Advanced Customization > Info*Engine User’s Guide > Info*Engine Data Management > Context Groups
  
Context Groups
When a task webject returns information from a data management system or from some other source, the information is returned as a group of objects and stored in the VDB. The VDB also contains special groups that store other information gathered during the request process. These groups are called “context” groups.
Context groups are maintained by Info*Engine and are made available to all webjects. Webjects can be authored to include the substitution syntax which substitutes values from the current context groups and modifies the behavior of the webject for this execution.
Three predefined groups are available within the collection of context groups: @SERVER, @FORM, and @COOKIE. A shorthand notation of SERVER, FORM, and COOKIE (excluding the @ symbol) can be used if no webject has created a group called SERVER, FORM, or COOKIE. The reserved names @SERVER, @FORM, and @COOKIE refer explicitly to the context groups and are the preferred names for the groups.
@SERVER
The @SERVER group contains attributes that are derived from the protocol used to communicate from the web browser to the web server. It can contain attributes such as Accept-Language or Auth-User. Refer to the current web-browser-to-web-server protocol specification to find more information on the individual attributes found in this group. To determine the exact contents of the current @SERVER group, you can execute the Echo-Request display webject.
@FORM
The @FORM group contains attributes that are obtained from the CGI query specification data that is received with the URL used to access the JSP page. It also contains any HTML form data that was received as the result of a web browser POST request.
@COOKIE
The @COOKIE group contains one element that has an attribute for each cookie that is processed during the connection to the JSP page. The attribute name is the name of the cookie and the value is the value of the cookie.
In addition to these groups, the Auth-Map context group is created when an authentication task executes. For more information, see Credentials Mapping.