On Oct. 2, I attended the second Yireo Magento 2 Seminar in Utrecht, the Netherlands. There was a short talk on “APIs in Magento 2” presented by Andra Lungu, Magento developer at BitBull_IT.
We are currently building a very large Magento 2 store for one of our clients. For this project, we need to integrate with several external systems/platforms. For example: we need to regularly send order information to their CRM during order flow. To create a PDF of the order/invoice, we need the customer's relation number to print in the header of the document. Since the relationship number is not stored in Magento, we need to set up a REST API to retrieve this number from CRM.
I will give you a general overview on how to build your own web API with Magento 2 based on code examples.