Graphql Sangria多对多示例

case class User(id: Int, name: String, emails: List[Email])
case class Email(id: Int, address: String, users: List[User])

val UserType = ObjectType(
  "User",
  fields[Unit, User](
    Field("id", IntType, resolve = _.value.id),
    Field("name", StringType, resolve = _.value.name),
    Field("emails", ListType(EmailType), resolve = _.value.emails)
  )
)

val EmailType = ObjectType(
  "Email",
  fields[Unit, Email](
    Field("id", IntType, resolve = _.value.id),
    Field("address", StringType, resolve = _.value.address),
    Field("users", ListType(UserType), resolve = _.value.users)
  )
)

val QueryType = ObjectType(
  "Query",
  fields[UserRepo, Unit](
    Field("users", ListType(UserType), resolve = _.ctx.users),
    Field("emails", ListType(EmailType), resolve = _.ctx.emails)
  )
)

val schema = Schema(QueryType)

val userRepo = new UserRepo // 数据库访问对象

val query = graphql"{ users { id name emails { id address } } }"

val result = Executor.execute(schema, query, userRepo)