I wondered if there was work ongoing on extending the types of variables that can be passed as workflow variables? The current selection of String, Integer and Double is pretty sparse.
Are there plans to add String types that can be entered via a file selector box (for file path definitions?) I think such things would really facilitate the usage of the GUI and allow better customization of a given workflow.
This is something that we are already at least in the planning stages on. For your specific request though, have a look at the file upload quickform node which does more or less exactly what you are looking for (I think). In fact, a lot of the quickforms are useful for making workflows easier to use if you plan on executing them more than once, specifically in combination with metanodes and especially if executed using our commercial Webportal.
for more information about QuickForms have a look at the QuickForms video tutorial at Youtube.
Regarding Peters first part of his question from 2013, is there any plans to support more types as flow variables? I some cases it’s necessary (and very time consuming) to convert data to String and parse it back. At least some basic serializable types shouldn’t be too hard to implement and would add a lot of value.