home: services: xdg-base-directories: Deprecate XDG_LOG_HOME.

XDG_LOG_HOME is non-standard and log files should go to XDG_STATE_HOME
according to the XDG Base Directory Specification.

Fixes <https://issues.guix.gnu.org/61809>.

* gnu/home/services/desktop.scm (home-dbus-shepherd-services): Log to XDG_STATE_HOME.
* gnu/home/services/desktop.scm (home-unclutter-shepherd-services): Log to
XDG_STATE_HOME.
* gnu/home/services/mcron.scm (home-mcron-shepherd-services): Ditto.
* gnu/home/services/pm.scm (home-batsignal-shepherd-services): Ditto.
* gnu/home/services/shepherd.scm (launch-shepherd-gexp): Ditto.
* gnu/home/services/xdg.scm
(home-xdg-base-directories-configuration)[log-home]: Deprecate and unset default value.
(home-xdg-base-directories-environment-variables-service)
(ensure-xdg-base-dirs-on-activation): Handle field deprecation.
(home-xdg-base-directories-service-type): Update description.

Co-authored-by: Andrew Tropin <andrew@trop.in>
Signed-off-by: Andrew Tropin <andrew@trop.in>

5 files changed, 46 insertions, 27 deletions

diff --git a/gnu/home/services/desktop.scm b/gnu/home/services/desktop.scm
index 661fe7d283..626918fd9e 100644
--- a/gnu/home/services/desktop.scm
+++ b/gnu/home/services/desktop.scm
@@ -214,9 +214,9 @@ according to time of day.")))
                    (cons "DBUS_VERBOSE=1"
                          (default-environment-variables))
                    #:log-file
-                   (format #f "~a/dbus.log"
-                           (or (getenv "XDG_LOG_HOME")
-                               (format #f "~a/.local/var/log"
+                   (format #f "~a/log/dbus.log"
+                           (or (getenv "XDG_STATE_HOME")
+                               (format #f "~a/.local/state"
                                        (getenv "HOME"))))))
          (stop #~(make-kill-destructor)))))
 
@@ -264,10 +264,10 @@ according to time of day.")))
                (number->string
                 #$(home-unclutter-configuration-idle-timeout config)))
               #:log-file (string-append
-                          (or (getenv "XDG_LOG_HOME")
-                              (format #f "~a/.local/var/log"
+                          (or (getenv "XDG_STATE_HOME")
+                              (format #f "~a/.local/state"
                                       (getenv "HOME")))
-                          "/unclutter.log"))))))
+                          "/log/unclutter.log"))))))
 
 (define home-unclutter-service-type
   (service-type
diff --git a/gnu/home/services/mcron.scm b/gnu/home/services/mcron.scm
index 5f35bfe054..f51edd6634 100644
--- a/gnu/home/services/mcron.scm
+++ b/gnu/home/services/mcron.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
+;;; Copyright © 2021, 2023 Andrew Tropin <andrew@trop.in>
 ;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
 ;;; Copyright © 2022 Maxim Cournoyer <maxim.cournoyer@gmail.com>
 ;;;
@@ -99,10 +99,10 @@ Each message is also prefixed by a timestamp by GNU Shepherd."))
                                         #~())
                                  #$@files)
                            #:log-file (string-append
-                                       (or (getenv "XDG_LOG_HOME")
-                                           (format #f "~a/.local/var/log"
+                                       (or (getenv "XDG_STATE_HOME")
+                                           (format #f "~a/.local/state"
                                                    (getenv "HOME")))
-                                       "/mcron.log")))
+                                       "/log/mcron.log")))
                  (stop #~(make-kill-destructor))
                  (actions
                   (list (shepherd-schedule-action mcron files)))))))))
diff --git a/gnu/home/services/pm.scm b/gnu/home/services/pm.scm
index 5f09941827..d8361fd214 100644
--- a/gnu/home/services/pm.scm
+++ b/gnu/home/services/pm.scm
@@ -128,10 +128,10 @@
                                  (list "-i")
                                  (list)))
                      #:log-file (string-append
-                                 (or (getenv "XDG_LOG_HOME")
-                                     (format #f "~a/.local/var/log"
-                                               (getenv "HOME")))
-                                 "/batsignal.log")))
+                                 (or (getenv "XDG_STATE_HOME")
+                                     (format #f "~a/.local/state"
+                                             (getenv "HOME")))
+                                 "/log/batsignal.log")))
            (stop #~(make-kill-destructor))))))
 
