What is a temporary directory and what is it used for

Visual LANSA Framework

What is a temporary directory and what is it used for?

The temporary directory, which is defined via the Administrator's console, is used to store temporary state information for active Web browser Visual LANSA Framework applications.

It is also used to dynamically create XML data islands that are inserted into web pages being back sent to client browser applications.

With regard to the location of the temporary directory:   

  • The temporary directory used can be anywhere in a network, but it is best physically located on the LANSA application server for performance reasons.
  • The LANSA application server uses the real temporary directory name when it is creating the state management and XML data island files. It needs this name to be correctly specified (from it's point of view) so that it can write to files in this directory.
  • The LANSA application server never directly uses the virtual temporary directory name. However, it needs to know what it's name is (from the HTTP server's point of view) so that it can generate HTML pages containing correctly formatted <!--#include virtual="xxxxxxxxxxxxxx" --> directives for the HTTP server.  These are used to dynamically insert the XML data islands into web pages being sent back to client browsers.   
  • The HTTP server needs to be able to locate the temporary directory by using the virtual name specified in the <!--#include virtual="xxxxxxxxxxx" --> directives. This allows it to read the specified file and include it into the HTML page that is sent out to the client's browser. This is why SSI (server side includes) need to be enabled in your chosen HTTP server.