Reference

SDKs

Official client libraries. PHP shipping today; Node.js and Python on the roadmap.

The fastest path to a working integration is one of our official SDKs. They wrap the REST API with auto-refresh, idempotency, retry-with-backoff, typed exceptions, and a batteries-included webhook signature verifier — so you write business code, not boilerplate.

PHP

key2pay/key2pay-php

PHP 8.1+ · curl · openssl · MIT

bash

composer require key2pay/key2pay-php

php

<?php
require __DIR__ . '/vendor/autoload.php';

$client = new \Key2Pay\Client([
    'apiKey'      => getenv('KEY2PAY_API_KEY'),
    'secretKey'   => getenv('KEY2PAY_SECRET_KEY'),
    'environment' => 'sandbox',
]);

$tx = $client->payments->create([
    'amount'          => 50,
    'paymentMethodId' => '1008',     // SPEI MEX, from /payment-methods
    'country'         => 'MEX',
    'userEmail'       => 'cliente@ejemplo.com',
    'merchantOrderId' => 'ORD-12345',
]);

header('Location: ' . $tx['paymentFormUrl']);

Auto-refresh Bearer

Re-mints + retries 401 transparently

Idempotency built-in

UUID v4 per POST · BYO key supported

Typed exceptions

AuthenticationException, InvalidRequest, RateLimit, NotFound, …

Retry with backoff

Honours Retry-After · jittered exponential

Webhook signature verify

HMAC-SHA256 · 24h rotate-secret grace window

Sandbox-Simulate built-in

Pass `sandboxSimulate => 'paid'` for CI

Full reference + webhook handler example + rotation workflow in the package README. Source lives at sdks/php/ in the Key2Pay repo — publish to Packagist is in flight, install meanwhile via VCS:

bash

composer config repositories.key2pay vcs https://github.com/key2pay/key2pay-php
composer require key2pay/key2pay-php:dev-main

Other languages — generate from the OpenAPI spec

Until we ship Node.js and Python SDKs, scaffold a typed client straight from the OpenAPI spec:

bash

# Node / TS
npx oazapfts https://api.key2pays.com/api/openapi.json src/lib/key2pay-client.ts

# Python
openapi-python-client generate --url https://api.key2pays.com/api/openapi.json

# Go
oapi-codegen -package key2pay https://api.key2pays.com/api/openapi.json > key2pay.go

Auto-generated clients give you typed request/response shapes for free, but they don't include the helpers our PHP SDK ships (auto-refresh, webhook signature verifier, retry policy). You'll need to wrap those yourself — the per-language patterns are straightforward; see Webhooks & signing for the HMAC verification snippet.