[bug#69781] [PATCH] services: Add the Guix Home Service

[bug#69781] [PATCH] services: Add the Guix Home Service

[Richard Sent]

This patch adds a Guix Home Service, which allows for configuring/deploying an
operating-system declaration with an associated home-environment.

* gnu/services/guix.scm: Add guix-home-service and guix-home-shepherd-service
* gnu/home/services/shepherd.scm: Don't attempt to launch user shepherd when
the system shepherd runs guix-home-<user>
* doc/guix.texi: Add documentation for guix-home-service

Change-Id: Ifbcc0878d934aa4abe34bb2123b5081fb432aa8e
---

Hi Guix. This patch adds support for activating a home configuration
as part of a Guix System configuration. It does this by creating a
one-shot shepherd service that runs the home environment activation
script.

This patch is based on code from Andrew Tropin [1], used with permission.
[2]. Given that fact I'm not 100% sure I handled the copyright headers
correctly; let me know if they need changed.

There was an issue where the activation script would attempt to also
launch the user-level shepherd, which would fail as /run/user/<uid>
would not usually exist. It was a benign issue (symlinks would still
be set up), but I decided an environment variable would be the best
way to avoid printing spurious warnings to the shepherd log file.

I also changed the rde code from relying on term-tty1 to
user-processes. I've not observed any failed activations with this
change and it also allows the operating-system to run in a container,
unlike term-tty1.

[1] https://git.sr.ht/~abcdw/rde/tree/master/item/src/gnu/services/home.scm
[2] https://lists.sr.ht/~abcdw/rde-discuss/%3C87h6j0rqmi.fsf%40freakingpenguin.com%3E

 doc/guix.texi                  | 32 ++++++++++++++++++++++++++++
 gnu/home/services/shepherd.scm |  7 +++++-
 gnu/services/guix.scm          | 39 ++++++++++++++++++++++++++++++++++
 3 files changed, 77 insertions(+), 1 deletion(-)

diff --git a/doc/guix.texi b/doc/guix.texi
index 858d5751bf..5523d1a174 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -125,6 +125,7 @@
 Copyright @copyright{} 2023 Graham James Addis@*
 Copyright @copyright{} 2023 Tomas Volf@*
 Copyright @copyright{} 2024 Herman Rimm@*
+Copyright @copyright{} 2024 Richard Sent@*
 
 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.3 or
@@ -39567,6 +39568,37 @@ Guix Services
 @end table
 @end deftp
 
+@subsubheading Guix Home Service
+The Guix Home Service allows for associating Guix @ref{Declaring the
+Home Environment, home-environment} declarations with a Guix
+@ref{operating-system Reference, operating-system}.
+
+@defvar guix-home-service-type
+Service type for the Guix Home Service.  Its value must be an
+association list. The key of each pair is a string representing the user
+to deploy the configuration under and the value is a home-environment
+configuration.
+
+@lisp
+(define my-home
+  (home-environment
+   ...))
+
+(operating-system
+  (services (list
+             (service guix-home-service-type
+                      `(("alice" ,my-home))))))
+@end lisp
+
+This service can be extended by other services to add additional home
+environments, as in this example:
+
+@lisp
+(simple-service 'my-extra-home home-service-type
+                `(("bob" ,my-extra-home))))
+@end lisp
+@end defvar
+
 @subsubheading Nar Herder
 The @uref{https://git.cbaines.net/guix/nar-herder/about/,Nar Herder} is
 a utility for managing a collection of nars.
diff --git a/gnu/home/services/shepherd.scm b/gnu/home/services/shepherd.scm
index 176f4575cb..e68dea6954 100644
--- a/gnu/home/services/shepherd.scm
+++ b/gnu/home/services/shepherd.scm
@@ -132,7 +132,12 @@ (define (ensure-shepherd-gexp config)
               (format #f "/run/user/~a" (getuid)))
           "/shepherd/socket"))
         #$(reload-configuration-gexp config)
-        #$(launch-shepherd-gexp config)))
+        ;; Don't attempt to start user shepherd if the system is running the
+        ;; activation script. /run/user/<uid> may not have been created
+        ;; yet. But do otherwise so if the runtime dir does not exist an error
+        ;; is logged.
+        (unless (getenv "GUIX_SYSTEM_IS_RUNNING_HOME_ACTIVATE")
+          #$(launch-shepherd-gexp config))))
 
