MultiPartFormDataContent(
    formData {
        var index = 1
        attachments.forEach {
            this.append(key = "file$index", value = it.bytes, headers = Headers.build {
                append(
                    HttpHeaders.ContentDisposition,
                    "filename=${it.fileName}"
                )
            })
            index++
        }
        this.append("payload_json", buildJsonObject {
            putJsonObject(buildJson().toJsonObject())
        }.toString(), headers = buildHeaders {
            append(HttpHeaders.ContentType, "application/json")
        })
    })