How to properly create and connect to database with Kotlin Exposed? - kotlin

Question

I did check the similar question here, but it didn't work as expected for me, I still need to reconnect to the created database and I'm not sure how or even if I can avoid that.
Here is my code:
hikari.properties:
jdbcUrl=jdbc:mariadb://localhost:3306/
driverClassName=org.mariadb.jdbc.Driver
username=root
dataSource.databaseName=DBNAME //this doesn't seem to do much, I'm getting the same behavior with or without it
fun initDB() {
val config = HikariConfig("/hikari.properties")
val ds = HikariDataSource(config)
transaction(connect(ds)) {
SchemaUtils.createDatabase("DBNAME")
}
config.jdbcUrl = "jdbc:mariadb://localhost:3306/DBNAME"
//ds.jdbcUrl = "jdbc:mariadb://localhost:3306/DBNAME" //THIS WILL NOT WORK
val ds2 = HikariDataSource(config)
transaction(connect(ds2)) {
SchemaUtils.create( Tables... )
}
}
The reason I make a new datasource, is because otherwise I'll get this error:
java.lang.IllegalStateException: The configuration of the pool is sealed once started. Use HikariConfigMXBean for runtime changes. HikariConfigMXBean doesn't seem allow jdbcUrl changes.
There must be a more elegant way to do this, right?

Answer 1

It is not a good practice. Creating and filling db it is two separate processes. DB creates once by the DBA, then you just connect and use it. Your approach has huge security violation. User from the datasource must have create db privilege.
But if you want proceed with your current approach, first you should create a db without using datasource, then create datasource and connect to the db. Something like this
import com.zaxxer.hikari.HikariConfig
import com.zaxxer.hikari.HikariDataSource
import org.jetbrains.exposed.sql.Database
import org.jetbrains.exposed.sql.SchemaUtils
import org.jetbrains.exposed.sql.Table
import org.jetbrains.exposed.sql.transactions.transaction
fun main(args: Array<String>) {
//LOAD proerties
val config = HikariConfig("/hikari.properties")
//Hikari properties content
// jdbcUrl=jdbc:mysql://localhost:3306/hikari
// driverClassName=com.mysql.cj.jdbc.Driver
// username=root
// password=<pwd here>
//Here replace dbname from jdbc url to empty
transaction(Database.connect(url = config.jdbcUrl.replace("hikari", ""),
driver = config.driverClassName,
user = config.username,
password = config.password)) {
SchemaUtils.createDatabase("hikari")
}
val ds = HikariDataSource(config)
transaction(Database.connect(ds)) {
SchemaUtils.create(Users)
}
}
object Users : Table() {
val id = varchar("id", 10) // Column<String>
val name = varchar("name", length = 50) // Column<String>
override val primaryKey = PrimaryKey(id, name = "PK_User_ID")
}