 (define (shepherd-xdg-configuration-files config)
   `(("shepherd/init.scm" ,(home-shepherd-configuration-file config))))
diff --git a/gnu/services/guix.scm b/gnu/services/guix.scm
index c438da531c..5f649cbb6f 100644
--- a/gnu/services/guix.scm
+++ b/gnu/services/guix.scm
@@ -1,5 +1,6 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2019, 2020, 2021, 2022 Christopher Baines <mail@cbaines.net>
+;;; Copyright © 2024 Andrew Tropin <andrew@trop.in>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -101,6 +102,8 @@ (define-module (gnu services guix)
 
             guix-data-service-type
 
+            guix-home-service-type
+
             nar-herder-service-type
             nar-herder-configuration
             nar-herder-configuration?
@@ -686,6 +689,42 @@ (define guix-data-service-type
    (description
     "Run an instance of the Guix Data Service.")))
 
+\f
+;;;
+;;; Guix Home Service
+;;;
+
+(define (guix-home-shepherd-service config)
+  (map (lambda (x)
+         (let ((user (car x))
+               (he (cdr x)))
+           (shepherd-service
+            (documentation "Activate Guix Home.")
+            (requirement '(user-processes))
+            (provision (list (symbol-append 'guix-home- (string->symbol user))))
+            (one-shot? #t)
+            (auto-start? #t)
+            (start #~(make-forkexec-constructor
+                      '(#$(file-append he "/activate"))
+                      #:user #$user
+                      #:environment-variables
+                      (list (string-append "HOME=" (passwd:dir (getpw #$user)))
+                            "GUIX_SYSTEM_IS_RUNNING_HOME_ACTIVATE=t")
+                      #:group (group:name (getgrgid (passwd:gid (getpw #$user))))))
+            (stop #~(make-kill-destructor)))))
+       config))
+
+(define guix-home-service-type
+  (service-type
+   (name 'guix-home)
+   (description "Setups home-environments specified in the value.")
+   (extensions (list (service-extension
+                      shepherd-root-service-type
+                      guix-home-shepherd-service)))
+   (compose concatenate)
+   (extend append)
+   (default-value '())))
+
 \f
 ;;;
 ;;; Nar Herder

base-commit: 447e9c96259e8fa15a828de9b2dd3400e2ffafe6
-- 
2.41.0

[bug#69781] [PATCH v2] services: Add the Guix Home Service

[Richard Sent]

This patch adds a Guix Home Service, which allows for configuring/deploying an
operating-system declaration with an associated home-environment.

* gnu/services/guix.scm: Add guix-home-service and guix-home-shepherd-service
* gnu/home/services/shepherd.scm: Don't attempt to launch user shepherd when
the system shepherd runs guix-home-<user>
* doc/guix.texi: Add documentation for guix-home-service
* gnu/tests/guix.scm: Add a test to verify guix-home-service-type is able to
activate a home environment

Change-Id: Ifbcc0878d934aa4abe34bb2123b5081fb432aa8e
---

Resubmitting based on feedback on a similar patch that I missed
earlier, https://issues.guix.gnu.org/68589. Not sure how to merge
patches, but figured best to submit V2 to this issue. Sorry!

 doc/guix.texi                  | 32 +++++++++++++++
 gnu/home/services/shepherd.scm |  7 +++-
 gnu/services/guix.scm          | 38 ++++++++++++++++++
 gnu/tests/guix.scm             | 73 ++++++++++++++++++++++++++++++++++
 4 files changed, 149 insertions(+), 1 deletion(-)

diff --git a/doc/guix.texi b/doc/guix.texi
index 20f007b1c0..3a5f1289fa 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -125,6 +125,7 @@
 Copyright @copyright{} 2023 Graham James Addis@*
 Copyright @copyright{} 2023 Tomas Volf@*
 Copyright @copyright{} 2024 Herman Rimm@*
+Copyright @copyright{} 2024 Richard Sent@*
 
 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.3 or
@@ -39576,6 +39577,37 @@ Guix Services
 @end table
 @end deftp
 
