KomapperCreatedAt and truncate time

[Distractic]

Hello !

I have this class :

public data class Guild(
    @KomapperId
    @KomapperAutoIncrement
    val id: Int,
    val name: String,
    val owner: UUID,
    @KomapperCreatedAt
    val createdAt: Instant,
)

To create my database data, I'm doing :

suspend fun createGuild(name: String, owner: UUID): Guild {
        val guild = Guild(0, name, owner, Instant.EPOCH)
        val query = QueryDsl.insert(_Guild.guild).single(guild)
        return database.runQuery(query)
    }

However, in my test, the guild returned from the runQuery is not the same than the instance in database due to createdAt value.

My test :

@Nested
    inner class CreateGuild {

        @Test
        fun `when owner is already in a guild`() = runTest {
            val guild = service.createGuild("test", UUID.randomUUID())
            val guild2 = service.createGuild("test2", guild.owner)
            assertNotEquals(guild.id, guild2.id)

            val guilds = getAll()
            assertEquals(2, guilds.size)
            assertEquals(guild, guilds[0])
            assertEquals(guild2, guilds[1])
        }

    }

    private suspend fun getAll(): List<Guild> {
        return DatabaseUtils.getAll(database, _Guild.guild)
    }

However, I have this error :

Expected :Guild(id=1, name=test, owner=5f03299b-7f50-404a-b91a-94ea5651795d, createdAt=2023-03-23T16:41:18.038747100Z)
Actual   :Guild(id=1, name=test, owner=5f03299b-7f50-404a-b91a-94ea5651795d, createdAt=2023-03-23T16:41:18.038747Z)

If I try to truncate the createdAt, like

val guild = service.createGuild("test", UUID.randomUUID()).let {
                it.copy(createdAt = it.createdAt.truncatedTo(java.time.temporal.ChronoUnit.MICROS))
}
val guild2 = service.createGuild("test2", guild.owner).let {
                it.copy(createdAt = it.createdAt.truncatedTo(java.time.temporal.ChronoUnit.MICROS))
}

The error is :

Expected :Guild(id=1, name=test, owner=1e348956-159c-4813-a6ba-371d8a6d50a1, createdAt=2023-03-23T16:48:42.977570Z)
Actual   :Guild(id=1, name=test, owner=1e348956-159c-4813-a6ba-371d8a6d50a1, createdAt=2023-03-23T16:48:42.977571Z)

So I have two questions :

• Is it possible to set the time precision (truncate to second for example)
• How can I get the same time between my database instance and my instance returned by the runQuery

[nakamura-to]

PostgreSQL drivers seem to round up nanoseconds.

You can use ClockProvider.

Create the following class:

import org.komapper.core.ClockProvider
import java.time.Clock
import java.time.Instant
import java.time.ZoneId
import java.time.temporal.ChronoUnit

class MicroClockProvider(private val zoneId: ZoneId = ZoneId.systemDefault()) : ClockProvider {
    override fun now(): Clock {
        val instant = Instant.now().truncatedTo(ChronoUnit.MICROS)
        return Clock.fixed(instant, zoneId)
    }
}

Set an instance of the above class to JdbcDatabase or R2dbcDatabase:

val database = R2dbcDatabase(clockProvider = MicroClockProvider())

See also https://www.komapper.org/docs/reference/database-config/#clockprovider .