Error Could Not Implicit Value ToResponseMarshaller[SearchResponse] - json

Question

what i want to achieve are : create an API, which looking for into ElasticSearch. my programming language is Scala.
//myRoute.scala
val pencarianES =
{
post
{
path("cariES")
{
parameters("xQuery", "xNilai")
{
(yQuery, yNilai) =>
val PR = new ProsesRekomendasi
respondWithMediaType(MediaTypes.`application/json`)
{
complete
{
PR.ambilDariES(yQuery, yNilai)
}
}
}
}
}
}
//prosesRekomendasi.scala
class ProsesRekomendasi
{
val ESM = new ESManager
val CLT = ESM.client
def ambilDariES(pQuery:String, pNilai:String) =
{
CLT.prepareSearch("app_lr_portal_01")
.setTypes("lr01")
.setQuery(QueryBuilders.termQuery(s"$pQuery",s"$pNilai"))
.execute()
.actionGet()
}
}
the error are :
could not find implicit value for parameter marshaller:
spray.httpx.marshalling.ToResponseMarshaller[org.eleasticsearch.action.search.SearchResponse]
PR.ambilDariES(yQuery, yNilai)
i was looking for at google, and founded
DefaultMarshallers missing with scala and spray-routing
and then, im follow the instructions :
def ambilDariES(pQuery:String, pNilai:String)(implicit ec:ExecutionContext) =
{
CLT.prepareSearch("app_lr_portal_01")
.setTypes("lr01")
.setQuery(QueryBuilders.termQuery(s"$pQuery",s"$pNilai"))
.execute()
.actionGet()
}
finally, i get another error which are :
Cannot find an implicit ExecutionContext, either import scala.concurrent.ExecutionContext.Implicits.global or use a custom one
PR.ambilDariES(yQuery, yNilai)
any idea, how to deal with that? thanks for your help!

Answer 1

Although building RootJsonFormat for java classes is very tedious, here one example for one result. Just import in scope:
object SearchResultProtocol {
implicit object SearchResulJsonFormatObject extends RootJsonFormat[SearchResponse] {
def read(e: JsValue) = null
/* {
"_shards":{
"total" : 5,
"successful" : 5,
"failed" : 0
},
"hits":{
"total" : 1,
"hits" : [
{
"_index" : "twitter",
"_type" : "tweet",
"_id" : "1",
"_source" : {
"user" : "kimchy",
"postDate" : "2009-11-15T14:12:12",
"message" : "trying out Elasticsearch"
}
}
]
}
}*/
private def getHits(arr: Array[SearchHit]) : JsArray = {
JsArray(arr.map { x => marshallHit(x) }.toVector)
}
private def marshallHit(hit: SearchHit) : JsValue = {
JsObject(Map("_index" -> JsString(hit.index()),
"_type" -> JsString(hit.getType),
"_id" -> JsString(hit.getId),
"source" -> JsString(hit.getSourceAsString)))
}
def write(sr: SearchResponse) = {
JsObject(Map("_shards" ->
JsObject(Map("total" -> JsNumber(sr.totalShards()),
"successful" -> JsNumber(sr.getSuccessfulShards()),
"failed" -> JsNumber(sr.getFailedShards()))),
"hits" -> JsObject(Map("total" -> JsNumber(sr.getHits.totalHits()),
"" -> getHits(sr.getHits.getHits)
))))
}
}
}