Publishing Json

A stream-based Json Encoder that can be connected to a Publisher is provided by the extra dependency fs2-rabbit-circe. Implicit encoders for your classes must be on scope. You can use Circe’s codec auto derivation for example:

import cats.effect.IO
import dev.profunktor.fs2rabbit.json.Fs2JsonEncoder
import dev.profunktor.fs2rabbit.model._
import fs2.Stream

case class Address(number: Int, streetName: String)
case class Person(id: Long, name: String, address: Address)

object ioEncoder extends Fs2JsonEncoder

def program(publisher: AmqpMessage[String] => IO[Unit]) = {
  import ioEncoder._

  val message = AmqpMessage(Person(1L, "Sherlock", Address(212, "Baker St")), AmqpProperties.empty)

If you need to modify the output format, you can pass your own io.circe.Printer to the constructor of Fs2JsonEncoder (defaults to Printer.noSpaces).