Example implementation of useTransactionIdCapturingDispatcher to configure transaction id forwarding

UseTransactionIdCapturingDispatcher.kt

import okhttp3.Dispatcher
import okhttp3.OkHttpClient
import org.slf4j.MDC
import java.util.concurrent.ExecutorService
import java.util.concurrent.Executors

public fun OkHttpClient.Builder.useTransactionIdCapturingDispatcher(
    executorService: ExecutorService = Executors.newCachedThreadPool()
): OkHttpClient.Builder = dispatcher(
    Dispatcher(TransactionContextCapturingExecutorService(executorService))
).addInterceptor {
    val requestBuilder = it.request().newBuilder()
    val transactionId = MDC.get("transaction_id")

    if (requestId != null) {
        requestBuilder.addHeader("x-cp-transaction-id", transactionId)
    }
    it.proceed(requestBuilder.build())
}