Add "Lightweight Music Server" application + service

[arthurl]

Motivation for this change

It's a nice efficient music streaming server, especially suitable for resource constrained devices / servers. See https://github.com/epoupon/lms.

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
  • armv7l-linux
• For non-Linux: Is sandbox = true set in nix.conf? (See Nix manual)
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 21.11 Release Notes (or backporting 21.05 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
  • (Release notes changes) Ran nixos/doc/manual/md-to-db.sh to update generated release notes
• Fits CONTRIBUTING.md.

[arthurl]

Note: "Checking EditorConfig / tests" fails with "Wrong indent style found (tabs instead of spaces)" because tabs are in the patch included.

[aanderse]

Thanks for your contribution. I have left a few suggestions for the NixOS module that I hope you find helpful. Please don't hesitate to reach out for any reason.

[arthurl]

hi @aanderse, thanks for the reviewing, all very good suggestions.

Where can I read up about library functions such as mkMerge? The nix language reference only covers the language itself, not the library functions…

[arthurl]

Note: there is one strange issue. The service configuration throws a strange error if I use the INI format instead of toml here (i.e. settingsFormat = pkgs.formats.ini {};, with:

(Please ignore the line numbers, as they might have changed due to whitespace added.)

error: while evaluating the attribute 'config.system.build.toplevel' at /etc/nixpkgs/nixos/modules/system/activation/top-level.nix:293:5:
while evaluating 'foldr' at /etc/nixpkgs/lib/lists.nix:52:20, called from /etc/nixpkgs/nixos/modules/system/activation/top-level.nix:128:12:
while evaluating 'fold'' at /etc/nixpkgs/lib/lists.nix:55:15, called from /etc/nixpkgs/lib/lists.nix:59:8:
while evaluating 'showWarnings' at /etc/nixpkgs/lib/trivial.nix:311:28, called from /etc/nixpkgs/nixos/modules/system/activation/top-level.nix:125:10:
while evaluating 'foldr' at /etc/nixpkgs/lib/lists.nix:52:20, called from /etc/nixpkgs/lib/trivial.nix:311:33:
while evaluating 'fold'' at /etc/nixpkgs/lib/lists.nix:55:15, called from /etc/nixpkgs/lib/lists.nix:59:8:
while evaluating the attribute 'warnings' at undefined position:
while evaluating 'g' at /etc/nixpkgs/lib/attrsets.nix:298:19, called from undefined position:
while evaluating anonymous function at /etc/nixpkgs/lib/modules.nix:140:72, called from /etc/nixpkgs/lib/attrsets.nix:301:20:
while evaluating the attribute 'value' at /etc/nixpkgs/lib/modules.nix:525:9:
while evaluating the option `warnings':
while evaluating the attribute 'mergedValue' at /etc/nixpkgs/lib/modules.nix:557:5:
while evaluating the attribute 'values' at /etc/nixpkgs/lib/modules.nix:551:9:
while evaluating the attribute 'values' at /etc/nixpkgs/lib/modules.nix:650:7:
while evaluating anonymous function at /etc/nixpkgs/lib/modules.nix:537:28, called from /etc/nixpkgs/lib/modules.nix:537:17:
while evaluating definitions from `/etc/nixpkgs/nixos/modules/system/boot/systemd.nix':
while evaluating 'dischargeProperties' at /etc/nixpkgs/lib/modules.nix:609:25, called from /etc/nixpkgs/lib/modules.nix:538:137:
while evaluating the attribute 'value' at /etc/nixpkgs/lib/modules.nix:392:44:
while evaluating anonymous function at /etc/nixpkgs/lib/attrsets.nix:256:10, called from undefined position:
