Debug information from LAS and the backend services
Backend services (particularly the Ferret backend) write debug information which can be displayed on the output page.
The processes that create the output product can optionally writedebug information to a file, the contents of which can be displayed onthe output page for that product. Most output templates provided with LAS use an IFRAME to display this information, however it is onlydisplayed when the debug query parameter or propery is set to debug or true. Youmust take one of the actions below to set the appropriate debug parameterto see this debug information on the output page. This debug outputstream is very helpful in the case of the Ferret backend service sinceit contains a record of each Ferret statement that is executed and thevalues of all of the Ferret symbols. N.B. When a request is submitted with debug=true, caching is turned off.
Getting debug output using a query parameter.
Submitting a request to the LAS Product Server with a query parameter of debug=true will make LAS return debug information from the request in the output of the request.
Getting debug output using a property in the LAS configuration
You can also set a property in the LAS configuration to make LAS return the same debug information. Inserting the following will cause at debug information to be displayed for what ever data sets and/or variables to which theproperty has been applied. (Data sets inherit properties set outsidethe <datasets> element, variables inherit properties from theirparent data set).
Getting debug output using a property in the UI Request
If you are a client writer you can also modify the request XML to include the same debug property in the request (instead of adding to the configuration) which will also cause the debug machinery to produce the debug output.