home: services: Add home-beets-service-type.

* gnu/home/services/music.scm: New file.
* gnu/local.mk: Add this.
* doc/guix.texi: Document this.

Change-Id: Idc23a68276cb3fb07733bb38bc38b1c5a63c1d6a
Signed-off-by: Ludovic Courtès <ludo@gnu.org>

doc/guix.texi

@@ -129,6 +129,7 @@ Copyright @copyright{} 2024 Matthew Trzcinski@*
 Copyright @copyright{} 2024 Richard Sent@*
 Copyright @copyright{} 2024 Dariqq@*
 Copyright @copyright{} 2024 Denis 'GNUtoo' Carikli@*
+Copyright @copyright{} 2024 Fabio Natali@*
 
 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.3 or
@@ -47110,6 +47111,38 @@ documentation of the system service (@pxref{Networking Services,
 
 This section lists Home services that lack a better place.
 
+@subsubheading Beets Service
+
+@cindex Beets service, for Home
+The @code{(gnu home services music)} module provides the following
+service:
+
+@defvar home-beets-service-type
+@uref{https://beets.io, Beets} is a music file and metadata manager
+that can be used via its command-line interface, @command{beet}. Beets
+requires a YAML configuration file and this Guix Home service is to
+create such file.
+@end defvar
+
+The service can be used as follows:
+
+@lisp
+(service home-beets-service-type
+         (home-beets-configuration (directory "/home/alice/music")))
+@end lisp
+
+Additional options can be specified via the service wild-card field
+@code{extra-options}:
+
+@lisp
+(service home-beets-service-type
+         (home-beets-configuration
+          (directory "/home/alice/music")
+          (extra-options '("
+import:
+  move: yes"))))
+@end lisp
+
 @subsubheading Dictionary Service
 
 @cindex dictionary service, for Home

gnu/home/services/music.scm

@@ -0,0 +1,63 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2024 Fabio Natali <me@fabionatali.com>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu home services music)
+  #:use-module (guix gexp)
+  #:use-module (guix records)
+  #:use-module (gnu home services)
+  #:use-module (gnu packages music)
+  #:use-module (gnu packages video)
+  #:export (home-beets-configuration
+            home-beets-service-type))
+
+;;; Commentary:
+;;;
+;;; A Guix Home service to configure Beets, a music file and metadata manager.
+;;;
+;;; Code:
+
+(define-record-type* <home-beets-configuration>
+  home-beets-configuration make-home-beets-configuration
+  home-beets-configuration?
+  (package home-beets-package (default beets))
+  (directory home-beets-directory (default #f))
+  (extra-options home-beets-extra-options (default '()))
+  (extra-packages home-beets-extra-packages (default (list ffmpeg))))
+
+(define (home-beets-configuration->file config)
+  "Return the Beets configuration file corresponding to CONFIG."
+  (match-record config <home-beets-configuration>
+    (directory extra-options)
+    (plain-file "beets.yaml"
+                (string-append "directory: " directory "\n"
+                               (string-join extra-options "\n" 'suffix)))))
+
+(define home-beets-service-type
+  (service-type
+   (name 'home-beets)
+   (extensions
+    (list
+     (service-extension home-profile-service-type
+                        (lambda (config)
+                          (cons* (home-beets-package config)
+                                 (home-beets-extra-packages config))))
+     (service-extension home-xdg-configuration-files-service-type
+                        (lambda (config)
+                          (list `("beets/config.yaml"
+                                  ,(home-beets-configuration->file config)))))))
+   (description "Configure Beets, a music file and metadata manager.")))

gnu/local.mk

@@ -66,6 +66,7 @@
 # Copyright © 2023 Troy Figiel <troy@troyfigiel.com>
 # Copyright © 2024 David Elsing <david.elsing@posteo.net>
 # Copyright © 2024 Ashish SHUKLA <ashish.is@lostca.se>
+# Copyright © 2024 Fabio Natali <me@fabionatali.com>
 #
 # This file is part of GNU Guix.
 #
@@ -107,6 +108,7 @@ GNU_SYSTEM_MODULES =				\
   %D%/home/services/mail.scm			\
   %D%/home/services/media.scm			\
   %D%/home/services/messaging.scm		\
+  %D%/home/services/music.scm			\
   %D%/home/services/pm.scm			\
   %D%/home/services/shells.scm			\
   %D%/home/services/shepherd.scm		\