Over decades, SOAP web services have become the de facto standard for developing web services. Making a mind shift to adhere to REST architectural constraints is quite essential for the design of RESTful web APIs. Let's break down the design considerations of a RESTful web APIs, focusing on the core elements of the REST architecture style:
- Resources and their identifiers
- Interaction semantics for RESTful APIs (HTTP methods)
- Representation of resources
- Hypermedia controls
Let's start by discussing the guidelines for identifying resources in a problem domain.
Richardson Maturity Model—Leonardo Richardson has developed a model to help with assessing the compliance of a service to REST architecture style. The model defines four levels of maturity, starting from level-0 to level-3 as the highest maturity level. The maturity levels are decided considering the aforementioned principle elements of the REST architecture.