guix system: Add 'reconfigure' module.

* guix/scripts/system/reconfigure.scm: New file.
* Makefile.am (MODULES): Add it.
* guix/scripts/system.scm (bootloader-installer-script): Export variable.
* gnu/machine/ssh.scm (switch-to-system, upgrade-shepherd-services)
(install-bootloader): Delete variable.
* gnu/machine/ssh.scm (deploy-managed-host): Rewrite procedure.
* gnu/services/herd.scm (live-service): Export variable.
* gnu/services/herd.scm (live-service-canonical-name): New variable.
* tests/services.scm (live-service): Delete variable.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>
This commit is contained in:
Jakob L. Kreuze 2019-07-24 12:34:02 -04:00 committed by Ludovic Courtès
parent 20269b6e08
commit 5c793753b3
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5 changed files with 256 additions and 181 deletions

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@ -249,6 +249,7 @@ MODULES = \
guix/scripts/describe.scm \
guix/scripts/system.scm \
guix/scripts/system/search.scm \
guix/scripts/system/reconfigure.scm \
guix/scripts/lint.scm \
guix/scripts/challenge.scm \
guix/scripts/import/crate.scm \

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@ -17,23 +17,21 @@
;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
(define-module (gnu machine ssh)
#:use-module (gnu bootloader)
#:use-module (gnu machine)
#:autoload (gnu packages gnupg) (guile-gcrypt)
#:use-module (gnu services)
#:use-module (gnu services shepherd)
#:use-module (gnu system)
#:use-module (guix derivations)
#:use-module (guix gexp)
#:use-module (guix i18n)
#:use-module (guix modules)
#:use-module (guix monads)
#:use-module (guix records)
#:use-module (guix remote)
#:use-module (guix scripts system reconfigure)
#:use-module (guix ssh)
#:use-module (guix store)
#:use-module (ice-9 match)
#:use-module (srfi srfi-19)
#:use-module (srfi srfi-26)
#:use-module (srfi srfi-35)
#:export (managed-host-environment-type
@ -105,118 +103,6 @@ an environment type of 'managed-host."
;;; System deployment.
;;;
(define (switch-to-system machine)
"Monadic procedure creating a new generation on MACHINE and execute the
activation script for the new system configuration."
(define (remote-exp drv script)
(with-extensions (list guile-gcrypt)
(with-imported-modules (source-module-closure '((guix config)
(guix profiles)
(guix utils)))
#~(begin
(use-modules (guix config)
(guix profiles)
(guix utils))
(define %system-profile
(string-append %state-directory "/profiles/system"))
(let* ((system #$drv)
(number (1+ (generation-number %system-profile)))
(generation (generation-file-name %system-profile number)))
(switch-symlinks generation system)
(switch-symlinks %system-profile generation)
;; The implementation of 'guix system reconfigure' saves the
;; load path and environment here. This is unnecessary here
;; because each invocation of 'remote-eval' runs in a distinct
;; Guile REPL.
(setenv "GUIX_NEW_SYSTEM" system)
;; The activation script may write to stdout, which confuses
;; 'remote-eval' when it attempts to read a result from the
;; remote REPL. We work around this by forcing the output to a
;; string.
(with-output-to-string
(lambda ()
(primitive-load #$script))))))))
(let* ((os (machine-system machine))
(script (operating-system-activation-script os)))
(mlet* %store-monad ((drv (operating-system-derivation os)))
(machine-remote-eval machine (remote-exp drv script)))))
;; XXX: Currently, this does NOT attempt to restart running services. This is
;; also the case with 'guix system reconfigure'.
;;
;; See <https://issues.guix.info/issue/33508>.
(define (upgrade-shepherd-services machine)
"Monadic procedure unloading and starting services on the remote as needed
to realize the MACHINE's system configuration."
(define target-services
;; Monadic expression evaluating to a list of (name output-path) pairs for
;; all of MACHINE's services.
(mapm %store-monad
(lambda (service)
(mlet %store-monad ((file ((compose lower-object
shepherd-service-file)
service)))
(return (list (shepherd-service-canonical-name service)
(derivation->output-path file)))))
(service-value
(fold-services (operating-system-services (machine-system machine))
#:target-type shepherd-root-service-type))))
(define (remote-exp target-services)
(with-imported-modules '((gnu services herd))
#~(begin
(use-modules (gnu services herd)
(srfi srfi-1))
(define running
(filter live-service-running (current-services)))
(define (essential? service)
;; Return #t if SERVICE is essential and should not be unloaded
;; under any circumstance.
