I'm having trouble upgrading to kotlin 1.9.0 due to kotlinx-serialization. When I change the plugin ...

# serialization

[Rasmus]

I'm having trouble upgrading to kotlin 1.9.0 due to kotlinx-serialization. When I change the plugin version reference for kotlinx-serialization to 1.9.0 for some reason Gradle attempts to download plugin version 1.8.10 instead. This fails for some reason, but it looks like version 1.8.10 does exist 🤷‍♂️. We are using kotlinx-serialization 1.5.1 btw. My first thought was that there is some kind of cache issue, but I tried clearing everything. Besides, the previous version we used was version 1.8.21 which worked fine.

We're using version catalog to define the plugin: plugin("kotlin-serialization", "org.jetbrains.kotlin.plugin.serialization").version("1.9.0") and alias to bring in the plugin: alias(_libs_._plugins_._kotlin_._serialization_), if it's overridden with .version("1.8.21") the build succeeds, so I don't think it's related to how the plugin is loaded.

This is the error output I get:

Execution failed for task ':core:compileKotlin'.
Could not resolve all files for configuration ':core:kotlinCompilerPluginClasspathMain'.
   > Could not find org.jetbrains.kotlin:kotlin-serialization-compiler-plugin-embeddable:1.8.10.
     Searched in the following locations:
       - <https://repo.maven.apache.org/maven2/org/jetbrains/kotlin/kotlin-serialization-compiler-plugin-embeddable/1.8.10/kotlin-serialization-compiler-plugin-embeddable-1.8.10.pom>
     If the artifact you are trying to retrieve can be found in the repository but without metadata in 'Maven POM' format, you need to adjust the 'metadataSources { ... }' of the repository declaration.
     Required by:
         project :core

Any ideas?

[ephemient]

the plugin version should match the compiler version, not the library version

[ephemient]

are you somehow using KGP 1.8.x still? (for example, is there part of your build that is using kotlin-dsl or embedded-kotlin to build a gradle plugin?)

[Rasmus]

Kotlin version is only specified in my settings.gradle.kts afaik

[Rasmus]

I am loading ``kotlin-dsl`` but without specifying a version

[Rasmus]

Oh i see, that seems to be the problem

[Rasmus]

So kotlin-dsl is supposed to be set through the gradle version, but there doesnt seem to be a gradle version that uses 1.9.0 yet. I was using gradle 8.1.1 which I now upgraded to 8.2. This changes the kotlin-dsl version to use kotlin 1.8.22 which still does not solve the original problem.

[ephemient]

yes. if you are using kotlin-dsl you are locked to Gradle's embedded Kotlin version, and it still is 1.8

[ephemient]

I would recommend using embeddedKotlinVersion in your build scripts instead of the version catalog, for compatibility with kotlin-dsl / embedded-kotlin. for example,

plugins {
    `kotlin-dsl`
   kotlin("plugin.serialization") version embeddedKotlinVersion
}

[Rasmus]

I was just thinking about how to do that instead, thanks! 😂