Download file from dropbox with http4s

JsonHeaderDropbox.scala

import cats.effect.IO
import cats.effect.IOApp
import io.circe.Printer
import io.circe.literal._
import org.http4s.AuthScheme
import org.http4s.Credentials
import org.http4s.Header
import org.http4s.Request
import org.http4s.client.blaze.BlazeClientBuilder
import org.http4s.client.dsl.io._
import org.http4s.dsl.io._
import org.http4s.headers.Authorization
import org.http4s.implicits._
import org.typelevel.ci.CIString

//requires:
//circe-literal 0.14.0-M5
//http4s 1.0.0-M21: blaze-client, dsl, circe

object JsonHeaderDropbox extends IOApp.Simple {

  def downloadFile(filePath: String): Request[IO] =
    POST(uri"https://content.dropboxapi.com/2/files/download")
      .putHeaders(
        Header.Raw(
          name = CIString("Dropbox-API-Arg"),
          // the important part - if you have non-ascii chars in your paths (e.g. you're a normal Polish person),
          // you need to escape them, thankfully circe makes it relatively easy
          value = json"""{"path": $filePath }""".printWith(Printer.noSpaces.copy(escapeNonAscii = true)),
        ),
        Authorization(
          Credentials.Token(
            AuthScheme.Bearer,
            //use ciris instead of reading env variables like this please
            System.getenv("DROPBOX_TOKEN"),
          )
        ),
      )

  def run: IO[Unit] =
    BlazeClientBuilder[IO](runtime.compute)
      .stream
      .flatMap(_.stream(downloadFile("/foo.txt")))
      .flatMap(_.bodyText)
      .debug()
      .compile
      .drain

}