Files residing in the Data One Core virtual file system (VFS) are processed by developing Data Shaper Graphs that contain a specialized Reader graph component and a Writer graph component, namely DataOneVFSReader and DataOneVFSWriter.
The main components in a Data Shaper graph are DataOneVFSReader and DataOneVFSWriter. Each graph must start with one or more DataOneVFSReader components and end with one or more DataOneVFSWriter components.
The main purpose of DataOneVFSReader is to stream the content of an input file residing on Data One VFS to the downstream Data Shaper graph, together with a set of file metadata, namely DataOneFileDescriptor (DOFD).
Conversely, the main purpose of DataOneVFSWriter is to store in an output file residing on Data One VFS, the content streamed by the upstream Data Shaper graph, together with a set of file metadata, namely DataOneFileDescriptor (DOFD).
The resulting graph performs the required processing on the file by combining DataOneVFSReader and DataOneVFSWriter with any other components available in the Data Shaper Designer palette. The graph itself is invoked from within a Mediation Contract using the specialized service task Data Shaper Processor, which submits the graphs and monitors their outcomes. Data Shaper graphs based on DataOneVFSReader and DataOneVFSWriter are not constrained to process a single input file and produce a single output file, both fan-out and fan-in data processing graphs can be easily implemented using the approach described above.
