Send a WhatsApp message with PHP

<?php
// PHP 8+ with the built-in cURL extension — no Composer packages needed.
const LP_BASE_URL = 'https://public.leadpattern.com';
$apiKey = getenv('LEADPATTERN_API_KEY'); // YOUR_API_KEY — keep it on the server

/** POST JSON to the Lead Pattern API and return [status, decoded body, Retry-After]. */
function lp_post(string $path, array $payload, string $apiKey): array
{
    $retryAfter = null;
    $ch = curl_init(LP_BASE_URL . $path);
    curl_setopt_array($ch, [
        CURLOPT_POST           => true,
        CURLOPT_RETURNTRANSFER => true,
        CURLOPT_TIMEOUT        => 30,
        CURLOPT_HTTPHEADER     => [
            'Authorization: ' . $apiKey, // the raw key, NO "Bearer " prefix
            'Content-Type: application/json',
        ],
        CURLOPT_POSTFIELDS     => json_encode($payload),
        CURLOPT_HEADERFUNCTION => function ($ch, $line) use (&$retryAfter) {
            if (stripos($line, 'Retry-After:') === 0) {
                $retryAfter = (int) trim(substr($line, 12));
            }
            return strlen($line);
        },
    ]);
    $raw = curl_exec($ch);
    if ($raw === false) {
        throw new RuntimeException('Network error: ' . curl_error($ch));
    }
    $status = curl_getinfo($ch, CURLINFO_RESPONSE_CODE);
    curl_close($ch);
    return [$status, json_decode($raw, true), $retryAfter];
}

class LeadPatternException extends RuntimeException
{
    public function __construct(public int $status, public $body, public ?int $retryAfter = null)
    {
        parent::__construct('HTTP ' . $status . ': ' . json_encode($body));
    }
}

function lp_handle(array $res): array
{
    [$status, $body, $retryAfter] = $res;
    if ($status === 201) {
        return $body['data']; // ['messageId' => ...] or ['messages' => [...]]
    }
    // e.g. ['type' => 'error', 'code' => 403, 'message' => '...']
    throw new LeadPatternException($status, $body, $retryAfter);
}

<?php
function send_template(string $to, string $name, string $language, array $placeholders, string $apiKey): array
{
    $payload = [
        'messages' => [[
            'to'      => $to, // E.164 with country code, e.g. "+91XXXXXXXXXX"
            'content' => [
                'templateName' => $name,
                'language'     => $language,
                'templateData' => ['body' => ['placeholders' => $placeholders]],
            ],
        ]],
    ];
    return lp_handle(lp_post('/v2/whatsapp/message/template', $payload, $apiKey));
}

$data = send_template('+91XXXXXXXXXX', 'order_confirmation', 'en',
    [['name' => 'Customer'], ['order_id' => 'ORD-1234']], $apiKey);
echo $data['messages'][0]['messageId'];

{
  "type": "success",
  "data": {
    "messages": [
      {
        "status": "SENT",
        "recipient": "91XXXXXXXXXX",
        "messageId": "wamid.abc123"
      }
    ]
  }
}

<?php
// Free-form text — only works within 24 hours of the customer's last message.
function send_text(string $to, string $text, string $apiKey, bool $previewUrl = false): array
{
    $payload = ['to' => $to, 'content' => ['text' => $text, 'previewUrl' => $previewUrl]];
    return lp_handle(lp_post('/whatsapp/message/text', $payload, $apiKey));
}

echo send_text('+91XXXXXXXXXX', 'Hello! How can I help you?', $apiKey)['messageId'];

{
  "type": "success",
  "data": {
    "messageId": "wamid.abc123",
    "status": "sent",
    "recipient": "91XXXXXXXXXX"
  }
}

<?php
try {
    send_text('+91XXXXXXXXXX', 'Your order has shipped.', $apiKey);
} catch (LeadPatternException $e) {
    if ($e->status === 429) {
        sleep($e->retryAfter ?? 60); // wait, then retry once
        send_text('+91XXXXXXXXXX', 'Your order has shipped.', $apiKey);
    } elseif ($e->status === 403) {
        // 24-hour window closed (or IP / plan restriction) -> send a template instead
        send_template('+91XXXXXXXXXX', 'order_confirmation', 'en',
            [['name' => 'Customer'], ['order_id' => 'ORD-1234']], $apiKey);
    } else {
        throw $e;
    }
}

{
  "type": "error",
  "code": 403,
  "message": "Cannot send a free-form message. The 24-hour customer service window has expired. You may only send template messages after 24 hours of the last user message."
}