JSON support using Jackson

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The Jackson feature allows you to handle JSON content in your application easily using the jackson library.

This feature is a ContentNegotiation converter.

This feature is defined in the class io.ktor.jackson.JacksonConverter in the artifact io.ktor:ktor-jackson:$ktor_version.

dependencies {
    compile "io.ktor:ktor-jackson:$ktor_version"
}

dependencies {
    compile("io.ktor:ktor-jackson:$ktor_version")
}

<project>
    ...
    <dependencies>
        <dependency>
            <groupId>io.ktor</groupId>
            <artifactId>ktor-jackson</artifactId>
            <version>${ktor.version}</version>
            <scope>compile</scope>
        </dependency>
    </dependencies>
</project>

Basic usage

To install the feature by registering a JSON content convertor using Jackson:

install(ContentNegotiation) {
    jackson {
        // Configure Jackson's ObjectMapper here
    }
}

The jackson block is a convenient method for:

register(ContentType.Application.Json, JacksonConverter(ObjectMapper().apply {
    // ...
}.create()))

Configuration

Inside the jackson block, you have access to the ObjectMapper used to install the ContentNegotiation. To give you an idea of what is available:

install(ContentNegotiation) {
    jackson {
        enable(SerializationFeature.INDENT_OUTPUT)
        enable(...)
        dateFormat = DateFormat.getDateInstance()
        disableDefaultTyping()
        convertValue(..., ...)
        ...
    }
}