Taking a closer look at whats in

solidus_gateway

and I don’t see a payment method for Checkout.com so you may have to write your own, but that extension contains a number of implementations which may help you get started. The Solidus guides on the payment system may be a good starting point as well to help you get a better sense of how Solidus integrates with payment providers - https://guides.solidus.io/developers/payments/overview.html

As far as your original question, the documentation you linked seems to be specifically for contributing to

active_merchant

so it is more meant to help developers add new gateways to that library. It could be helpful in terms of understanding the API active merchant implements for each of the gateways but since there seems to be already an implementation of the gateway you want in that library I think your task would be to write the Solidus wrapper around the active merchant implementation found here (https://github.com/activemerchant/active_merchant/blob/master/lib/active_merchant/billing/gateways/checkout.rb) so you can use that as a payment method in Solidus.

I would start by looking at some of the other gateways implemented in

solidus_gateway

and hopefully that gives you a better idea of what you need to do.

Checkout.com is already integrated and we have a working payment system with that. Now, I want to implement AreebaApi payment gateway for a different environment but I couldn’t find any library support for this gateway. So, I though about implementing the gateway for AreebaAPI using active_merchant guides.

Here is the link for the payment gateway integration guide. https://epayment.areeba.com/api/documentation/integrationGuidelines/hostedSession/integrationModelHostedSession.html

Please share your thought on this. Should I use the active_merchant contribution guides or is there any better way to implement a gateway in solidus?

@Chris Todorov Please advice.

You don’t need to implement the Active Merchant API you linked for your payment method to work with Solidus as that still needs to be wrapped in a Solidus implementation. You can save yourself some work by just implementing the Solidus APIs if you only need to use this with this platform.