I want to discuss about the type system in GFAC-Core.
Currently, GFAC module read and write a necessary information based on XML
schema (called GFAC-Schema) as a definition. GFAC-Schema library is
generated from XMLbeans (http://xmlbeans.apache.org/) and is referenced in
Examples of GFAC-Schema are:
HostTypeDescription, which describes an environment for a host such as Java
version, Temp directory, GridFTP endpoint etc.
ServiceTypeDescription, which describes a service such as parameters,
service name, etc.
GFAC-SimpleType, which defines a simple parameter type to the service such
as Boolean, Double, Integer, etc.
This is how system work roughly:
After deploying their software on a computing host, users will register
their host, application, service description via XBaya-GUI (Java Swing).
This registration information will be saved to XRegistry as XML string
according to XML schema.
When users invoke a (Web) service, GFAC will load the necessary information
(host, application directory, parameters, etc.) and execute the deployed
Then, GFAC parses the output from the software, wraps it and send out as an
appropriate parameter type format.
So, the question is do we want to continue using XML-Schema.
If, we agree to use XML-Schema, we should import some initial schema from
OGCE GFAC as a new module in Airavata. Also, we need to redesign some
For Instance, current HostType schema requires GridFTP Endpoint element
which is not necessary if a computing host doesn't have GridFTP.