Kotlin

import java.net.URI
import java.net.http.HttpClient
import java.net.http.HttpRequest
import java.net.http.HttpResponse

fun main() {
    val body = """
        {
          "subject": "Hello from Mailtarget",
          "from": { "email": "you@your-verified-domain.com", "name": "Your Name" },
          "to": [{ "email": "recipient@example.com" }],
          "bodyText": "If you can read this, the integration works."
        }
    """.trimIndent()

    val request = HttpRequest.newBuilder()
        .uri(URI.create("https://transmission.mailtarget.co/v1/layang/transmissions"))
        .header("Authorization", "Bearer " + System.getenv("MAILTARGET_API_KEY"))
        .header("Content-Type", "application/json")
        .POST(HttpRequest.BodyPublishers.ofString(body))
        .build()

    val response = HttpClient.newHttpClient()
        .send(request, HttpResponse.BodyHandlers.ofString())

    println(response.statusCode())
    println(response.body())
}