curl --request POST \
  --url https://api.lilt.com/v2/documents/files \
  --header 'Authorization: Basic <encoded-value>' \
  --header 'Content-Type: application/octet-stream' \
  --header 'name: <name>' \
  --header 'project_id: <project_id>' \
  --data '<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<xliff xmlns="urn:oasis:names:tc:xliff:document:1.2">
...
</xliff>'

import requests

url = "https://api.lilt.com/v2/documents/files"

payload = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>\n<xliff xmlns=\"urn:oasis:names:tc:xliff:document:1.2\">\n...\n</xliff>"
headers = {
    "name": "<name>",
    "project_id": "<project_id>",
    "Authorization": "Basic <encoded-value>",
    "Content-Type": "application/octet-stream"
}

response = requests.post(url, data=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {
    name: '<name>',
    project_id: '<project_id>',
    Authorization: 'Basic <encoded-value>',
    'Content-Type': 'application/octet-stream'
  },
  body: '<?xml version="1.0" encoding="UTF-8" standalone="no"?>\n<xliff xmlns="urn:oasis:names:tc:xliff:document:1.2">\n...\n</xliff>'
};

fetch('https://api.lilt.com/v2/documents/files', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.lilt.com/v2/documents/files",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>\n<xliff xmlns=\"urn:oasis:names:tc:xliff:document:1.2\">\n...\n</xliff>",
  CURLOPT_HTTPHEADER => [
    "Authorization: Basic <encoded-value>",
    "Content-Type: application/octet-stream",
    "name: <name>",
    "project_id: <project_id>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.lilt.com/v2/documents/files"

	payload := strings.NewReader("<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>\n<xliff xmlns=\"urn:oasis:names:tc:xliff:document:1.2\">\n...\n</xliff>")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("name", "<name>")
	req.Header.Add("project_id", "<project_id>")
	req.Header.Add("Authorization", "Basic <encoded-value>")
	req.Header.Add("Content-Type", "application/octet-stream")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.lilt.com/v2/documents/files")
  .header("name", "<name>")
  .header("project_id", "<project_id>")
  .header("Authorization", "Basic <encoded-value>")
  .header("Content-Type", "application/octet-stream")
  .body("<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>\n<xliff xmlns=\"urn:oasis:names:tc:xliff:document:1.2\">\n...\n</xliff>")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.lilt.com/v2/documents/files")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["name"] = '<name>'
request["project_id"] = '<project_id>'
request["Authorization"] = 'Basic <encoded-value>'
request["Content-Type"] = 'application/octet-stream'
request.body = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>\n<xliff xmlns=\"urn:oasis:names:tc:xliff:document:1.2\">\n...\n</xliff>"

response = http.request(request)
puts response.read_body

{
  "id": 46530,
  "project_id": 287,
  "srclang": "en",
  "trglang": "de",
  "name": "Introduction.xliff",
  "import_in_progress": false,
  "import_succeeded": false,
  "import_error_message": "Could not parse XML.",
  "export_in_progress": false,
  "export_succeeded": false,
  "export_error_message": "Could not parse XML.",
  "is_pretranslating": false,
  "status": {
    "pretranslation": "idle"
  },
  "translator_email": "translator@example.com",
  "reviewer_email": "reviewer@example.com",
  "created_at": 1489147692,
  "updated_at": 1489147692,
  "is_review_complete": true,
  "segments": [
    {
      "id": 84480010,
      "created_at": 1489147692,
      "updated_at": 1489147692,
      "document_id": 1234,
      "memory_id": 5678,
      "source": "The red bus.",
      "srclang": "en",
      "target": "Le bus rouge.",
      "trglang": "fr",
      "is_confirmed": true,
      "is_reviewed": true
    }
  ]
}

"<string>"

{
  "message": "Internal server error."
}