Retrofit POST nested object

Question

i want to ask a question about using Retrofit 2 POST with Kotlin

this is the input that Postman does

"assets": {
       "product": [
            {
                "eTag": "\"a59d9f11f3bfc643b00a96cabb8127a6\"",
                "location": "https---abc.com/abc.png",
                "filename": "abc",
                "type": "PD"
            },
            {
                "eTag": "\"dd74783c22bdb8c7cf5ff0185297ee06\"",
                "location": "https---abc.com/abc.png",
                "filename": "abc",
                "type": "PD"
            }
       ],
       "barcode": [
           {
                "eTag": "\"3a4a0719d5fb9f5a1e4b6b9d246db4de\"",
                "location": "https---abc.com/abc.png",
                "filename": "abc",
                "type": "BC"
            }
       ]
   }

this is from my interface

    @FormUrlEncoded
    @POST("create/newassets")
    fun newAssets(
        @Field("assets") assets: Asset? = null,
    ): Call<NewSkuResponse>

this is from my class assets

data class Asset(

    @field:SerializedName("product")
    var product: MutableList<DataItemAsset?>,

    @field:SerializedName("barcode")
    var barcode: MutableList<DataItemAsset?>
)

i got 400 bad request with it, i think my code not working fine any help, thank you

Answer 1

Solved by Oeganz,

It works like a charm with @Body

 fun newAssets(
        @Body reqSKU: ReqSKU,
 ): Call<NewSkuResponse>

data class ReqSKU(
    @SerializedName("assets")
    val assets: Asset
)

data class Asset(

    @field:SerializedName("product")
    var product: MutableList<DataItemAsset?>,

    @field:SerializedName("barcode")
    var barcode: MutableList<DataItemAsset?>
)