On Wed, Jun 9, 2010 at 08:14, Daniel Kuc <[email protected]> wrote: > Is it possible to serialize an Edit object? I am trying to save all the > steps that I took to construct my workflow.
Hi! I'm afraid that's not yet possible.. We've had a plan to do so, as it could mean you could store the undo-history across Taverna runs, or indeed, as you say, get a full provenance of the workflow development. This would mean however that we would also have to make the user aware of this being stored, together with a clear-option, as users might not want to make public their previous mistakes while building the workflow! Technically it could be possible to store the edits, but at the moment most Edit instances are not proper Java Beans, meaning that they would be difficult to serialize and deserialize. They are also linking directly to the workflow objects they are affecting, when deserializing you would probably want the edit to relate to the newly made objects in workflow you just opened - so some kind of identification scheme for workflow components would be needed. (As previously discussed here under Semantification of Taverna). We also would like the Edit to have a more descriptive name or description that we could show in the Edit menu, so you could see 'Undo rename of processor' instead of just 'Undo'. This would require a fair bit of refactoring of all the possible Edits, which we have not scheduled time to do in the near future. We would of course welcome any help in doing so, a good opportunity is coming up after the 2.2 release, as we'll do some refactoring of 2.3 anyway when moving towards OSGI. We are developing a SCUFL2 workflow inspection and editing toolkit. [1] It might be a good idea for us to keep your question in mind, so that when we develop edits for SCUFL2 modifications, we can make these serializable, and hopefully so that they can be slightly meaningful in say an RDF export. Slightly side-tracked philosophical rant: It is our long-term plan to move the workbench to edit the abstract SCUFL2 model instead of the current mode, which is actually editing the live objects which (copy) will be used when executing the workflow. The original idea behind this mode was to facilitate live steering and modifications of a running workflow, but this has proven tricky as one needs to ensure the workflow is not running while applying the changes, etc. Taverna 2.2 will however include a Pause/Resume mechanism, bringing us one step closed to such a goal. The disadvantage of the current mode is that you need all the Taverna dependencies to edit a workflow, so with SCUFL2 we're moving to a more lightweight model descibing the workflow and the service bindings, which should be possible to generate or edit by say a web service or a Perl script. It could then be a future task for the translator that is mapping SCUFL2 to t2flow objects to facilitate modifications of a running workflow. Another way to do such modifications is to implement partial rerun, where you would run the new workflow, but using cached/previous values stored in provenance run where the service bindings and inputs are matching the previous run. This should be possible to implement with the current code, and would be useful also as a backup for services that might be down or which takes a long time to execute, simply to return the same value as last time. Anyway..back to the edits. The Next Generation Workbench [2] work, lead by Rishi Ramgolam and Jiten Bhagat of the myGrid team, will be using the SCUFL2 model for describing the workflow. I've copied this email to them so that they are aware of the ideas for serializing edits/actions. Taverna NG is built on various Eclipse framework which might make this easier to achieve. [1] http://www.mygrid.org.uk/dev/wiki/display/developer/SCUFL2 [2] http://www.mygrid.org.uk/dev/wiki/display/TNG -- Stian Soiland-Reyes, myGrid team School of Computer Science The University of Manchester ------------------------------------------------------------------------------ ThinkGeek and WIRED's GeekDad team up for the Ultimate GeekDad Father's Day Giveaway. ONE MASSIVE PRIZE to the lucky parental unit. See the prize list and enter to win: http://p.sf.net/sfu/thinkgeek-promo _______________________________________________ taverna-hackers mailing list [email protected] Web site: http://www.taverna.org.uk Mailing lists: http://www.taverna.org.uk/about/contact-us/ Developers Guide: http://www.taverna.org.uk/developers/
