如何用Circe从Doobie Scala PostgreSQL数据库中读取JSON？

libraryDependencies ++= Seq(
  "io.circe" %% "circe-core" % "x.x.x",
  "io.circe" %% "circe-parser" % "x.x.x",
  "org.tpolecat" %% "doobie-core" % "x.x.x",
  "org.tpolecat" %% "doobie-postgres" % "x.x.x"
)

db {
  driver = "org.postgresql.Driver"
  url = "jdbc:postgresql://localhost:5432/mydatabase"
  user = "myuser"
  password = "mypassword"
}

import io.circe._
import io.circe.generic.semiauto._

case class MyData(id: Int, json: Json)

object MyData {
  implicit val decoder: Decoder[MyData] = deriveDecoder[MyData]
  implicit val encoder: Encoder[MyData] = deriveEncoder[MyData]
}

import cats.effect._
import doobie._
import doobie.implicits._
import io.circe.parser._

val xa = Transactor.fromDriverManager[IO](
  "org.postgresql.Driver",
  "jdbc:postgresql://localhost:5432/mydatabase",
  "myuser",
  "mypassword"
)

val query = sql"SELECT id, json FROM mydata".query[MyData]

val result: IO[List[MyData]] = query
  .stream
  .transact(xa)
  .compile
  .toList

val jsonData: List[Json] = result.map(_.map(_.json)).unsafeRunSync()

val parsedData: List[Either[Error, MyData]] = jsonData.map(parse(_).flatMap(_.as[MyData]))