SOAP vs. REST: A Look at Two Different API Styles
When talking about API (application programming interface) architectures, it’s common to compare SOAP vs. REST, two of the most common API paradigms. Although the two are often compared as apples to apples, they’re inherently different technologies and aren’t easily compared on a granular level.
What is an API?
In the simplest of terms, an API is a piece of software that plugs one application directly into the data and services of another by granting it access to specific parts of a server. APIs let two pieces of software communicate, and they’re the basis for most modern applications. They allow us to streamline IT architectures, automate marketing workflows, and make it easier to share data sets.
What is a rest API?
REST (Representational State Transfer) is truly a “web services” API. REST APIs are based on URIs (Uniform Resource Identifier, of which a URL is a specific type) and the HTTP protocol and use JSON for a data format, which is super browser-compatible. (It could also theoretically use the SOAP protocol, as we mentioned above.) REST APIs can be simple to build and scale, but they can also be massive and complicated—it’s all in how they’re built, added on to, and what they’re designed to do.
What is SOAP?
SOAP (Simple Object Access Protocol) is its own protocol and is a bit more complex by defining more standards than REST—things like security and how messages are sent. These built-in standards do carry a bit more overhead. Still, they can be a deciding factor for organizations that require more comprehensive features in the way of security, transactions, and ACID (Atomicity, Consistency, Isolation, Durability) compliance. For the sake of this comparison, we should point out that many of the reasons why SOAP is a good choice rarely apply to web services scenarios, which makes it more ideal for enterprise-type situations.