+@subsubheading Guix Home Service
+The Guix Home Service allows for associating Guix @ref{Declaring the
+Home Environment, home-environment} declarations with a Guix
+@ref{operating-system Reference, operating-system}.
+
+@defvar guix-home-service-type
+Service type for the Guix Home Service.  Its value must be a list of
+lists containing user and home environment pairs.  The key of each pair
+is a string representing the user to deploy the configuration under and
+the value is a home-environment configuration.
+
+@lisp
+(define my-home
+  (home-environment
+   ...))
+
+(operating-system
+  (services (list
+             (service guix-home-service-type
+                      `(("alice" ,my-home))))))
+@end lisp
+
+This service can be extended by other services to add additional home
+environments, as in this example:
+
+@lisp
+(simple-service 'my-extra-home home-service-type
+                `(("bob" ,my-extra-home))))
+@end lisp
+@end defvar
+
 @subsubheading Nar Herder
 The @uref{https://git.cbaines.net/guix/nar-herder/about/,Nar Herder} is
 a utility for managing a collection of nars.
diff --git a/gnu/home/services/shepherd.scm b/gnu/home/services/shepherd.scm
index 176f4575cb..e68dea6954 100644
--- a/gnu/home/services/shepherd.scm
+++ b/gnu/home/services/shepherd.scm
@@ -132,7 +132,12 @@ (define (ensure-shepherd-gexp config)
               (format #f "/run/user/~a" (getuid)))
           "/shepherd/socket"))
         #$(reload-configuration-gexp config)
-        #$(launch-shepherd-gexp config)))
+        ;; Don't attempt to start user shepherd if the system is running the
+        ;; activation script. /run/user/<uid> may not have been created
+        ;; yet. But do otherwise so if the runtime dir does not exist an error
+        ;; is logged.
+        (unless (getenv "GUIX_SYSTEM_IS_RUNNING_HOME_ACTIVATE")
+          #$(launch-shepherd-gexp config))))
 
 (define (shepherd-xdg-configuration-files config)
   `(("shepherd/init.scm" ,(home-shepherd-configuration-file config))))
diff --git a/gnu/services/guix.scm b/gnu/services/guix.scm
index c438da531c..05ff9f1ba4 100644
--- a/gnu/services/guix.scm
+++ b/gnu/services/guix.scm
@@ -1,5 +1,6 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2019, 2020, 2021, 2022 Christopher Baines <mail@cbaines.net>
+;;; Copyright © 2024 Andrew Tropin <andrew@trop.in>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -101,6 +102,8 @@ (define-module (gnu services guix)
 
             guix-data-service-type
 
+            guix-home-service-type
+
             nar-herder-service-type
             nar-herder-configuration
             nar-herder-configuration?
@@ -686,6 +689,41 @@ (define guix-data-service-type
    (description
     "Run an instance of the Guix Data Service.")))
 
+\f
+;;;
+;;; Guix Home Service
+;;;
+
+(define (guix-home-shepherd-service config)
+  (map (match-lambda
+         ((user he)
+          (shepherd-service
+           (documentation "Activate Guix Home.")
+           (requirement '(user-processes))
+           (provision (list (symbol-append 'guix-home- (string->symbol user))))
+           (one-shot? #t)
+           (auto-start? #t)
+           (start #~(make-forkexec-constructor
+                     '(#$(file-append he "/activate"))
+                     #:user #$user
+                     #:environment-variables
+                     (list (string-append "HOME=" (passwd:dir (getpw #$user)))
+                           "GUIX_SYSTEM_IS_RUNNING_HOME_ACTIVATE=t")
+                     #:group (group:name (getgrgid (passwd:gid (getpw #$user))))))
+           (stop #~(make-kill-destructor)))))
+       config))
+
+(define guix-home-service-type
+  (service-type
+   (name 'guix-home)
+   (description "Sets up Guix Home for the specified user accounts.")
+   (extensions (list (service-extension
+                      shepherd-root-service-type
+                      guix-home-shepherd-service)))
+   (compose concatenate)
+   (extend append)
+   (default-value '())))
+
 \f
 ;;;
 ;;; Nar Herder
diff --git a/gnu/tests/guix.scm b/gnu/tests/guix.scm
index 240ded4825..12ad1bf255 100644
--- a/gnu/tests/guix.scm
+++ b/gnu/tests/guix.scm
@@ -17,6 +17,8 @@
 ;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (gnu tests guix)
+  #:use-module (gnu home)
+  #:use-module (gnu home services)
   #:use-module (gnu tests)
   #:use-module (gnu system)
   #:use-module (gnu system file-systems)
@@ -37,6 +39,7 @@ (define-module (gnu tests guix)
   #:use-module (ice-9 match)
   #:export (%test-guix-build-coordinator
             %test-guix-data-service
+            %test-guix-home-service
             %test-nar-herder
             %test-bffe))
 
