Sort-override plugin

[future-figs]

Hi everyone!

I just wrote a plugin for manually changing artist-sort tags. It's similar to the existing rewrite, advancedrewrite, and substitute plugins, but it deliberately changes file metadata. This way, music players can read the file metadata and sort the files the same way beets does.

My central use-case is consolidating artists with "alter-egos" or "aliases" -- different stage names used on just one or two projects, for example MF DOOM's "Viktor Vaughn" and "King Geedorah" personas. I want these to be grouped in with the artist's main works, which means changing their albumartist_sort tags to "MF DOOM" match the mainline discography. It can also be used for one-off collaborations, e.g. sorting the one album by "The Velvet Underground & Nico" under "Velvet Underground, The" alongside their other records without Nico. (This is basically the same rationale as the existing plugins.)

All the "overrides" are set up in the config file. Under the albumartists: section, you can list any number of desired albumartist_sort values, and for each, any number of beets queries for albums onto which that tag will get stamped. That's sort_as: and aliases:, respectively. I'm pretty happy with this syntax; it's readable no matter how many "aliases" an artist goes by, you can use musicbrainz IDs instead of writing out artist/album names, and regex works.

The plugin triggers automatically at the end of the import process, when the sort tags get populated, and it can be re-run anytime with its own command. It's safe to run mbsync later, as it doesn't overwrite sort tags. If you really screw up the sort tags, you can disable the plugin and re-import problem albums (beet import -L $query) to get the default sort tags back from musicbrainz.

There are some potential areas for improvement:

• Option to toggle "auto" behavior during import
• Some way to restore the "original" sort tags
• Option to hook into beet write / beet move
• Handling of "plural" fields (e.g. albumartists_sort) -- currently these are totally ignored
• Option to toggle writing albumartist_sort to artist_sort as well -- this is a hack needed for my music player, which reads artist_sort even when sorting albums, not tracks
• Different handling of artist_sort vs 'albumartist_sort` -- I like albums, so this isn't my use-case and I have no idea how one might want tracks sorted by artist to look like

I attached the plugin file. Here's my config.yaml setup:

sortoverride:
  albumartists:
    - sort_as: "Aphex Twin"
      aliases:
        - albumartist:"AFX"
    - sort_as: "Gibbs, Freddie"
      aliases:
        - albumartist::"Freddie Gibbs.*"
    - sort_as: "InI"
      aliases:
        - album:"Center of Attention"
    - sort_as: "MF DOOM"
      aliases:
        - albumartist:"King Geedorah"
        - albumartist:"Madvillain"
        - albumartist:"Metal Fingers"
        - albumartist:"Viktor Vaughn"
        - albumartist::".*MF DOOM.*"
    - sort_as: "Velvet Underground, The"
      aliases:
        - album:"The Velvet Underground & Nico"
    - sort_as: "Ye"
      aliases:
        - albumartist:"KIDS SEE GHOSTS"

If it looks helpful, give it a shot and tell me what you think! I can try to put this into a PR if there's a desire.

sortoverride.py