curl --request GET \
  --url https://api.example.com/invoices/settings \
  --header 'x-digest-key: <api-key>' \
  --header 'x-digest-signature: <x-digest-signature>' \
  --header 'x-digest-timestamp: <x-digest-timestamp>'

import requests

url = "https://api.example.com/invoices/settings"

headers = {
    "x-digest-timestamp": "<x-digest-timestamp>",
    "x-digest-key": "<api-key>",
    "x-digest-signature": "<x-digest-signature>"
}

response = requests.get(url, headers=headers)

print(response.text)

const options = {
  method: 'GET',
  headers: {
    'x-digest-timestamp': '<x-digest-timestamp>',
    'x-digest-key': '<api-key>',
    'x-digest-signature': '<x-digest-signature>'
  }
};

fetch('https://api.example.com/invoices/settings', 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.example.com/invoices/settings",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "GET",
  CURLOPT_HTTPHEADER => [
    "x-digest-key: <api-key>",
    "x-digest-signature: <x-digest-signature>",
    "x-digest-timestamp: <x-digest-timestamp>"
  ],
]);

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

curl_close($curl);

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

package main

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

func main() {

	url := "https://api.example.com/invoices/settings"

	req, _ := http.NewRequest("GET", url, nil)

	req.Header.Add("x-digest-timestamp", "<x-digest-timestamp>")
	req.Header.Add("x-digest-key", "<api-key>")
	req.Header.Add("x-digest-signature", "<x-digest-signature>")

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

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

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.get("https://api.example.com/invoices/settings")
  .header("x-digest-timestamp", "<x-digest-timestamp>")
  .header("x-digest-key", "<api-key>")
  .header("x-digest-signature", "<x-digest-signature>")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.example.com/invoices/settings")

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

request = Net::HTTP::Get.new(url)
request["x-digest-timestamp"] = '<x-digest-timestamp>'
request["x-digest-key"] = '<api-key>'
request["x-digest-signature"] = '<x-digest-signature>'

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

{
  "invoice_prefix": "INV-{year}-",
  "next_number": 5,
  "preview": "INV-2026-5"
}

{
  "reason": "Signature verification failed",
  "statusCode": 401
}

{
  "reason": "Not found",
  "statusCode": 404
}