Web Services Example
Note: Creating web services requires an understanding of VTS's programming language, SOAP and XML coding. The following example is intended only to provide a general overview of how this system works, using simplified terms. It should not be used as a guide for creating your own VTS web service.
A relatively straight-forward example of a web service is to use a CGI application running on a remote website to read tag values from a VTS application.
In order to do this, we require at a minimum:
• A network connection.
• A running application that includes one or more tags with values to be read.
• A named realm that makes the application available.
• A WSDL file in the application directory that describes the service.
• A module in the application that provides the web service
• (Optional, but useful to ensure that the service is instantiated at startup:) A line in the application's AppMod.src module to name the service module above.
• A program running remotely to call and use the web service.
Assuming the first two items, the network connection and a working application are in place, the following steps will describe the process of setting up a web service to read values from the application from a PHP-enabled web page.
Our example application is named StationExample and is located in the directory C:\VTS\StationExample. It contains a single analog input named AI20_1.
Next step: Configure the realm
Web Service Example: Configuring a
Realm
Web Services Example: Creating a WSDL
file
Web Services Example: Creating the VTS
Module