[Kotlin Server] Update Ktor to latest version; move config to kts

[e5l]

• Update the Ktor version in the Kotlin Server template to 2.3.12
• Migrate Ktor gradle configuration to Kotlin Script

technical committee: @stefankoppier

PR checklist

• Read the contribution guidelines.
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  (For Windows users, please run the script in Git BASH)
  Commit all changed files.
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[wing328]

thanks for the PR

cc
@dr4ke616 (2018/08) @karismann (2019/03) @Zomzog (2019/04) @andrewemery (2019/10) @4brunu (2019/11) @yutaka0m (2020/03) @stefankoppier (2022/06)

[wing328]

shall we keep modules/openapi-generator/src/main/resources/kotlin-server/libraries/ktor/build.gradle.mustache as some users may still prefer build.gradle (e.g. they've customized it with additional dependencies only available in their environment) ?

[e5l]

Hey @wing328, thank you for the notice.

According to our stats, less than 0.5% of users use the Groovy script, so we're considering it a legacy and not recommending it for new projects. (We can still add it if necessary.)

By the way, in Ktor support, we received feedback about the generator's confusing naming: while it's named Kotlin, it generates a Ktor server. At the same time, people are struggling to find the Ktor generator in the list. Could you tell me if we can rename it with the deprecation cycle?

[wing328]

https://github.com/OpenAPITools/openapi-generator/actions/runs/11111807665/job/31270994762?pr=19727

can you please take a look when you've time?

[e5l]

Hey @wing328, thanks for the check.
It looks like the Gradle version was outdated.

Bumped to the latest. Could you please check?

[wing328]

@e5l please review the errors when you've time

maybe update gradle to 7.x instead which is still supported (not yet EOL)

[e5l]

Let me try to fix the errors first! It would be nice if we manage to have the latest one :)

[wing328]

It would be nice if we manage to have the latest one :)

not against using the latest version

but we usually test with old versions (not yet EOL) as well to ensure it still works with the auto-generated code

[e5l]

Sure, let me try to stick with the latest 7.* minor so

[e5l]

Force pushed an update to Gradle 7.3. Could you check?

[e5l]

Some samples are using 6.* API, let me update them

[e5l]

Fixed, please check it out

[e5l]

Bump to fix: gradle/gradle#24390

[wing328]

what about filing a separate PR just to update Ktor to latest version and we can merge that one first?

[e5l]

Sure, done!

[wing328]

https://app.circleci.com/pipelines/gh/OpenAPITools/openapi-generator/31893

that can be ignored

if no one has further feedback, i'll merge it tomorrow (Fri)

thanks again for the PR

[e5l]

No problem! Feel free to add me to the Kotlin reviewers if you need volunteers :)

[wing328]

No problem! Feel free to add me to the Kotlin reviewers if you need volunteers :)

Sure, will do. Thanks for joining us 👍

[wing328]

According to our stats, less than 0.5% of users use the Groovy script, so we're considering it a legacy and not recommending it for new projects. (We can still add it if necessary.)

I'm totally ok to decommission it but my guess is that there will be users who still prefer it.

If that occurs, we can add it back.

[wing328]

By the way, in Ktor support, we received feedback about the generator's confusing naming: while it's named Kotlin, it generates a Ktor server. At the same time, people are struggling to find the Ktor generator in the list. Could you tell me if we can rename it with the deprecation cycle?

it's named kotlin-server:

openapi-generator/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/KotlinServerCodegen.java

Line 163 in 7f899df

return "kotlin-server";