Here is the request that i am sending as multipart setting files and plain text params.

suspend fun updateUserProfileInformation(
        docList: List<File>,
        type: String?,
        reason: String?,
        address: String?,
        requiredOtp: String?
    ): CommonOtpRes {
        val formData = formData {
            for (file in docList) {
                this.appendInput(
                    key = "documents",
                    headers = Headers.build {
                        append("Content-Type", "image/jpeg")
                        append(HttpHeaders.ContentLength, file.length())
                        append(HttpHeaders.ContentDisposition, "filename=${file.name}")
                    },
                    size = file.length()
                ) { buildPacket { writeFully(file.readBytes()) } }
            }
            append("type", type ?: "")
            append("reason", reason ?: "")
            if(!address.isNullOrEmpty())
                append("address", address)
            if(!requiredOtp.isNullOrEmpty())
                append("requiredOTPS", requiredOtp)
        }
        val response: HttpResponse = client.post("$VERSION/user-request/submit") {
            setBody(
                MultiPartFormDataContent(
                    formData
                )
            )
        }
        return response.body()
    }

Now what i need to do is once that gets called and response is received i need to check that whether some specific status code is received then i need to modify the request and resend it with updated parameters cloning the previous request body and adding additional type param to it. I am receiving the request.body type as the StreamRequestBody type now this class is internal and not directly accessible, so need to find a way to modify the content and resend it with new additional params.

Debug request body

What i have tried so far, original is the request from inside the interceptor once the response is received.

if(original.body is RequestBody && original.body?.isOneShot() == true) {
                val buffer = Buffer()
                original.body?.writeTo(buffer)
                val bodyString = buffer.readUtf8()
                Timber.e("Body Contents: $bodyString")
}

But here the content received is empty.

Previously with Retrofit this was how i had achieved the same but with ktor that is not possible somehow.

val builder: MultipartBody.Builder = MultipartBody.Builder()
                    .setType(MultipartBody.FORM)
                val requestBody = original.body as MultipartBody
                for (part in requestBody.parts) {
                    if (part.body.contentType() == "application/json; charset=utf-8".toMediaTypeOrNull() && part.headers?.get(
                            "Content-Disposition"
                        )?.contains("type") == true
                    ) {
                        builder.addFormDataPart("type", Gson().toJson(list))
                    } else {
                        builder.addPart(part)
                    }
                }
                val multipartReq = original.newBuilder()
                    .method(original.method, builder.build())
                    .build()
                return multipartReq