How to pass parameters to Rappture tools

This document describes how Rappture will handle tool parameters that might be passed in from the HUBzero middleware. Rappture detects this upon startup, when the $TOOL_PARAMETERS environment variable is set. Right now, Rappture interprets only "file" parameters. The name associated with a file parameter determines how Rappture will treat the file:

file(load):/path/to/run.xml

Load the given file into the runtime environment. There can be one or more, to load one or more results. This is equivalent to the command line invocation rappture -load /path/to/run.xml.

file(execute):/path/to/driver.xml

Execute the given driver file without the interactive GUI. Store status information (progress during the run) in the file rappture.status. This is equivalent to the command line invocation rappture -execute /path/to/driver.xml.

file(input):/path/to/driver.xml

Load the given driver file into the runtime environment as the initial set of input values. This is similar to file(load), but ignores anything in the output section and instead looks only for input values.

file(into:input.string(indeck)):/path/to/textfile

Load the contents of the given file into the Rappture element identified by the text following into:. In this example, the text within /path/to/textfile is loaded into a Rappture string control at input.string(indeck).

Bigger step: Extend the parameter passing syntax to include "string" parameters.

This will let you inline the values in the URL. Example: {{{ string(input.number(temperature).default):300K string(input.choice(model).default):boltzman }}} The real advantage of the inline string is you can then override any tag in Rappture. {{{ number(input.number(temperature).min):3K number(input.number(temperature).max):10000K }}}

We may yet reach the point of adding things like number and string as parameters, but this would push lots of Rappture-specific info into the middleware system, which validates all of these parameters as they pass in through the URL. Instead, we'll stick with using driver files for now as a means of passing input values. Note that a driver doesn't have to be a complete set of inputs. You can specify a driver with a single parameter and current value, as you might for the loader.