REST or SOAP

By annak

- 3 minutes read - 509 words

First of all, let us consider whether we can compare those web services. SOAP (Simple Object Access Protocol), as the full name suggests, is a protocol. On the other hand, REST is an architectural style. It allows more flexibility and is considered easier to implement. RESTful applications have become ubiquitous in recent years, with SOAP web services lagging behind. There is no simple answer to whether one is ‘better’ than the other - it depends on the use case.

About SOAP

Some use cases where SOAP would be a preferred choice include large-scale enterprise projects where reliability and formal contract are of paramount importance and for ACID-compliant transactions. As SOAP works in synchronously, it is a better choice for scenarios where the client needs to know the status of the web service in a very short time.

Web protocols

By implementing SOAP, it is possible to use a different protocol for messaging than HTTP, including:

  • SMTP,
  • TCP,
  • JMS protocols.

Web Service Description Language

A SOAP web service includes a WSDL (Web Service Description Language), an XML-based document defining the way a web service is consumed. WSDL is either generated automatically or coded manually. In either case, it ensures the clarity and predictability of the service.

About REST

REST stands for REpresantational State Transfer. Web services conforming to the REST style are known as RESTful. These APIs are stateless so each request is independent of another. This feature makes REST scalable and easy to cache. Other characteristics required for an API to be considered RESTful:

  • uniform interface,
  • client-server decoupling,
  • layered system architecture.

The rise of RESTful APIs is tied to cloud computing and microservices. REST is faster and considered more efficient than SOAP, multiple response formats are also possible — JSON, HTML, XML, plain text. This has also contributed to the popularity of REST in recent years.

Security concerns

As SOAP is much stricter, it is a preferable choice for applications where security is crucial. This would be a preferred choice when web services concerning regulated industries are considered.

Implementation

Both SOAP and REST are language-agnostic (language independent) allowing engineers to connect to a web service developed in a different language. However, the implementation in some cases might be cumbersome, and if there are no clear advantages of one over the other, it is also worthwhile to consider what the available resources are.

SOAP, in spite of trying to pass for a ‘simple’ service, might not be so simple after all, especially when implementing it with JavaScript. Using Java with REST was until recently unwieldy. Java 11 offers fully asynchronous HTTP/1.1 implementation.

Summary

To sum up, there is no clear winner and the best choice depends on the scenario. As REST has become the most popular choice in the recent years, it is important to consider other factors such as:

  • security,
  • which programming language is going to be used,
  • shoudl the service work synchronously or asynchronously?

References