data-classes.kt

data class Contract private constructor(
    val request: Request, 
    val response: Response
) {

    class Builder {
        var request = Request.Builder()
        var response = Response.Builder()

        fun build(): Contract {
            return Contract(request.build(), response.build())
        }
    }
}

class Request private constructor(
        val path: String,
        val method: HttpMethod,
        val body: String?,
        val headers: HttpHeaders
) {
    class Builder {
        var path = ""
        var method = HttpMethod.GET
        var body: String? = null
        var expect = Response.Builder()
        var headers = HttpHeaders()

        fun build(): Request {
            return Request(path, method, body?.trimIndent(), headers)
        }
    }
}

class Response private constructor(
        val status: HttpStatus,
        val body: String?
) {
    class Builder {
        var status = HttpStatus.OK
        var body: String? = null

        fun build(): Response {
            return Response(status, body?.trimIndent())
        }
    }
}