(memq (first (live-service-provision service))
'(root shepherd)))
(define (obsolete? service)
;; Return #t if SERVICE can be safely unloaded.
(and (not (essential? service))
(every (lambda (requirements)
(not (memq (first (live-service-provision service))
requirements)))
(map live-service-requirement running))))
(define to-unload
(filter obsolete?
(remove (lambda (service)
(memq (first (live-service-provision service))
(map first '#$target-services)))
running)))
(define to-start
(remove (lambda (service-pair)
(memq (first service-pair)
(map (compose first live-service-provision)
running)))
'#$target-services))
;; Unload obsolete services.
(for-each (lambda (service)
(false-if-exception
(unload-service service)))
to-unload)
;; Load the service files for any new services and start them.
(load-services/safe (map second to-start))
(for-each start-service (map first to-start))
#t)))
(mlet %store-monad ((target-services target-services))
(machine-remote-eval machine (remote-exp target-services))))
(define (machine-boot-parameters machine)
"Monadic procedure returning a list of 'boot-parameters' for the generations
of MACHINE's system profile, ordered from most recent to oldest."
@ -275,71 +161,20 @@ of MACHINE's system profile, ordered from most recent to oldest."
(boot-parameters-kernel-arguments params))))))))
generations))))
(define (install-bootloader machine)
"Create a bootloader entry for the new system generation on MACHINE, and
configure the bootloader to boot that generation by default."
(define bootloader-installer-script
(@@ (guix scripts system) bootloader-installer-script))
(define (remote-exp installer bootcfg bootcfg-file)
(with-extensions (list guile-gcrypt)
(with-imported-modules (source-module-closure '((gnu build install)
(guix store)
(guix utils)))
#~(begin
(use-modules (gnu build install)
(guix store)
(guix utils))
(let* ((gc-root (string-append "/" %gc-roots-directory "/bootcfg"))
(temp-gc-root (string-append gc-root ".new")))
(switch-symlinks temp-gc-root gc-root)
(unless (false-if-exception
(begin
;; The implementation of 'guix system reconfigure'
;; saves the load path here. This is unnecessary here
;; because each invocation of 'remote-eval' runs in a
;; distinct Guile REPL.
(install-boot-config #$bootcfg #$bootcfg-file "/")
;; The installation script may write to stdout, which
;; confuses 'remote-eval' when it attempts to read a
;; result from the remote REPL. We work around this
;; by forcing the output to a string.
(with-output-to-string
(lambda ()
(primitive-load #$installer)))))
(delete-file temp-gc-root)
(error "failed to install bootloader"))
(rename-file temp-gc-root gc-root)
#t)))))
(mlet* %store-monad ((boot-parameters (machine-boot-parameters machine)))
(let* ((os (machine-system machine))
(bootloader ((compose bootloader-configuration-bootloader
operating-system-bootloader)
os))
(bootloader-target (bootloader-configuration-target
(operating-system-bootloader os)))
(installer (bootloader-installer-script
(bootloader-installer bootloader)
(bootloader-package bootloader)
bootloader-target
"/"))
(menu-entries (map boot-parameters->menu-entry boot-parameters))
(bootcfg (operating-system-bootcfg os menu-entries))
(bootcfg-file (bootloader-configuration-file bootloader)))
(machine-remote-eval machine (remote-exp installer bootcfg bootcfg-file)))))
(define (deploy-managed-host machine)
"Internal implementation of 'deploy-machine' for MACHINE instances with an
environment type of 'managed-host."
(maybe-raise-unsupported-configuration-error machine)
(mlet %store-monad ((boot-parameters (machine-boot-parameters machine)))
(let* ((os (machine-system machine))
(eval (cut machine-remote-eval machine <>))
(menu-entries (map boot-parameters->menu-entry boot-parameters))
(bootloader-configuration (operating-system-bootloader os))
(bootcfg (operating-system-bootcfg os menu-entries)))
(mbegin %store-monad
(switch-to-system machine)
(upgrade-shepherd-services machine)
(install-bootloader machine)))
(switch-to-system eval os)
(upgrade-shepherd-services eval os)
(install-bootloader eval bootloader-configuration bootcfg)))))
;;;

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@ -40,10 +40,12 @@
unknown-shepherd-error?
unknown-shepherd-error-sexp
live-service
live-service?
live-service-provision
live-service-requirement
live-service-running
live-service-canonical-name
with-shepherd-action
current-services
@ -192,6 +194,10 @@ of pairs."
