ktor - is there a way to serialize sub-template Template<FlowContent> to txt/html? - ktor

Question

I am using HTML DSL as the templating engine in my ktor project.
I am trying to send one of the sub-templates Template as a text response (I do not want to send the full HtmlTemplate).
So far I have got below - to make it work I have to wrap my TestTemplate in another div:
fun Route.test() {
get("/test") {
call.respondText(
buildString {
appendHTML().div {
insert(TestTemplate(), TemplatePlaceholder())
}
}
)
}
}
This gives me following response (the inner div is my TestTemplate):
<div>
<div>this is the element I want to get, without the outer element</div>
</div>
What I would like to get is just the TestTemplate:
<div>this is the element I want to get, without the outer element</div>
Is there a way to achieve it in ktor using the HTML DSL?

Answer 1

You can make a class for the template with an HTMLStreamBuilder<StringBuilder> type parameter instead of FlowContent to build a final HTML string without any tags (FlowContent inherits Tag interface).
import io.ktor.application.*
import io.ktor.html.*
import io.ktor.response.*
import io.ktor.routing.*
import io.ktor.server.engine.*
import io.ktor.server.netty.*
import kotlinx.html.*
import kotlinx.html.stream.HTMLStreamBuilder
suspend fun main() {
embeddedServer(Netty, port = 3333) {
routing {
get("/test") {
val builder = StringBuilder()
val html: HTMLStreamBuilder<StringBuilder> = HTMLStreamBuilder(builder, prettyPrint = true, xhtmlCompatible = false)
html.insert(TestTemplate(), TemplatePlaceholder())
call.respondText(html.finalize().toString())
}
}
}.start()
}
class TestTemplate : Template<HTMLStreamBuilder<StringBuilder>> {
val articleTitle = Placeholder<FlowContent>()
val articleText = Placeholder<FlowContent>()
override fun HTMLStreamBuilder<StringBuilder>.apply() {
article {
h2 {
insert(articleTitle)
}
p {
insert(articleText)
}
}
}
}