Bagisto Payment Gateway Integration: A Practical Implementation Guide

The Modular Package Structure

Bagisto is built on Laravel, meaning any custom payment integration must be structured as an isolated package within the `packages/` directory. Direct modifications to the core `Webkul` namespace will instantly break your application upon upgrading to a new Bagisto release. Construct an agnostic Service Provider that registers your payment forms and webhook routes independently.

Configuring system.php & payment.php

Connecting your gateway to the Bagisto admin panel requires properly defining your `system.php` arrays. A single missing or undefined array key here will result in fatal admin errors (e.g. "Undefined array key 'info'"). All configurable fields—API Keys, Sandbox toggles, and Sort order—must map directly via your `payment.php` config file.

Holding Order State using Webhooks

A fatal mistake in custom integrations is processing inventory reductions immediately on checkout submission. We architect stateless IPN (Instant Payment Notification) listener routes. The order status must remain 'Pending' until the secure, cryptographically-signed webhook POST from the gateway confirms the funds are captured.

Common Mistakes

• Failing to Handle Float Precision: Floating point precision bugs when converting floats to integer strings (cents) for Stripe or SumUp APIs.
• Unsecured Webhooks: Processing successful order transitions without authenticating the incoming POST request's signature header against a secret hash.

Practical Checklist

• Step 1: Generate a modular Laravel package and register in `config/app.php`.
• Step 2: Implement the abstract `Payment` method class inherited from `Webkul\Payment\Payment`.
• Step 3: Build the Redirect URL controller logic and the corresponding IPN listener logic.
• Step 4: Mock webhook payloads in your local dev environment to forcibly test `payment_failed` database transitions.