Sanitise/Remove emojis from all requests type before requesting to server

Question

I need to remove emojies from the request body (json type) before sending it to the server, like we can sanitise headers while using Logger. so far I know we can intercept the request like this

      HttpClient {
        ......
        .....
      }.plugin(HttpSend).intercept { request ->
        val originalCall = execute(request)
        val contentType = originalCall.request.content.contentType
        val isJson: Boolean = contentType == ContentType("application", "json")
        if (isJson) {
          //how to find and remove emojis from the body
          //then execute(sanitised request)
        } else {
          originalCall
        }

is there a better way to do this please share thanks

Answer 1

To sanitize the request body you can determine the type of the HttpRequestBuilder.body property and create a new request body with the sanitized content. Here is an example:

import io.ktor.client.*
import io.ktor.client.engine.cio.*
import io.ktor.client.plugins.api.*
import io.ktor.client.plugins.contentnegotiation.*
import io.ktor.client.request.*
import io.ktor.client.statement.*
import io.ktor.content.*
import io.ktor.http.*
import io.ktor.serialization.kotlinx.json.*
import io.ktor.util.*
import kotlinx.serialization.Serializable

@OptIn(InternalAPI::class)
val plugin = createClientPlugin("no-emojis") {
    on(Send) {
        val newBody = when (val body = it.body) {
            is TextContent -> {
                val text = body.text.replace("x", "value") // An example of sanitizing
                TextContent(text, body.contentType, body.status)
            }

            else -> error("I don't know how to sanitize $body")
        }
        it.body = newBody
        proceed(it)
    }
}

@Serializable
data class Some(val x: Int)

suspend fun main() {
    val client = HttpClient(CIO) {
        install(ContentNegotiation) {
            json()
        }
        install(plugin)
    }
    val r = client.post("https://httpbin.org/post") {
        setBody(Some(123))
        contentType(ContentType.Application.Json)
    }
    println(r.bodyAsText())
}