Creating a simple SOAP client
Using SOAP, in contrast to the process of implementing a REST client or server, is quite easy as there is a PHP SOAP extension that provides both capabilities.
Note
A frequently asked question is "what is the difference between SOAP and REST?" SOAP uses XML internally as its data format. SOAP uses HTTP but only for transport, and otherwise has no awareness of other HTTP methods. REST directly operates HTTP, and can use anything for data formats, but JSON is preferred. Another key difference is that SOAP can operate in conjunction with a WSDL, which makes the service self-describing, thus more publicly available. Thus, SOAP services are often offered by public institutions such as national health organizations.
How to do it...
For this example, we will make a SOAP request for an existing SOAP service offered by the United States National Weather service:
The first consideration is to identify the WSDL document. The WSDL is an XML document that describes the service...
