Support independent jobs across sessions

[chrisgorgo]

It's certain that we will see more and more datasets like MyConnectome and Midnight Scan Club. To efficiently process such dataset we need to support submitting independent jobs across sessions. In practice this would mean:

• addition of session analysis level and --session_label flag for selecting sessions (more details at https://groups.google.com/forum/#!topic/bids-apps-dev/Vnx5HHudqq4)
• addition of participant_anat analysis level to be run before any session levels

[effigies]

I think one of the relevant problems to consider here is separate working directories, which will attempt to re-run anatomical. I think we need to ensure that all necessary anatomical inputs to the BOLD workflow are in the anatomical derivatives, and use those, rather than reaching into the working directory.

I think at one point I had an open issue about a DataGrabber for fmriprep derivatives. That could be a useful component here.

[oesteban]

I think we need to ensure that all necessary anatomical inputs to the BOLD workflow are in the anatomical derivatives, and use those, rather than reaching into the working directory.

This is the key point here. +1

[poldrack]

just wanted to upvote this one again (just trying to analyze myconnectome data again).

[carolinarsm]

Also bumping this much needed feature, so +1.

[oesteban]

This will be possible when nipreps/smriprep#107 is merged in. Can't provide an ETA, but I'd like to see this fixed within 2 months.