Jackson

ContentNegotiation provides the built-in Jackson converter for handing JSON data in your application.

Add Dependencies

Before registering the Jackson converter, you need to include the following artifacts in the build script:

Gradle (Groovy)

Gradle (Kotlin)

Maven

implementation "io.ktor:ktor-jackson:$ktor_version"

Register the Jackson Converter

To register the Jackson converter in your application, call the jackson method:

import io.ktor.jackson.*
install(ContentNegotiation) {
    jackson()
}

Inside the jackson block, you can access the ObjectMapper API, for example:

install(ContentNegotiation) {
    jackson {
        enable(SerializationFeature.INDENT_OUTPUT)
        dateFormat = DateFormat.getDateInstance()
        // ...
    }
}

To learn how to receive and send data, see Receive and Send Data.