个人中心
gpt4 book ai didi

scala - 如何从 Akka HTTP POST 请求中读取 JSON 正文并将最终响应作为 JSON 数组发送

转载 作者：塔克拉玛干 更新时间：2023-11-01 21:21:09 25 4
gpt4 key购买 nike

我是 akka http 的新手。我创建了一个程序来使用 http 发出发布请求，如下所示 -

object MainController {


  def main(args: Array[String]) {
    implicit val system = ActorSystem()
    implicit val materializer = ActorMaterializer()
    implicit val executionContext = system.dispatcher

    val serverSource = Http().bind(interface = "localhost", port = 9000)

    val requestHandler: HttpRequest => HttpResponse = {
      case HttpRequest(GET, Uri.Path("/welcome"), _, _, _) =>
        HttpResponse(entity = HttpEntity(
          ContentTypes.`text/html(UTF-8)`,
          "<html><body>Welcome to API Application</body></html>"))


      case HttpRequest(POST, Uri.Path("/parseData"), _, entity: HttpEntity, _) =>

// Here Need to read request body which is in json format
        println("1 " + new String(entity.getDataBytes()))
        println("2 " + entity.getDataBytes())
// here need to do some calculations and again construct array of json response and send as HttpResponse
        HttpResponse(entity = "PONG!")

      case r: HttpRequest =>
        r.discardEntityBytes() // important to drain incoming HTTP Entity stream
        HttpResponse(404, entity = "Unknown resource!")
    }

    val bindingFuture = Http().bindAndHandleSync(requestHandler, "localhost", 9000)
    println(s"Server online at http://localhost:8080/\nPress RETURN to stop...")
    StdIn.readLine() // let it run until user presses return
    bindingFuture
      .flatMap(_.unbind()) // trigger unbinding from the port
      .onComplete(_ => system.terminate()) // and shutdown when done

  }
}

正如我在“Post”请求中上面的代码中提到的，我需要读取作为 json 数组的请求正文数据并进行一些计算，最后将处理后的 json 数组发送到 HTTPResponse。甚至还尝试了高级 API，但它再次陷入编码。任何人都可以解释或帮助我吗？

我尝试了另一种方法如下-

object MainController {

  // needed to run the route
  implicit val system = ActorSystem()
  implicit val materializer = ActorMaterializer()
  implicit val executionContext = system.dispatcher

  final case class hexRecord(hexstring: String)
  final case class DeviceData(hexData: List[hexRecord])
  // formats for unmarshalling and marshalling

  implicit val contentFormat = jsonFormat1(hexRecord)
  implicit val dataFormat = jsonFormat1(DeviceData)

  def main(args: Array[String]) {

    implicit val formats = org.json4s.DefaultFormats

    val requestBody = List.empty[Map[String, Any]]
    val route: Route =
      concat(
        get {
          path("welcome"){
          complete("Welcome to Parsing Application")}
        },
        post {
          path("parseDeviceData") {
            entity(as[DeviceData]) { data => {
              val result = data.hexData.map(row => {
                val parseData = ParserManager(Hex.decodeHex(row.hexstring.replaceAll("\\s", "").toCharArray))
               val jsonString = Serialization.writePretty(parseData)
                jsonString

              }).toArray 

              complete(result)
            }
            }
          }
        }
      )

    val bindingFuture = Http().bindAndHandle(route, "localhost", 9000)
    println(s"Server online at http://localhost:9000/")
    StdIn.readLine() // let it run until user presses return
    bindingFuture
      .flatMap(_.unbind()) // trigger unbinding from the port
      .onComplete(_ => system.terminate()) // and shutdown when done
  }
}

这里的结果很好，但我在输出中得到了转义字符 -

[
    " {\n  \"totalsize\" : 128,\n  \"devicetypeuno\" : \"2\"} ",
    " {\n  \"totalsize\" : 128,\n  \"devicetypeuno\" : \"2\"} "
]

