseNamedLockTemplate()) {
return new MySQLNamedLockTemplate(jdbcTemplate, table.toString().hashCode()).execute(callable);
}
return super.lock(table, callable);
}
protected boolean canUseNamedLockTemplate() {
return !database.isPxcStrict() && !database.isWsrepOn();
}
private boolean rdsAdminExists() {
try {
return StringUtils.hasText(jdbcTemplate.queryForString("SHOW DATABASES LIKE 'RDSAdmin';"));
} catch (Exception e) {
return false;
}
}
}