如何使用lift-json的类提取器构造函数mongo bson数组? [英] How to use lift-json's class extractor constructor mongo bson array?
问题描述
我使用lift-json通过类提取器渲染bson字符串,然后,使用mongo Document
类构造函数使用该bson字符串创建文档实例.
I'm use lift-json render a bson string with class extractor, after that, use mongo Document
class constructor a document instance with that bson string.
一个问题是如何表示$or
bson.这似乎不是经典的json数组.
A problem is how about represent $or
bson.It seems not a classic json array.
{"$or": [
{"username": "administrator"},
{"phone":"110"},
{"email":"123@xxx.com"},
{"pen_name":"lorancechen"}
]}
如何使用Lift类提取器来表示此bson数组?
How to use lift class extractor represent this bson array?
此外,在app和mongo之间使用字符串的原因是它们是在一个简单的套接字下进行通信的.
Besides, the reason of use string between app and mongo is they are communicate under a simple socket.
更新添加示例
提取正常的数组类,如下所示:
UPDATE add a example
extractor a normal array class as follow:
import net.liftweb.json._
import net.liftweb.json.Extraction._
case class Name(name: String)
case class JsonArray(array:List[Name])
object JsonClient extends App {
implicit val formats = DefaultFormats
val names = Name("jone01") :: Name("jone02") :: Nil
val array = JsonArray(names)
val jsonString = prettyRender(decompose(array))
println(jsonString)
}
输出:
{
"array":[
{
"name":"jone01"
},
{
"name":"jone02"
}
]
}
如何表示这一点
{"$or": [
{"username": "administrator"},
{"phone":"110"},
{"email":"123@xxx.com"},
{"pen_name":"lorancechen"}
]}
元素内部"$ or"的每个字段键(例如,username
,phone
)都不是通用键名,我还没有找到使用类模板来表示它的方法.
every field key (eg, username
, phone
) of element inner "$or" is not common key name and I haven't find a way to represent it use class template.
推荐答案
我不明白为什么您的JSON结构是这种方式,也许您想要的是以下内容:
I don't get it why your JSON structure is that way, maybe what you want is the following one:
{
"$or": [
{
"username": "administrator", "phone":"110",
"email":"123@xxx.com", "pen_name":"lorancechen"
},
{
"username": "xxx", "phone":"xxx",
"email":"xxx", "pen_name":"xxx"
}
...
]
}
实际上,Lift提供了这样的工具,缺点是实现起来有点难看.
Actually Lift provides such tools and the downside is that the implementation is a little bit ugly.
import net.liftweb.mongodb.{JsonObjectMeta, JsonObject}
// the trait here is for unifying the type of
//four case classes i.e Username, Phone....
sealed trait PersonField
object Username extends JsonObjectMeta[Username]
case class Username(username: String) extends JsonObject[Username]
with PersonField {
def meta = Username
}
case class Phone(phone: String) extends JsonObject[Phone] with PersonField {
def meta = Phone
}
object Phone extends JsonObjectMeta[Phone]
case class Email(email: String) extends JsonObject[Email] with PersonField {
def meta = Email
}
object Email extends JsonObjectMeta[Email]
case class PenName(pen_name: String) extends JsonObject[PenName]
with PersonField {
def meta = PenName
}
object PenName extends JsonObjectMeta[PenName]
case class Output(`$or`: List[PersonField]) extends JsonObject[Output] {
def meta = Output
}
object Output extends JsonObjectMeta[Output]
object JsonClient extends App {
val username = Username("administrator")
val phone = Phone("110")
val email = Email("123@xxx.com")
val penName = PenName("lorancechen")
val outPut = Output(username :: phone :: email :: penName :: Nil)
import net.liftweb.json._
implicit val formats = DefaultFormats
import net.liftweb.json.{JsonAST, Printer}
val result = Printer.pretty(JsonAST.render(outPut.asJObject))
/*
{
"$or":[{
"username":"administrator"
},{
"phone":"110"
},{
"email":"123@xxx.com"
},{
"pen_name":"lorancechen"
}]
}
*/
println(result)
}
无论如何,希望对您有所帮助.
Anyway, hope it helps.
这篇关于如何使用lift-json的类提取器构造函数mongo bson数组?的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!