mirror of
https://git.in.rschanz.org/ryan77627/guix.git
synced 2024-12-29 07:42:23 -05:00
fa9edf09e9
* gnu/machine.scm: New file. * gnu/machine/ssh.scm: New file. * gnu/local.mk (GNU_SYSTEM_MODULES): Add it.
369 lines
15 KiB
Scheme
369 lines
15 KiB
Scheme
;;; GNU Guix --- Functional package management for GNU
|
||
;;; 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 (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 ssh)
|
||
#:use-module (guix store)
|
||
#:use-module (ice-9 match)
|
||
#:use-module (srfi srfi-19)
|
||
#:use-module (srfi srfi-35)
|
||
#:export (managed-host-environment-type
|
||
|
||
machine-ssh-configuration
|
||
machine-ssh-configuration?
|
||
machine-ssh-configuration
|
||
|
||
machine-ssh-configuration-host-name
|
||
machine-ssh-configuration-port
|
||
machine-ssh-configuration-user
|
||
machine-ssh-configuration-session))
|
||
|
||
;;; Commentary:
|
||
;;;
|
||
;;; This module implements remote evaluation and system deployment for
|
||
;;; machines that are accessable over SSH and have a known host-name. In the
|
||
;;; sense of the broader "machine" interface, we describe the environment for
|
||
;;; such machines as 'managed-host.
|
||
;;;
|
||
;;; Code:
|
||
|
||
|
||
;;;
|
||
;;; Parameters for the SSH client.
|
||
;;;
|
||
|
||
(define-record-type* <machine-ssh-configuration> machine-ssh-configuration
|
||
make-machine-ssh-configuration
|
||
machine-ssh-configuration?
|
||
this-machine-ssh-configuration
|
||
(host-name machine-ssh-configuration-host-name) ; string
|
||
(port machine-ssh-configuration-port ; integer
|
||
(default 22))
|
||
(user machine-ssh-configuration-user ; string
|
||
(default "root"))
|
||
(identity machine-ssh-configuration-identity ; path to a private key
|
||
(default #f))
|
||
(session machine-ssh-configuration-session ; session
|
||
(default #f)))
|
||
|
||
(define (machine-ssh-session machine)
|
||
"Return the SSH session that was given in MACHINE's configuration, or create
|
||
one from the configuration's parameters if one was not provided."
|
||
(maybe-raise-unsupported-configuration-error machine)
|
||
(let ((config (machine-configuration machine)))
|
||
(or (machine-ssh-configuration-session config)
|
||
(let ((host-name (machine-ssh-configuration-host-name config))
|
||
(user (machine-ssh-configuration-user config))
|
||
(port (machine-ssh-configuration-port config))
|
||
(identity (machine-ssh-configuration-identity config)))
|
||
(open-ssh-session host-name
|
||
#:user user
|
||
#:port port
|
||
#:identity identity)))))
|
||
|
||
|
||
;;;
|
||
;;; Remote evaluation.
|
||
;;;
|
||
|
||
(define (managed-host-remote-eval machine exp)
|
||
"Internal implementation of 'machine-remote-eval' for MACHINE instances with
|
||
an environment type of 'managed-host."
|
||
(maybe-raise-unsupported-configuration-error machine)
|
||
(remote-eval exp (machine-ssh-session machine)))
|
||
|
||
|
||
;;;
|
||
;;; 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."
|
||
(define bootable-kernel-arguments
|
||
(@@ (gnu system) bootable-kernel-arguments))
|
||
|
||
(define remote-exp
|
||
(with-extensions (list guile-gcrypt)
|
||
(with-imported-modules (source-module-closure '((guix config)
|
||
(guix profiles)))
|
||
#~(begin
|
||
(use-modules (guix config)
|
||
(guix profiles)
|
||
(ice-9 textual-ports))
|
||
|
||
(define %system-profile
|
||
(string-append %state-directory "/profiles/system"))
|
||
|
||
(define (read-file path)
|
||
(call-with-input-file path
|
||
(lambda (port)
|
||
(get-string-all port))))
|
||
|
||
(map (lambda (generation)
|
||
(let* ((system-path (generation-file-name %system-profile
|
||
generation))
|
||
(boot-parameters-path (string-append system-path
|
||
"/parameters"))
|
||
(time (stat:mtime (lstat system-path))))
|
||
(list generation
|
||
system-path
|
||
time
|
||
(read-file boot-parameters-path))))
|
||
(reverse (generation-numbers %system-profile)))))))
|
||
|
||
(mlet* %store-monad ((generations (machine-remote-eval machine remote-exp)))
|
||
(return
|
||
(map (lambda (generation)
|
||
(match generation
|
||
((generation system-path time serialized-params)
|
||
(let* ((params (call-with-input-string serialized-params
|
||
read-boot-parameters))
|
||
(root (boot-parameters-root-device params))
|
||
(label (boot-parameters-label params)))
|
||
(boot-parameters
|
||
(inherit params)
|
||
(label
|
||
(string-append label " (#"
|
||
(number->string generation) ", "
|
||
(let ((time (make-time time-utc 0 time)))
|
||
(date->string (time-utc->date time)
|
||
"~Y-~m-~d ~H:~M"))
|
||
")"))
|
||
(kernel-arguments
|
||
(append (bootable-kernel-arguments system-path root)
|
||
(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)
|
||
(mbegin %store-monad
|
||
(switch-to-system machine)
|
||
(upgrade-shepherd-services machine)
|
||
(install-bootloader machine)))
|
||
|
||
|
||
;;;
|
||
;;; Environment type.
|
||
;;;
|
||
|
||
(define managed-host-environment-type
|
||
(environment-type
|
||
(machine-remote-eval managed-host-remote-eval)
|
||
(deploy-machine deploy-managed-host)
|
||
(name 'managed-host-environment-type)
|
||
(description "Provisioning for machines that are accessable over SSH
|
||
and have a known host-name. This entails little more than maintaining an SSH
|
||
connection to the host.")))
|
||
|
||
(define (maybe-raise-unsupported-configuration-error machine)
|
||
"Raise an error if MACHINE's configuration is not an instance of
|
||
<machine-ssh-configuration>."
|
||
(let ((config (machine-configuration machine))
|
||
(environment (environment-type-name (machine-environment machine))))
|
||
(unless (and config (machine-ssh-configuration? config))
|
||
(raise (condition
|
||
(&message
|
||
(message (format #f (G_ "unsupported machine configuration '~a'
|
||
for environment of type '~a'")
|
||
config
|
||
environment))))))))
|