Wondering if the new `KotlinInstantColumnType` ca...

# exposed

[dave08]

Wondering if the new KotlinInstantColumnType can handle an int field that stores a unix timestamp?

[tapac]

Is it fails on getTimestamp call?
What database do you use?

[dave08]

I didn't actually try it, I just looked through the source code, and saw that you use Instant.parse, and for anything not a String or sql Timestamp, you convert to a string and use that parse function, so it really shouldn't work for integers that represent epochSeconds @tapac

[dave08]

And besides the point, the underlying sqltype isn't integer in your implementation, so when creating the schema, it would create the wrong field type...

[dave08]

I use mysql in that particular case... but this should be an issue for all implementations... I just don't know how often people save epochSeconds as ints...

[tapac]

It depends on how you use it.
If you use mapping for existing table with long/int column containing instantant value than driver can return in as a Timestamp on ResultSet.getTimestamp call.
If you create table from scratch with Exposed than it will create a db-specific type and everything should also work

[tapac]

Also, storing instant as a second representation is not a good idea as instant have millis/nanos parts

[dave08]

You have:

override fun valueFromDB(value: Any): Instant = when (value) {
        is java.sql.Timestamp -> value.toInstant().toKotlinInstant()
        is String -> Instant.parse(value)
        else -> valueFromDB(value.toString())
    }

in my case it should reach the else... converting the int to a string, and ending up in Instant.parse... if this would be to work, there should have been an extra is Int -> Instant.fromEpochSeconds(value, 0)... but I guess this isn't a common use-case... but it would still have been nice to have some kind of transform(fromDb: (FieldType) -> RequiredType, toDb: (RequiredType) -> FieldType)... for this and other use-cases...

[dave08]

in the field definition on the Table...

[dave08]

like val startTimestap: Instant = integer("start_at").transform({ Instant.fromEpochSeconds(it, 0) }, { it.epochSeconds })