Authentication

The API supports three authentication methods. For production integrations, use an API key — optionally with HMAC request signing.

Method	Best for	Header(s)
API key	Production integrations	X-API-Key
API key + HMAC	High-security environments	X-API-Key, X-Timestamp, X-Signature
JWT token	Testing, portal-only endpoints	Authorization: Bearer …

API key (recommended)

Create keys in the portal under Settings → API Keys (see API keys & permissions). Pass the key in the X-API-Key header with every request:

X-API-Key: sk_prod_a1b2c3d4e5f6g7h8i9j0...

cURL

curl "https://restlink23telecom.com/api/v1/sms/stats?period=7d" \
  -H "X-API-Key: $API_KEY"

Node.js

const res = await fetch('https://restlink23telecom.com/api/v1/sms/stats?period=7d', {
  method: 'GET',
  headers: { 'X-API-Key': process.env.API_KEY },
});

if (!res.ok) {
  const err = await res.json();
  throw new Error(`${err.error_code}: ${err.description}`);
}
const data = await res.json();
console.log(data);

Python

import os
import requests

res = requests.get(
    "https://restlink23telecom.com/api/v1/sms/stats",
    headers={"X-API-Key": os.environ["API_KEY"]},
    params={
        "period": "7d"
    },
)
res.raise_for_status()
print(res.json())

PHP

<?php
$ch = curl_init('https://restlink23telecom.com/api/v1/sms/stats?period=7d');
curl_setopt_array($ch, [
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_HTTPHEADER     => ['X-API-Key: ' . getenv('API_KEY')],
]);

$response = curl_exec($ch);
$status   = curl_getinfo($ch, CURLINFO_HTTP_CODE);
curl_close($ch);

if ($status !== 200) {
    throw new Exception("HTTP $status: $response");
}
$data = json_decode($response, true);
print_r($data);

Ruby

require "net/http"
require "json"

uri = URI("https://restlink23telecom.com/api/v1/sms/stats?period=7d")
req = Net::HTTP::Get.new(uri)
req["X-API-Key"] = ENV.fetch("API_KEY")

res = Net::HTTP.start(uri.hostname, uri.port, use_ssl: true) { |http| http.request(req) }
raise "HTTP #{res.code}: #{res.body}" unless res.is_a?(Net::HTTPSuccess)

puts JSON.parse(res.body)

Java

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;

HttpClient client = HttpClient.newHttpClient();

HttpRequest request = HttpRequest.newBuilder()
    .uri(URI.create("https://restlink23telecom.com/api/v1/sms/stats?period=7d"))
    .header("X-API-Key", System.getenv("API_KEY"))
    .GET()
    .build();

HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());
System.out.println(response.body());

Go

package main

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

func main() {
  req, err := http.NewRequest("GET", "https://restlink23telecom.com/api/v1/sms/stats?period=7d", nil)
  if err != nil {
    panic(err)
  }
  req.Header.Set("X-API-Key", os.Getenv("API_KEY"))

  res, err := http.DefaultClient.Do(req)
  if err != nil {
    panic(err)
  }
  defer res.Body.Close()

  data, _ := io.ReadAll(res.Body)
  fmt.Println(string(data))
}

.NET

using System.Text;

using var client = new HttpClient();
client.DefaultRequestHeaders.Add("X-API-Key",
    Environment.GetEnvironmentVariable("API_KEY"));

var response = await client.GetAsync("https://restlink23telecom.com/api/v1/sms/stats?period=7d");

response.EnsureSuccessStatusCode();
Console.WriteLine(await response.Content.ReadAsStringAsync());

Keep keys out of code

Store keys in environment variables or a secrets manager — never commit them to version control. All examples in these docs read the key from the API_KEY environment variable.

API key with HMAC signature

For enhanced security, enable signature verification when creating the key. Every request must then carry three headers:

Header	Description
X-API-Key	Your API key
X-Timestamp	Current Unix timestamp in seconds
X-Signature	HMAC-SHA256 signature (hex)

Signature computation:

message   = "{METHOD}|{path}|{timestamp}|{body}"
signature = HMAC-SHA256(api_secret, message)

Three rules to get it right:

• path is the URL path without the query string — /api/v1/sms/stats, not /api/v1/sms/stats?period=7d.
• body is the raw request body string; use an empty string "" for GET.
• Timestamps must be within 5 minutes of server time, and each timestamp + signature pair is accepted once (replay protection).

