Hi folks, the Kotlin Main Kts supports Kotlinx.ser...

# scripting

[SrSouza]

Hi folks, the Kotlin Main Kts supports Kotlinx.serialization ? if so, there is any example of using it?

[mbonnin]

I don't think there is since it requires a plugin. I'm using moshi instead.

[mbonnin]

Maybe you can make kotlinx-serialization work using only the runtime. I guess there's a Json parser there

[mbonnin]

I got curious so made a small test, looks like it is working:

@file:DependsOn("org.jetbrains.kotlinx:kotlinx-serialization-json-jvm:1.0.1")

import kotlinx.serialization.json.*


val jsonObject = JsonObject(
    mapOf(
        "int" to JsonPrimitive(0),
        "double" to JsonPrimitive(0.5),
        "string" to JsonPrimitive("String"),
        "bool" to JsonPrimitive(true),
        "list" to JsonArray(
            listOf(
                JsonPrimitive(0),
                JsonPrimitive(1),
                JsonPrimitive(2),
                JsonPrimitive(3)
            )
        ),
        "object" to JsonObject(
            mapOf("key" to JsonPrimitive("value")
            )
        )
    )
)


println(Json.parseToJsonElement(jsonObject.toString()))

[ilya.chernikov]

Since 1.4.20 you can use plugins with main-kts, in particular with kotlinx.serialization, see, e.g., the test here - https://github.com/JetBrains/kotlin/blob/master/libraries/tools/kotlin-main-kts-test/test/org/jetbrains/kotlin/mainKts/test/mainKtsIT.kt#L94

[mbonnin]

Nice! Can the plugin be added from the *.main.kts file itself ? Or does it always need the -Xplugin parameter?

[mbonnin]

(and where can I find the plugin path if -Xplugin is mandatory?)

[ilya.chernikov]

No, unfortunately you need to configure plugin via the -Xplugin parameter to the kotlinc. (or you can write a custom host/runner that includes the plugin by default.)
The plugin is installed along with kotlin CLI compiler, to the $KOTLIN_HOME/lib/.

[mbonnin]

So... I just tried and it seems to work without specifying -Xplugin ? 🤔

martin@MacBook:~/dev/kotlinc$ kotlinc -script serialization.main.kts  
{"firstName":"James","lastName":"Bond"}
User(firstName=James, lastName=Bond)

[mbonnin]

Which is a good thing I guess? Just wondering if I'm missing something there

[mbonnin]

Now the only thing missing is IDE support 😇

[ilya.chernikov]

I don't know, why it works. Maybe it was enabled by default at some point, but I cannot find any traces of it so far. I'll check with the serialization authors a bit later.
IDE support for advanced scripting features is lagging behind, unfortunately. Cannot cover everything.

[mbonnin]

Interestingly, this was working because I was experimenting with shebang magic and I had #!$KOTLIN_HOME/bin/kotlinc -Xplugin=$KOTLIN_HOME at the start of my file...

[mbonnin]

Note that despite having the shebang, I was still calling kotlinc -script serialization.main.kts manually

[mbonnin]

So that would hint at kotlinc somehow reading the shebang line?

[Piotr Krzemiński]

I'm also missing a convenient way to use some of the Gradle plugins, see: https://youtrack.jetbrains.com/issue/KT-47384