Making your first API

Making your first API

Audun Semb
Published 23.04.2017

Exposing an API to the world involves many factors, such as choice of technology, documentation and security, to mention a few. It can be difficult to implement the idea of a "API First". So what can you do? Think big, act small. The first API can be internal. Then you avoid many of the potential challenge that comes with exposing an API to the world.

The API and its place in the API economy is not an IT issue. It is nevertheless a fact that APIs are software interfaces. Let this be the basis for development of your first API.

Start by building a layer on top of an existing IT system. Let's say you have an old system that previously handled many different processes related to the company's core business. The system worked as a customer database, product database, CRM, and billing system. Several of the processes are - one after the other - completely, or partially, replaced by modern cloud-based systems. All of these systems then need customer data - and that (the same) data is stored in all the systems. It is perhaps more accurate to say that you wish the data was the same. It is not, because the data is maintained separately within each system. You can achieve coherence by building an API for customer data on the old system. APIs must offer retrieval, creation and maintenance of customer data. Then you have an architecture with a centralized customer database that is available for all your systems. You keep the old system, and its lifetime may be extended. At the same time the new architecture also allows you to more easily replace the customer database with a more modern solution when the timing is right.

The lessons learned from setting up and using internal API makes your organization more mature with regards to exposing its first API to the world. You have in other words taken the first step toward becoming a part of the API economy by making your first API