while evaluating anonymous function at /etc/nixpkgs/nixos/modules/system/boot/systemd.nix:905:16, called from /etc/nixpkgs/lib/attrsets.nix:256:16:
while evaluating 'optional' at /etc/nixpkgs/lib/lists.nix:254:20, called from /etc/nixpkgs/nixos/modules/system/boot/systemd.nix:912:16:
while evaluating the attribute 'serviceConfig.Type' at undefined position:
while evaluating 'g' at /etc/nixpkgs/lib/attrsets.nix:298:19, called from undefined position:
while evaluating anonymous function at /etc/nixpkgs/lib/modules.nix:140:72, called from /etc/nixpkgs/lib/attrsets.nix:301:20:
while evaluating the attribute 'value' at /etc/nixpkgs/lib/modules.nix:525:9:
while evaluating the option `systemd.services.lms.serviceConfig':
while evaluating the attribute 'mergedValue' at /etc/nixpkgs/lib/modules.nix:557:5:
while evaluating 'merge' at /etc/nixpkgs/lib/types.nix:386:20, called from /etc/nixpkgs/lib/modules.nix:559:59:
while evaluating 'filterAttrs' at /etc/nixpkgs/lib/attrsets.nix:124:23, called from /etc/nixpkgs/lib/types.nix:387:35:
while evaluating anonymous function at /etc/nixpkgs/lib/attrsets.nix:125:29, called from /etc/nixpkgs/lib/attrsets.nix:125:18:
while evaluating anonymous function at /etc/nixpkgs/lib/types.nix:387:51, called from /etc/nixpkgs/lib/attrsets.nix:125:62:
while evaluating the attribute 'ExecStart' at /etc/nixpkgs/lib/attrsets.nix:366:7:
while evaluating anonymous function at /etc/nixpkgs/lib/types.nix:387:86, called from /etc/nixpkgs/lib/attrsets.nix:366:15:
while evaluating the attribute 'optionalValue' at /etc/nixpkgs/lib/modules.nix:569:5:
while evaluating the attribute 'values' at /etc/nixpkgs/lib/modules.nix:551:9:
while evaluating the attribute 'values' at /etc/nixpkgs/lib/modules.nix:650:7:
while evaluating anonymous function at /etc/nixpkgs/lib/modules.nix:537:28, called from /etc/nixpkgs/lib/modules.nix:537:17:
while evaluating definitions from `/etc/nixpkgs/nixos/modules/services/misc/lms.nix':
while evaluating 'dischargeProperties' at /etc/nixpkgs/lib/modules.nix:609:25, called from /etc/nixpkgs/lib/modules.nix:538:137:
while evaluating the attribute 'value' at /etc/nixpkgs/lib/types.nix:391:60:
while evaluating the attribute 'text' of the derivation 'lms.conf' at /etc/nixpkgs/pkgs/stdenv/generic/make-derivation.nix:201:11:
while evaluating 'toINI' at /etc/nixpkgs/lib/generators.nix:118:6, called from /etc/nixpkgs/pkgs/pkgs-lib/formats.nix:104:31:
while evaluating 'mapAttrsToStringsSep' at /etc/nixpkgs/lib/generators.nix:121:44, called from /etc/nixpkgs/lib/generators.nix:129:7:
while evaluating anonymous function at /etc/nixpkgs/lib/attrsets.nix:256:10, called from undefined position:
while evaluating 'mkSection' at /etc/nixpkgs/lib/generators.nix:124:31, called from /etc/nixpkgs/lib/attrsets.nix:256:16:
while evaluating anonymous function at /etc/nixpkgs/lib/generators.nix:88:6, called from /etc/nixpkgs/lib/generators.nix:126:14:
while evaluating 'mapAttrsToList' at /etc/nixpkgs/lib/attrsets.nix:255:23, called from /etc/nixpkgs/lib/generators.nix:88:52:
value is a boolean while a set was expected, at /etc/nixpkgs/lib/attrsets.nix:256:39

[arthurl]

I can't figure out why... but toml works, so the PR is fine as is.

[aanderse]

It might be worth closing this PR and creating a new one so we don't spam all the people who accidentally were subscribed to this.