How to get list from response in kotlin-CodePudding

I have this api that returns a list as response

Here's the API https://animension.to/public-api/search.php?search_text=&season=&genres=&dub=&airing=&sort=popular-week&page=2

this returns a response string in list format like this

[["item", 1, "other item"], ["item", 2, "other item"]]

How do I convert this so that I can use it as list not string data type

CodePudding user response：

One way is to use Kotlinx Serialization. It doesn't have direct support for tuples, but it's easy to parse the input as a JSON array, then manually map to a specific data type (if we make some assumptions).

First add a dependency on Kotlinx Serialization.

// build.gradle.kts

plugins {
  kotlin("jvm") version "1.7.10"
  kotlin("plugin.serialization") version "1.7.10" 
  // the KxS plugin isn't needed, but it might come in handy later!
}

dependencies {
  implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.4.0")
}

(See the Kotlinx Serialization README for Maven instructions.)

Then we can use the JSON mapper to parse the result of the API request.

import kotlinx.serialization.json.*

fun main() {
  val inputJson = """ 
     [["item", 1, "other item"], ["item", 2, "other item"]]
  """.trimIndent()

  // Parse, and use .jsonArray to force the results to be a JSON array
  val parsedJson: JsonArray = Json.parseToJsonElement(inputJson).jsonArray

  println(parsedJson)
  // [["item",1,"other item"],["item",2,"other item"]]
}

It's much easier to manually map this JsonArray object to a data class than it is to try and set up a custom Kotlinx Serializer.

import kotlinx.serialization.json.*

fun main() {
  val inputJson = """ 
     [["item", 1, "other item"], ["item", 2, "other item"]]
  """.trimIndent()

  val parsedJson: JsonArray = Json.parseToJsonElement(inputJson).jsonArray

  val results = parsedJson.map { element ->
    val data = element.jsonArray
    // Manually map to the data class. 
    // This will throw an exception if the content isn't the correct type...
    SearchResult(
      data[0].jsonPrimitive.content, 
      data[1].jsonPrimitive.int,
      data[2].jsonPrimitive.content,
    )
  }

  println(results)
  // [SearchResult(title=item, id=1, description=other item), SearchResult(title=item, id=2, description=other item)]

}

data class SearchResult(
  val title: String,
  val id: Int,
  val description: String,
)

The parsing I've defined is strict, and assumes each element in the list will also be a list of 3 elements.