X Signature Gen Test : https://developer.x.com/en/docs/authentication/oauth-1-0a/creating-a-signature

Sample.kt

import org.apache.commons.codec.digest.HmacAlgorithms
import org.apache.commons.codec.digest.HmacUtils
import kotlin.io.encoding.Base64
import kotlin.io.encoding.ExperimentalEncodingApi

// Guide : https://developer.x.com/en/docs/authentication/oauth-1-0a/creating-a-signature
@OptIn(ExperimentalStdlibApi::class, ExperimentalEncodingApi::class)
fun main() {
    val baseString =
        "POST&https%3A%2F%2Fapi.x.com%2F1.1%2Fstatuses%2Fupdate.json&include_entities%3Dtrue%26oauth_consumer_key%3Dxvz1evFS4wEEPTGEFPHBog%26oauth_nonce%3DkYjzVBB8Y0ZFabxSWbWovY3uYSQ2pTgmZeNu2VS4cg%26oauth_signature_method%3DHMAC-SHA1%26oauth_timestamp%3D1318622958%26oauth_token%3D370773112-GmHxMAgYyLbNEtIKZeRNFsMKPR9EyMZeS9weJAEb%26oauth_version%3D1.0%26status%3DHello%2520Ladies%2520%252B%2520Gentlemen%252C%2520a%2520signed%2520OAuth%2520request%2521"
    val signingKey = "kAcSOqF21Fu85e7zjz7ZN2U4ZRhfV3WpwPAoE3Z7kBw&LswwdoUaIvS8ltyTt5jkRh4J50vUPVVHtR2YPi5kE"
    val byteString = HmacUtils(HmacAlgorithms.HMAC_SHA_1, signingKey).hmac(baseString)
    println("byteString: ${byteString.toHexString()} ")
    println("base64: ${Base64.encode(byteString)} ")
}