Node.js

import crypto from 'node:crypto';

const apiKey = process.env.API_KEY;
const apiSecret = process.env.API_SECRET;

const timestamp = Math.floor(Date.now() / 1000).toString();
const method = 'POST';
const path = '/api/v1/sms/send';
const body = JSON.stringify({
  to: ['+14155551234'],
  message: 'Hello!',
  sender_id: 'MyApp',
});

const signature = crypto
  .createHmac('sha256', apiSecret)
  .update(`${method}|${path}|${timestamp}|${body}`)
  .digest('hex');

const res = await fetch('https://restlink23telecom.com' + path, {
  method,
  headers: {
    'Content-Type': 'application/json',
    'X-API-Key': apiKey,
    'X-Timestamp': timestamp,
    'X-Signature': signature,
  },
  body,
});
console.log(await res.json());

Python

import hmac, hashlib, time, os, requests

api_key    = os.environ["API_KEY"]
api_secret = os.environ["API_SECRET"]

timestamp = str(int(time.time()))
method    = "POST"
path      = "/api/v1/sms/send"
body      = '{"to":["+14155551234"],"message":"Hello!","sender_id":"MyApp"}'

message   = f"{method}|{path}|{timestamp}|{body}"
signature = hmac.new(api_secret.encode(), message.encode(), hashlib.sha256).hexdigest()

res = requests.post(
    "https://restlink23telecom.com" + path,
    headers={
        "Content-Type": "application/json",
        "X-API-Key": api_key,
        "X-Timestamp": timestamp,
        "X-Signature": signature,
    },
    data=body,
)
print(res.json())

PHP

<?php
$apiKey    = getenv('API_KEY');
$apiSecret = getenv('API_SECRET');

$timestamp = (string) time();
$method    = 'POST';
$path      = '/api/v1/sms/send';
$body      = json_encode(['to' => ['+14155551234'], 'message' => 'Hello!', 'sender_id' => 'MyApp']);

$signature = hash_hmac('sha256', "$method|$path|$timestamp|$body", $apiSecret);

$ch = curl_init("https://restlink23telecom.com$path");
curl_setopt_array($ch, [
    CURLOPT_POST           => true,
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_POSTFIELDS     => $body,
    CURLOPT_HTTPHEADER     => [
        'Content-Type: application/json',
        "X-API-Key: $apiKey",
        "X-Timestamp: $timestamp",
        "X-Signature: $signature",
    ],
]);
echo curl_exec($ch);

Go

package main

import (
    "crypto/hmac"
    "crypto/sha256"
    "encoding/hex"
    "fmt"
    "net/http"
    "os"
    "strconv"
    "strings"
    "time"
)

func main() {
    apiKey, apiSecret := os.Getenv("API_KEY"), os.Getenv("API_SECRET")

    timestamp := strconv.FormatInt(time.Now().Unix(), 10)
    method, path := "POST", "/api/v1/sms/send"
    body := `{"to":["+14155551234"],"message":"Hello!","sender_id":"MyApp"}`

    mac := hmac.New(sha256.New, []byte(apiSecret))
    mac.Write([]byte(method + "|" + path + "|" + timestamp + "|" + body))
    signature := hex.EncodeToString(mac.Sum(nil))

    req, _ := http.NewRequest(method, "https://restlink23telecom.com"+path, strings.NewReader(body))
    req.Header.Set("Content-Type", "application/json")
    req.Header.Set("X-API-Key", apiKey)
    req.Header.Set("X-Timestamp", timestamp)
    req.Header.Set("X-Signature", signature)

    res, err := http.DefaultClient.Do(req)
    if err != nil {
        panic(err)
    }
    defer res.Body.Close()
    fmt.Println(res.Status)
}

Signature failures return 401 SIGNATURE_REQUIRED (headers missing) or 401 INVALID_SIGNATURE (verification failed) — see errors.

JWT token

You can also authenticate by logging in with portal credentials. This is mainly useful for testing and for the few endpoints that are JWT-only (for example listing workspaces). For production integrations use API keys.

Log in

curl -X POST https://restlink23telecom.com/api/v1/user/auth \
  -H "Content-Type: application/json" \
  -d '{"login": "your_username", "password": "your_password"}'

200 OK

{
  "status": true,
  "token": "eyJhbGciOiJIUzI1NiIs..."
}

Pass the token in subsequent requests:

Authorization: Bearer eyJhbGciOiJIUzI1NiIs...

Note

Tokens are invalidated when you change or reset your password, or when a token is explicitly revoked. Your integration should handle 401 TOKEN_EXPIRED / 401 INVALID_TOKEN by re-authenticating.