 (define home-batsignal-service-type
diff --git a/gnu/home/services/shepherd.scm b/gnu/home/services/shepherd.scm
index ff6d629114..5585ef61b2 100644
--- a/gnu/home/services/shepherd.scm
+++ b/gnu/home/services/shepherd.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
+;;; Copyright © 2021, 2023 Andrew Tropin <andrew@trop.in>
 ;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
 ;;;
 ;;; This file is part of GNU Guix.
@@ -108,9 +108,10 @@ as shepherd package."
                       (or (getenv "XDG_RUNTIME_DIR")
                           (format #f "/run/user/~a" (getuid)))
                       "/shepherd/socket"))
-              (let ((log-dir (or (getenv "XDG_LOG_HOME")
-                                 (format #f "~a/.local/var/log"
-                                         (getenv "HOME")))))
+              (let* ((state-dir (or (getenv "XDG_STATE_HOME")
+                                    (format #f "~a/.local/state"
+                                            (getenv "HOME"))))
+                     (log-dir (string-append state-dir "/log")))
                 ;; TODO: Remove it, 0.9.2 creates it automatically?
                 ((@ (guix build utils) mkdir-p) log-dir)
                 (system*
diff --git a/gnu/home/services/xdg.scm b/gnu/home/services/xdg.scm
index ac557b4c3d..958772696b 100644
--- a/gnu/home/services/xdg.scm
+++ b/gnu/home/services/xdg.scm
@@ -1,6 +1,7 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2021, 2022 Andrew Tropin <andrew@trop.in>
 ;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
+;;; Copyright © 2023 Bruno Victal <mirai@makinata.eu>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -22,6 +23,7 @@
   #:use-module (gnu home services)
   #:use-module (gnu packages freedesktop)
   #:use-module (gnu home services utils)
+  #:use-module (guix deprecation)
   #:use-module (guix gexp)
   #:use-module (guix modules)
   #:use-module (guix records)
@@ -39,7 +41,7 @@
             home-xdg-base-directories-configuration-config-home
             home-xdg-base-directories-configuration-data-home
             home-xdg-base-directories-configuration-state-home
-            home-xdg-base-directories-configuration-log-home
+            home-xdg-base-directories-configuration-log-home  ; deprecated
             home-xdg-base-directories-configuration-runtime-dir
 
             home-xdg-user-directories-service-type
@@ -77,6 +79,7 @@
 
 (define (serialize-path field-name val) "")
 (define path? string?)
+(define-maybe path)
 
 (define-configuration home-xdg-base-directories-configuration
   (cache-home
@@ -97,12 +100,17 @@ read-only shared data, analogus to @file{/usr/share}, but for user.")
    (path "${XDG_RUNTIME_DIR:-/run/user/$UID}")
    "Base directory for programs to store user-specific runtime files,
 like sockets.")
+  ;; TODO: deprecated field, use $XDG_STATE_HOME(/log) instead.
   (log-home
-   (path "$HOME/.local/var/log")
+   maybe-path
    "Base directory for programs to store log files, analogus to
 @file{/var/log}, but for user.  It is not a part of XDG Base Directory
 Specification, but helps to make implementation of home services more
-consistent.")
+consistent."
+   (lambda (field-name val)
+     (when (maybe-value-set? val)
+       (warn-about-deprecation field-name #f #:replacement 'state-home))
+     (serialize-path field-name val)))
   (state-home
    (path "$HOME/.local/state")
    "Base directory for programs to store state data that should persist
@@ -117,7 +125,13 @@ portable enough to the user to warrant storing them in
             #f "XDG_~a"
             (object->snake-case-string (configuration-field-name field) 'upper))
            ((configuration-field-getter field) config)))
-   home-xdg-base-directories-configuration-fields))
+   ;; XXX: deprecated field, remove later
+   (if (maybe-value-set?
+        (home-xdg-base-directories-configuration-log-home config))
+       home-xdg-base-directories-configuration-fields
+       (filter-configuration-fields
+        home-xdg-base-directories-configuration-fields
+        '(log-home) #t))))
 
 (define (ensure-xdg-base-dirs-on-activation config)
   (with-imported-modules '((guix build utils))
@@ -138,7 +152,14 @@ portable enough to the user to warrant storing them in
                      ;; and will be provided by elogind or other service.
                      (and (not (string=? "XDG_RUNTIME_DIR" variable))
                           variable)))
-                 home-xdg-base-directories-configuration-fields)))))
+                 ;; XXX: deprecated field, remove later
+                 (if (maybe-value-set?
+                      (home-xdg-base-directories-configuration-log-home
+                       config))
+                     home-xdg-base-directories-configuration-fields
+                     (filter-configuration-fields
+                      home-xdg-base-directories-configuration-fields
+                      '(log-home) #t)))))))
 
 (define (last-extension-or-cfg config extensions)
   "Picks configuration value from last provided extension.  If there
@@ -157,10 +178,7 @@ are no extensions use configuration instead."
                 (default-value (home-xdg-base-directories-configuration))
                 (compose identity)
                 (extend last-extension-or-cfg)
-                (description "Configure XDG base directories.  This
-service introduces an additional @env{XDG_LOG_HOME} variable.  It's not
-a part of XDG specification, at least yet, but are convenient to have,
-it improves the consistency between different home services.  The
+                (description "Configure XDG base directories.  The
 services of this service-type is instantiated by default, to provide
 non-default value, extend the service-type (using @code{simple-service}
 for example).")))