(requirement live-service-requirement) ;list of symbols
(running live-service-running)) ;#f | object
(define (live-service-canonical-name service)
"Return the 'canonical name' of SERVICE."
(first (live-service-provision service)))
(define (current-services)
"Return the list of currently defined Shepherd services, represented as
<live-service> objects. Return #f if the list of services could not be

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@ -0,0 +1,237 @@
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2014, 2015, 2016, 2017, 2018, 2019 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2016 Alex Kost <alezost@gmail.com>
;;; Copyright © 2016, 2017, 2018 Chris Marusich <cmmarusich@gmail.com>
;;; Copyright © 2017 Mathieu Othacehe <m.othacehe@gmail.com>
;;; Copyright © 2018 Ricardo Wurmus <rekado@elephly.net>
;;; Copyright © 2019 Christopher Baines <mail@cbaines.net>
;;; Copyright © 2019 Jakob L. Kreuze <zerodaysfordays@sdf.lonestar.org>
;;;
;;; 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 (guix scripts system reconfigure)
#:autoload (gnu packages gnupg) (guile-gcrypt)
#:use-module (gnu bootloader)
#:use-module (gnu services)
#:use-module (gnu services herd)
#:use-module (gnu services shepherd)
#:use-module (gnu system)
#:use-module (guix gexp)
#:use-module (guix modules)
#:use-module (guix monads)
#:use-module (guix store)
#:use-module (ice-9 match)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-11)
#:export (switch-system-program
switch-to-system
upgrade-services-program
upgrade-shepherd-services
install-bootloader-program
install-bootloader))
;;; Commentary:
;;;
;;; This module implements the "effectful" parts of system
;;; reconfiguration. Although building a system derivation is a pure
;;; operation, a number of impure operations must be carried out for the
;;; system configuration to be realized -- chiefly, creation of generation
;;; symlinks and invocation of activation scripts.
;;;
;;; Code:
;;;
;;; Profile creation.
;;;
(define* (switch-system-program os #:optional profile)
"Return an executable store item that, upon being evaluated, will create a
new generation of PROFILE pointing to the directory of OS, switch to it
atomically, and run OS's activation script."
(program-file
"switch-to-system.scm"
(with-extensions (list guile-gcrypt)
(with-imported-modules (source-module-closure '((guix config)
(guix profiles)
(guix utils)))
#~(begin
(use-modules (guix config)
(guix profiles)
(guix utils))
(define profile
(or #$profile (string-append %state-directory "/profiles/system")))
(let* ((number (1+ (generation-number profile)))
(generation (generation-file-name profile number)))
(switch-symlinks generation #$os)
(switch-symlinks profile generation)
(setenv "GUIX_NEW_SYSTEM" #$os)
(primitive-load #$(operating-system-activation-script os))))))))
(define* (switch-to-system eval os #:optional profile)
"Using EVAL, a monadic procedure taking a single G-Expression as an argument,
create a new generation of PROFILE pointing to the directory of OS, switch to
it atomically, and run OS's activation script."
(eval #~(primitive-load #$(switch-system-program os profile))))
;;;
;;; Services.
;;;
(define (running-services eval)
"Using EVAL, a monadic procedure taking a single G-Expression as an argument,
return the <live-service> objects that are currently running on MACHINE."
(define exp
(with-imported-modules '((gnu services herd))
#~(begin
(use-modules (gnu services herd))
(let ((services (current-services)))
(and services
;; 'live-service-running' is ignored, as we can't necessarily
;; serialize arbitrary objects. This should be fine for now,
;; since 'machine-current-services' is not exposed publicly,
;; and the resultant <live-service> objects are only used for
;; resolving service dependencies.
(map (lambda (service)
(list (live-service-provision service)
(live-service-requirement service)))
services))))))
(mlet %store-monad ((services (eval exp)))
(return (map (match-lambda
((provision requirement)
(live-service provision requirement #f)))
services))))
;; XXX: Currently, this does NOT attempt to restart running services. See
;; <https://issues.guix.info/issue/33508> for details.
