为了实现ReSTfull API堆栈,我需要将从数据库中提取的数据转换为JSON格式。我认为最好的方法是从数据库中提取数据,然后使用Json.toJson()将行集转换为JSON,在定义了隐式序列化程序(写入)之后作为参数传递一个case类。
这是我的案例类和伴侣对象:
package deals.db.interf.slick2
import scala.slick.driver.MySQLDriver.simple._
import play.api.libs.json.Json
case class PartnerInfo(
id: Int,
name: String,
site: String,
largeLogo: String,
smallLogo: String,
publicationSite: String
)
object PartnerInfo {
def toCaseClass( ?? ) = { // what type are the arguments to be passed?
PartnerInfo( fx(??) ) // how to transform the input types (slick) to Scala types?
}
// Notice I'm using slick 2.0.0 RC1
class PartnerInfoTable(tag: Tag) extends Table[(Int, String, String, String, String, String)](tag, "PARTNER"){
def id = column[Int]("id")
def name = column[String]("name")
def site = column[String]("site")
def largeLogo = column[String]("large_logo")
def smallLogo = column[String]("small_logo")
def publicationSite = column[String]("publication_site")
def * = (id, name, site, largeLogo, smallLogo, publicationSite)
}
val partnerInfos = TableQuery[PartnerInfoTable]
def qPartnerInfosForPuglisher(publicationSite: String) = {
for (
pi <- partnerInfos if ( pi.publicationSite == publicationSite )
) yield toCaseClass( _ ) // Pass all the table columns to toCaseClass()
}
implicit val partnerInfoWrites = Json.writes[PartnerInfo]
}
我不能得到的是如何实现toCaseClass()方法以便将列类型从Slick 2转换为Scala类型 - 请注意toCaseClass()体中的函数fx()仅用于强调这一点。
我想知道是否有可能从Slick列类型中获取Scala类型,因为它明确地在表定义中传递,但我找不到如何获取它。
有什么想法吗?
答案 0 :(得分:9)
我认为这里最简单的方法是在表架构中映射PartnerInfo
:
class PartnerInfoTable(tag: Tag) extends Table[PartnerInfo](tag, "PARTNER"){
def id = column[Int]("id")
def name = column[String]("name")
def site = column[String]("site")
def largeLogo = column[String]("large_logo")
def smallLogo = column[String]("small_logo")
def publicationSite = column[String]("publication_site")
def * = (id, name, site, largeLogo, smallLogo, publicationSite) <> (PartnerInfo.tupled, PartnerInfo.unapply)
}
val partnerInfos = TableQuery[PartnerInfoTable]
def qPartnerInfosForPuglisher(publicationSite: String) = {
for (
pi <- partnerInfos if ( pi.publicationSite == publicationSite )
) yield pi
}
否则,PartnerInfo.tupled应该可以解决问题:
def toCaseClass(pi:(Int, String, String, String, String, String)) = PartnerInfo.tupled(pi)