@@ -251,6 +254,76 @@ (define %test-guix-data-service
    (description "Connect to a running Guix Data Service.")
    (value (run-guix-data-service-test))))
 
+\f
+;;;
+;;; Guix Home
+;;;
+
+(define %guix-home-service-he
+  (home-environment
+   (services
+    (list (simple-service 'guix-home-service-test
+                          home-files-service-type
+                          `(("guix-home-service-activated"
+                             ,(plain-file "guix-home-service-activated"
+                                          "Guix Home service activated"))))))))
+
+(define %guix-home-service-os
+  (simple-operating-system
+   (service guix-home-service-type
+            `(("alice" ,%guix-home-service-he)))))
+
+(define (run-guix-home-service-test)
+  (define os
+    (marionette-operating-system
+     %guix-home-service-os
+     #:imported-modules '((gnu services herd))))
+
+  (define vm
+    (virtual-machine
+     (operating-system os)
+     (memory-size 1024)))
+
+  (define test
+    (with-imported-modules '((gnu build marionette))
+      #~(begin
+          (use-modules (srfi srfi-64)
+                       (gnu build marionette))
+
+          (define marionette
+            (make-marionette (list #$vm)))
+
+          (test-runner-current (system-test-runner #$output))
+          (test-begin "guix-home-service")
+
+          (test-assert "service started"
+            (marionette-eval
+             '(begin
+                (use-modules (gnu services herd))
+                (match (start-service 'guix-home-alice)
+                  (#f #f)
+                  ;; herd returns (running #f), likely because of one shot,
+                  ;; so consider any non-error a success.
+                  (('service response-parts ...) #t)))
+             marionette))
+
+          (test-assert "file-exists"
+            (marionette-eval
+             '(begin
+                (sleep 3) ;make sure service has time to symlink files
+                (file-exists? "/home/alice/guix-home-service-activated"))
+             marionette))
+
+          (test-end))))
+
+  (gexp->derivation "guix-home-service-test" test))
+
+(define %test-guix-home-service
+  (system-test
+   (name "guix-home-service")
+   (description "Activate a Guix home environment.")
+   (value (run-guix-home-service-test))))
+
 \f
 ;;;
 ;;; Nar Herder

base-commit: 9b84b362963770d7a21ceb4e711a5a389db5b02d
-- 
2.41.0

bug#69781: [PATCH v2] services: Add the Guix Home Service

[Ludovic Courtès]

Hi Richard,

Richard Sent <richard@freakingpenguin.com> skribis:

> This patch adds a Guix Home Service, which allows for configuring/deploying an
> operating-system declaration with an associated home-environment.
>
> * gnu/services/guix.scm: Add guix-home-service and guix-home-shepherd-service
> * gnu/home/services/shepherd.scm: Don't attempt to launch user shepherd when
> the system shepherd runs guix-home-<user>
> * doc/guix.texi: Add documentation for guix-home-service
> * gnu/tests/guix.scm: Add a test to verify guix-home-service-type is able to
> activate a home environment
>
> Change-Id: Ifbcc0878d934aa4abe34bb2123b5081fb432aa8e

This addresses a longstanding user request, nice!

I followed up with a doc update to make the service more discoverable.

Thank you!

Ludo’.