(define (upgrade-services-program service-files to-start to-unload to-restart)
"Return an executable store item that, upon being evaluated, will upgrade
the Shepherd (PID 1) by unloading obsolete services and loading new
services. SERVICE-FILES is a list of Shepherd service files to load, and
TO-START, TO-UNLOAD, and TO-RESTART are lists of the Shepherd services'
canonical names (symbols)."
(program-file
"upgrade-shepherd-services.scm"
(with-imported-modules '((gnu services herd))
#~(begin
(use-modules (gnu services herd)
(srfi srfi-1))
;; Load the service files for any new services.
(load-services/safe '#$service-files)
;; Unload obsolete services and start new services.
(for-each unload-service '#$to-unload)
(for-each start-service '#$to-start)))))
(define* (upgrade-shepherd-services eval os)
"Using EVAL, a monadic procedure taking a single G-Expression as an argument,
upgrade the Shepherd (PID 1) by unloading obsolete services and loading new
services as defined by OS."
(define target-services
(service-value
(fold-services (operating-system-services os)
#:target-type shepherd-root-service-type)))
(mlet* %store-monad ((live-services (running-services eval)))
(let*-values (((to-unload to-restart)
(shepherd-service-upgrade live-services target-services)))
(let* ((to-unload (map live-service-canonical-name to-unload))
(to-restart (map shepherd-service-canonical-name to-restart))
(to-start (lset-difference eqv?
(map shepherd-service-canonical-name
target-services)
(map live-service-canonical-name
live-services)))
(service-files
(map shepherd-service-file
(filter (lambda (service)
(memq (shepherd-service-canonical-name service)
to-start))
target-services))))
(eval #~(primitive-load #$(upgrade-services-program service-files
to-start
to-unload
to-restart)))))))
;;;
;;; Bootloader configuration.
;;;
(define (install-bootloader-program installer bootloader-package bootcfg
bootcfg-file device target)
"Return an executable store item that, upon being evaluated, will install
BOOTCFG to BOOTCFG-FILE, a target file name, on DEVICE, a file system device,
at TARGET, a mount point, and subsequently run INSTALLER from
BOOTLOADER-PACKAGE."
(program-file
"install-bootloader.scm"
(with-extensions (list guile-gcrypt)
(with-imported-modules (source-module-closure '((gnu build bootloader)
(gnu build install)
(guix store)
(guix utils)))
#~(begin
(use-modules (gnu build bootloader)
(gnu build install)
(guix build utils)
(guix store)
(guix utils)
(ice-9 binary-ports)
(srfi srfi-34)
(srfi srfi-35))
(let* ((gc-root (string-append #$target %gc-roots-directory "/bootcfg"))
(temp-gc-root (string-append gc-root ".new")))
(switch-symlinks temp-gc-root gc-root)
(install-boot-config #$bootcfg #$bootcfg-file #$target)
;; Preserve the previous activation's garbage collector root
;; until the bootloader installer has run, so that a failure in
;; the bootloader's installer script doesn't leave the user with
;; a broken installation.
(when #$installer
(catch #t
(lambda ()
(#$installer #$bootloader-package #$device #$target))
(lambda args
(delete-file temp-gc-root)
(apply throw args))))
(rename-file temp-gc-root gc-root)))))))
(define* (install-bootloader eval configuration bootcfg
#:key
(run-installer? #t)
(target "/"))
"Using EVAL, a monadic procedure taking a single G-Expression as an argument,
configure the bootloader on TARGET such that OS will be booted by default and
additional configurations specified by MENU-ENTRIES can be selected."
(let* ((bootloader (bootloader-configuration-bootloader configuration))
(installer (and run-installer?
(bootloader-installer bootloader)))
(package (bootloader-package bootloader))
(device (bootloader-configuration-target configuration))
(bootcfg-file (bootloader-configuration-file bootloader)))
(eval #~(primitive-load #$(install-bootloader-program installer
package
bootcfg
bootcfg-file
device
target)))))

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@ -26,10 +26,6 @@
#:use-module (srfi srfi-64)
#:use-module (ice-9 match))
(define live-service
(@@ (gnu services herd) live-service))
(test-begin "services")
(test-equal "services, default value"