const axios = require('axios');
const fs = require('fs');
const FilesApiFp = require('@alohi/faxplus-api').FilesApiFp;
const Configuration = require('@alohi/faxplus-api').Configuration;

const config = new Configuration({
    accessToken: accessToken,
    basePath: 'https://restapi.fax.plus/v3',
    // Header required only when using the OAuth2 token scheme
    baseOptions: {
        headers: {
          "x-fax-clientid": clientId,
        }
    }
});

async function uploadFile() {
    // IMPORTANT: fs.createReadStream() requires a local file system path.
    // It does NOT support URLs or remote streams.
    // 
    // If your file is stored remotely (e.g., AWS S3, Google Cloud Storage, or HTTP URL),
    // you must first download it to a local path or load it into memory as a Blob.
    const reqParams = {
        "userId": '13d8z73c',
        "faxFile": fs.createReadStream(FILE_PATH)  // FILE_PATH must be a local file path
    }
    const req = await FilesApiFp(config).uploadFile(reqParams);
    const resp = await req(axios);
}

uploadFile()

from faxplus import ApiClient, FilesApi
from faxplus.configuration import Configuration

conf = Configuration()
conf.access_token = access_token
# header_name and header_value required only when using the OAuth2 token scheme
api_client = ApiClient(header_name='x-fax-clientid', header_value=client_id, configuration=conf)
api = FilesApi(api_client)
resp = api.upload_file(
    user_id='13d8z73c',
    fax_file='/path/to/file.pdf'
)

/**
 * Example below uses Apache HTTP Client 4 with Fluent API
 **/

Map<String, String> pathParams = new HashMap<>();
pathParams.put("user_id", "'13d8z73c'");

StrSubstitutor sub = new StrSubstitutor(values, "{", "}");
String url = sub.replace("https://restapi.fax.plus/v3/accounts/{user_id}/files");

HttpEntity entity = MultipartEntityBuilder.create()
        .setMode(HttpMultipartMode.BROWSER_COMPATIBLE)
        .setCharset(Charset.forName(CHARSET))
        .addBinaryBody("fax_file", bytes, ContentType.MULTIPART_FORM_DATA, "fax.pdf")
        .build();

String result = Request
    .Post(url)
     // The x-fax-clientid header is required only when using the OAuth2 token scheme
    .addHeader("x-fax-clientid", "YOUR CLIENT_ID")
    .addHeader("Content-Type", "'multipart/form-data'")
    .addHeader("Accept", "'application/json'")
    .addHeader("Authorization", "'Bearer {access-token}'")
    .body(entity)
    .execute()
    .returnContent().asString();

System.out.println(result.toString());

package main

import (
       "bytes"
       "net/http"
)

func main() {

    headers := map[string][]string{
        // The x-fax-clientid header is required only when using the OAuth2 token scheme
        "Content-Type": []string{"multipart/form-data"},
        "Accept": []string{"application/json"},
        "Authorization": []string{"Bearer {access-token}"},
        "x-fax-clientid": []string{"YOUR CLIENT_ID"}
    }

    body := &bytes.Buffer{}
    writer := multipart.NewWriter(body)
    fax_file_part, err := writer.CreateFormFile('fax_file', filepath.Base('fax.pdf'))
    _, err = io.Copy(part, file)

    req, err := http.NewRequest("POST", "https://restapi.fax.plus/v3/accounts/{user_id}/files", data)
    req.Header = headers

    client := &http.Client{}
    resp, err := client.Do(req)
    // ...
}

<?php

require 'vendor/autoload.php';

$headers = array(
    'Accept' => 'application/json',
    'Authorization' => 'Bearer {access-token}',
    // The x-fax-clientid header is required only when using the OAuth2 token scheme
    'x-fax-clientid' => '{client ID}',
);

$client = new GuzzleHttp\Client();

try {
    $response = $client->request('POST','https://restapi.fax.plus/v3/accounts/{user_id}/files', array(
        'headers' => $headers,
        'multipart' => [
          [
            'name' => 'fax_file',
            'contents' => fopen('fax.pdf', 'r')
          ],
        ],)
    );
    print_r($response->getBody()->getContents());
 }
 catch (GuzzleHttp\Exception\BadResponseException $e) {
    // handle exception or api errors.
    print_r($e->getMessage());
 }

 // ...

# You can also use wget
curl -X POST https://restapi.fax.plus/v3/accounts/{user_id}/files \
  -H 'Content-Type: multipart/form-data'  \
  -H 'Accept: application/json'  \
  -H 'Authorization: Bearer {access-token}' \
  # The x-fax-clientid header is required only when using the OAuth2 token scheme
  -H 'x-fax-clientid: "YOUR CLIENT_ID"' \
  -F 'fax_file=@fax.pdf'