git-annex now has support for storing [[arbitrary metadata|metadata]] about annexed files. For example, this can be used to tag files, to record the author of a file, etc. The metadata is synced around between repositories with the other information git-annex keeps track of. One nice way to use the metadata is through **views**. You can ask git-annex to create a view of files in the currently checked out branch that have certian metadata. Once you're in a view, you can move and copy files to adjust their metadata further. Rather than the traditional hierarchical directory structure, views are dynamic; you can easily refine or reorder a view. Let's get started by setting some tags on files. No views yet, just some metadata: [[!template id=note text=""" To avoid needing to manually tag files with the year (and month), run `annex.genmetadata true`, and git-annex will do it for you when adding files. """]] # git annex metadata --tag todo work/2014/* # git annex metadata --untag todo work/2014/done/* # git annex metadata --tag urgent work/2014/presentation_for_tomorrow.odt # git annex metadata --tag done work/2013/* work/2014/done/* # git annex metadata --tag work work # git annex metadata --tag video videos # git annex metadata --tag work videos/operating_heavy_machinery.mov # git annex metadata --tag done videos/old # git annex metadata --tag new videos/lotsofcats.ogv # git annex metadata --tag sound podcasts # git annex metadata --tag done podcasts/*/old # git annex metadata --tag new podcasts/*/recent So, you had a bunch of different kinds of files sorted into a directory structure. But that didn't really reflect how you approach the files. Adding some tags lets you categorize the files in different ways. Ok, metadata is in place, but how to use it? Time to change views! # git annex view tag=* view (searching...) Switched to branch 'views/_' ok [[!template id=note text=""" Notice that a single file may appear in multiple directories depending on its tags. For example, `lotsofcats.ogv` is in both `new/` and `video/`. """]] This searched for all files with any tag, and created a new git branch that sorts the files according to their tags. # tree -d work todo urgent done new video sound Ah, but you're at work now, and don't want to be distracted by cat videos. Time to filter the view: # git annex vfilter tag=work vfilter Switched to branch 'views/(work)/_' ok Now only the work files are in the view, and they're otherwise categorized according to their other tags. So you can check the `urgent/` directory to see what's next, and look in `todo/` for other work related files. Now that you're in a tag based view, you can move files around between the directories, and when you commit your changes to git, their tags will be updated. # git mv urgent/presentation_for_tomorrow_{work;2014}.odt ../done # git commit -m "a good day's work" metadata tag-=urgent metadata tag+=done You can return to a previous view by running `git annex vpop`. If you pop all the way out of all views, you'll be back on the regular git branch you originally started from. You can also use `git checkout` to switch between views and other branches. ## fields Beyond simple tags and directories, you can add whatever kinds of metadata you like, and use that metadata in more elaborate views. For example, let's add a year field. # git checkout master # git annex metadata --set year=2014 work/2014 # git annex metadata --set year=2013 work/2013 # git annex view year=* tag=* Now you're in a view with two levels of directories, first by year and then by tag. # tree -d 2014 |-- work |-- todo |-- urgent `-- done 2013 |-- work `-- done Oh, did you want it the other way around? Easy! # git annex vcycle # tree -d work |-- 2014 `-- 2013 todo `-- 2014 urgent `-- 2014 done |-- 2014 `-- 2013 ## location fields Let's switch to a view containing only new podcasts. And since the podcasts are organized into one subdirectory per show, let's include those subdirectories in the view. # git checkout master # git annex view tag=new podcasts/=* # tree -d This_Developers_Life Escape_Pod GitMinutes The_Haskell_Cast StarShipSofa That's an example of using part of the directory layout of the original branch to inform the view. Every file gets fields automatically set up corresponding to the directory it's in. So a file"foo/bar/baz/file" has fields "/=foo", "foo/=bar", and "foo/bar/=baz". These location fields can be used the same as other metadata to construct the view. This has probably only scratched the surface of what you can do with views.