[bug#69781] [PATCH v2] services: Add the Guix Home Service

[Ludovic Courtès]

Hi Richard,

Richard Sent <richard@freakingpenguin.com> skribis:

> This patch adds a Guix Home Service, which allows for configuring/deploying an
> operating-system declaration with an associated home-environment.
>
> * gnu/services/guix.scm: Add guix-home-service and guix-home-shepherd-service
> * gnu/home/services/shepherd.scm: Don't attempt to launch user shepherd when
> the system shepherd runs guix-home-<user>
> * doc/guix.texi: Add documentation for guix-home-service
> * gnu/tests/guix.scm: Add a test to verify guix-home-service-type is able to
> activate a home environment
>
> Change-Id: Ifbcc0878d934aa4abe34bb2123b5081fb432aa8e

I’m using it now, yay!!

I realized there are two issues:

  1. ‘guix system reconfigure’ installs ~/.guix-home, but it doesn’t run
     activation scripts.  So for instance, in my case, ~/.ssh/config
     would remain dangling, pointing to that installed by my previous
     Home generation, and Shepherd services were not reloaded.

  2. ‘guix home describe’ USN’t prepared to deal with that: it returns
     information from the last
     /var/guix/profiles/per-user/$USER/guix-home-*.

#1 is the most problematic.

Thoughts?

Ludo’.

[bug#69781] [PATCH v2] services: Add the Guix Home Service

[Ludovic Courtès]

Ludovic Courtès <ludo@gnu.org> skribis:

>   1. ‘guix system reconfigure’ installs ~/.guix-home, but it doesn’t run
>      activation scripts.  So for instance, in my case, ~/.ssh/config
>      would remain dangling, pointing to that installed by my previous
>      Home generation, and Shepherd services were not reloaded.

Silly me: I was using ‘home-service-type’ instead of
‘guix-home-service-type’. 🤦

(Interestingly, this has no effect at all, but nothing complained,
either.)

Works like a charm after switching to ‘guix-home-service-type’!  :-)

>   2. ‘guix home describe’ isn’t prepared to deal with that: it returns
>      information from the last
>      /var/guix/profiles/per-user/$USER/guix-home-*.

That issue remains, but it’s less of a problem.

Ludo’.

[bug#69781] [PATCH v2] services: Add the Guix Home Service

[Richard Sent]

Hi Ludo!

Ludovic Courtès <ludo@gnu.org> writes:

> Ludovic Courtès <ludo@gnu.org> skribis:
>
> Silly me: I was using ‘home-service-type’ instead of
> ‘guix-home-service-type’. 🤦
>
> (Interestingly, this has no effect at all, but nothing complained,
> either.)
>
> Works like a charm after switching to ‘guix-home-service-type’!  :-)

Thanks for the response! I just started investigating that and was close
to entering the "losing my mind" phase of debugging. Glad to hear it
does in fact work!

>>   2. ‘guix home describe’ isn’t prepared to deal with that: it returns
>>      information from the last
>>      /var/guix/profiles/per-user/$USER/guix-home-*.
>
> That issue remains, but it’s less of a problem.

There are definitely some potential issues when running certain 'guix
home ...' commands that operate on generations while using
'guix-home-service. The "correct" behavior may not always be obvious
either. For example:

1. 'guix-home-service' reactivates the same home environment every time
the service is launched. If generations are created, how should that be
reflected if the user has a home environment activated by
'guix-home-service' (generation A), runs 'guix home reconfigure'
(generation B), and reboots? Consider it a silent roll back to A? Should
B be marked a garbage collection candidate? Or should generation C be
created?

2. Users may try 'guix home roll-back' or 'switch-generations', thinking
the change is persistent. Should this be transient? Or should the change
be made persistent somehow? (I'm strongly in favor of "transient", but I
figured I'd raise the point.)

I think this approach is best:

1. Create a new home generation when 'guix system reconfigure' and
'guix-home-service' are used.

2. Make 'guix home reconfigure', 'switch-generations', and 'roll-back'
all warn that the changes are temporary.

3. Disable 'guix home delete-generations' on any system-created home
generations. System-created home generations are deleted when the
corresponding system generation is deleted.

4. Adjust 'guix home list-generations' and 'describe' to indicate if a
home generation came from a particular system generation.

As for how to accomplish this or how feasible it is? No clue.

-- 
Take it easy,
Richard Sent
Making my computer weirder one commit at a time.