Processors

A processor is a data production unit. A regular processor invokes a service through a known interface. Defined processor types are webservice, diet and beanshell. Special processors are workflow source (a processor with no inbound connectivity, delivering a list of externally defined data values), sink (a processor with no outbound connectivity, receiving some workflow output) and constant (a processor delivering a single, constant value). To improve readability, the source, sink and constant processors are grouped in an <interface> tag within the document. Other examples of processors are grouped in a <processors> tag. Web services define a <wsdl> tag pointing to their WSDL description and the operation to invoke. Beanshells define a <script> tag containing the java code to interpret. DIET services define a <diet> tag describing the path to service to invoke. (When executing the workflow using the DIET workflow engine, only processors containing a <diet> tag can be used.) The <diet> tag contains the path attribute that matches exactly the DIET service name, and optionnally contains the 'estimation' attribute (with value keyword 'constant') whenever the computation time estimation for this service does not depend on input data (using this option may reduce considerably the load on the DIET platform because the request for performance estimation is done only once by the MA instead of being done for each task).