The Simple Object Access Protocol (SOAP) has been around for more than a decade. While HTTP-based API's and RESTful services are the current trend, SOAP web services are still the rock bed of most businesses and contemporary systems.
On-premises API gateways such as the CA API Gateway has had support for publishing SOAP web services for quite a while.
In fact, there is still such demand in the industry for integration with SOAP services that Microsoft's newer cloud-based Azure API Management service also now has the capability to publish SOAP API's.
The .NET library Nancy is an excellent lightweight web framework for building HTTP-based web services. While Nancy will not itself ship support for SOAP it still can be used for hosting SOAP web services, if you can create the SOAP payload.
Libraries such as Nancy or Mock4Net (a tiny mock HTTP server for .NET) can be used in automated Unit Tests to dynamically create mock web services that return the exact response required for each specific test case. In fact, I personally use this specific technique to perform advanced Unit Testing of black-box code artefacts such as BizTalk orchestrations.
However, creating and composing a SOAP envelope, header, and body or fault has always been a tricky undertaking, and unless you have studied the SOAP specifications in detail and use them daily, it is easy to either forget or confuse the differences between SOAP 1.1 and SOAP 1.2 - that is, until now!
Introducing the ChannelAdam SOAP Library – a fluent .NET API to make it as easy as possible to create a SOAP 1.1 or SOAP 1.2 payload.
For information on how to get started, please see the usage documentation.
You might also be interested in the ChannelAdam Nancy SOAP Library which makes using SOAP with Nancy even easier.