- A method of making information available in a standardized way that could be accessed by any developer’s application over the Web.
- Is not an application
- Methods that can be called over the Internet and that can optionally return data to the calling code.
- Ideal for exchanging data between different systems.
- Based on solid, well understood standards
- Can make it easy to exchange data between different platforms
- Enables client-side pages to talk to web service on different domain
- Can be added to the application in two ways:
- Created and exposed to the Web, to share with other developers and other applications.
- Can be found on the Web and added to your own application.
4 Stage Process of a Web Service
- The client calls web service over a protocol.
- The client sends the method to the server, which contains instructions on what is needed from the web service.
- The server returns values and or an acknowledgement that it has received the method.
- The client gets the results and acts on the received information
Calling the Web Service
Request sent to the web service contains:-
- The web service’s URL
- The fact that it is an HTTP request
- The amount of information being sent
- The type of document you want back from the web server
- Information about the client
- The date of the request
- The parameters that you want to send to the web service.
Browser collects the information from the form and wraps it up in a document ready for transmission. This is called serialization.