Let’s see, What is SOAP Web Service? SOAP provides the envelope for sending Web Services messages over the Internet. It is part of the set of standards specified by the W3C.
Choose between SOAP Web Services and RESTful services
- If you require asynchronous processing
- In your service operations are stateful
- If you need formal contract/Interfaces
Choose RESTful Services:
- If you have limited bandwidth
- If your clients require caching.
- If your operations are stateless
Architecture of SOAP Web Service
Simple Object Access Protocol (SOAP) is a standard protocol specification for message exchange based on XML. Communication between the web service and client happens using XML messages.
A simple web service architecture has two components –
- Service provider
So as in above diagram, how a client will communicate to the service provider. So in order to communicate, client must know some information for e.g.
- Location of web services server
- Functions available, signature and return types of function.
- Communication protocol
- Input-output formats
The service provider will create a standard XML file which will have all above information.So If this file is given to client then the client will be able to access web service. This XML file is called WSDL.
What is WSDL?
One major component of a web service is Web Services Description Language (WSDL). It is an XML file that describes the web service technically in a machine readable format. That is, using this WSDL file we can understand things like,
- Port / Endpoint – URL of the web service (using which we should access it)
- Input message format
- Output message format
- Security protocol that needs to be followed (like https)
- Which protocol the web service uses
I just want this article to be a beginning point for your web service exploration. Do not stop with this, explore more and more and you will love this service-oriented architecture.