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jsonkotlinjavalinktorm

How to configure the default Jackson JSON Mapper on Javalin

So far, i found how to replace Javalin json mapper:

https://javalin.io/documentation#configuring-the-json-mapper

But i don't want to replace it, just want to add a few jackson modules, like this one:

https://www.ktorm.org/api-docs/org.ktorm.jackson/-ktorm-module/index.html

Without this, Javalin fails to serialize ktorm entities, sample code here

Solution

  • Solved!

    In JavalinConfig you can set an implementation of JsonMapper

    The default implementation accepts an ObjectMapper as parameter, so i can do this:

    // custom config to make ktor and jackson behave
val mapper = ObjectMapper()
mapper.registerModule(JavaTimeModule())
mapper.registerModule(KotlinModule.Builder().build())
mapper.registerModule(KtormModule())

// spin up app
val app = Javalin.create {
    it.jsonMapper(JavalinJackson(mapper))
}.start(3000)

    And then Javalin and Ktorm works perfectly together.

    UPDATE:

    Now Javalin will detect KtormModule for you!