最佳答案

这是一个示例程序，它读取一个 json 值数组并返回一个新的 json。 

import akka.actor.ActorSystem
import akka.http.scaladsl.Http
import akka.http.scaladsl.server.Directives._
import akka.stream.ActorMaterializer
import akka.util.Timeout
import de.heikoseeberger.akkahttpcirce.FailFastCirceSupport
import io.circe.generic.semiauto
import io.circe.{Decoder, Encoder}

import scala.concurrent.duration._
import scala.io.StdIn

object WebServer3 extends FailFastCirceSupport {

  def main(args: Array[String]) {

    implicit val system = ActorSystem("my-system")
    implicit val materializer = ActorMaterializer()
    implicit val executionContext = system.dispatcher

    implicit val timeout: Timeout = 2.seconds
    case class Zoo(foo: String, bar: String)
    case class DoneZoo(message: String)
    implicit val zooDecoder: Decoder[Zoo] = semiauto.deriveDecoder[Zoo]
    implicit val zooEncoder: Encoder[Zoo] = semiauto.deriveEncoder[Zoo]
    implicit val doneDecoder: Decoder[DoneZoo] = semiauto.deriveDecoder[DoneZoo]
    implicit val doneEnecoder: Encoder[DoneZoo] =
      semiauto.deriveEncoder[DoneZoo]

    val route = path("parseData") {
      entity(as[List[Zoo]]) { zoo =>
        zoo.foreach(println)
        complete(DoneZoo(zoo.foldLeft("") {
          case (agg, el) => agg + el.bar + el.foo + ";"
        }))
      }
    }

    val bindingFuture = Http().bindAndHandle(route, "localhost", 8080)
    println(s"Server online at http://localhost:8080/\nPress RETURN to stop...")
    StdIn.readLine()
    val _ = bindingFuture.flatMap(_.unbind())
  }
}

json 是在案例类和circe semi auto derivation 的帮助下定义的.这将创建用于 json 转换的编码器/解码器类。您必须将这些类型转换为用于实体编码的 Akka 特定类型，这是在 de.heikoseeberger.akkahttpcirce.FailFastCirceSupport 的帮助下隐式完成的。

在此之后，您可以使用 akka route dsl定义您的 http 路由。 entity(as[List[Zoo]]) 将 http 主体读取为 json 并返回 List[Zoo]

您可以借助 curl

测试此应用 
curl -v -X POST -H 'Content-type: application/json' --data '[{"foo": "Foo", "bar": "Bar"}]' http://localhost:8080/parseData

Note: Unnecessary use of -X or --request, POST is already inferred.
*   Trying ::1...
* TCP_NODELAY set
* Connection failed
* connect to ::1 port 8080 failed: Connection refused
*   Trying 127.0.0.1...
* TCP_NODELAY set
* Connected to localhost (127.0.0.1) port 8080 (#0)
> POST /parseData HTTP/1.1
> Host: localhost:8080
> User-Agent: curl/7.64.1
> Accept: */*
> Content-type: application/json
> Content-Length: 30
>
* upload completely sent off: 30 out of 30 bytes
< HTTP/1.1 200 OK
< Server: akka-http/10.1.7
< Date: Tue, 15 Oct 2019 08:46:56 GMT
< Content-Type: application/json
< Content-Length: 18
<
* Connection #0 to host localhost left intact
{"message":"DONE"}* Closing connection 0

编辑:

Json 序列化必须留给 akka 在指令 entity(as[]) 中处理请求和 complete 响应。不要手动创建 JSON。

关于scala - 如何从 Akka HTTP POST 请求中读取 JSON 正文并将最终响应作为 JSON 数组发送，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/58390371/

25 4 0
文章推荐： ios - react native ListView 问题
文章推荐： android - 检测按下 Android 上的耳机按钮？
文章推荐： ios - 在 iOS 中保持应用程序空闲一段时间后，SRWebsocket 连接自动关闭
文章推荐： ios - 名称中的 React native 图像变量不起作用
塔克拉玛干
个人简介

我是一名优秀的程序员,十分优秀！

滴滴打车优惠券免费领取
滴滴打车优惠券
Copyright 2021 - 2024 cfsdn All Rights Reserved 蜀ICP备2022000587号
广告合作:1813099741@qq.com 6ren.com