mirror of
https://git.in.rschanz.org/ryan77627/guix.git
synced 2024-12-24 05:18:07 -05:00
c88582a674
* doc/guix.texi (Scheduled Job Execution): Document it. * gnu/services/mcron.scm (mcron-configuration)[log-file, date-format]: New field. (mcron-shepherd-services): Add log-file and date-format support. Use file-append instead of string-append. Signed-off-by: Maxim Cournoyer <maxim.cournoyer@gmail.com>
223 lines
8.6 KiB
Scheme
223 lines
8.6 KiB
Scheme
;;; GNU Guix --- Functional package management for GNU
|
||
;;; Copyright © 2016, 2017, 2018, 2019, 2020 Ludovic Courtès <ludo@gnu.org>
|
||
;;; Copyright © 2022 Maxim Cournoyer <maxim.cournoyer@gmail.com>
|
||
;;; Copyright © 2023 Bruno Victal <mirai@makinata.eu>
|
||
;;;
|
||
;;; 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 services mcron)
|
||
#:use-module (gnu services)
|
||
#:use-module (gnu services configuration)
|
||
#:use-module (gnu services shepherd)
|
||
#:use-module (gnu packages guile-xyz)
|
||
#:use-module (guix deprecation)
|
||
#:use-module (guix records)
|
||
#:use-module (guix gexp)
|
||
#:use-module (srfi srfi-1)
|
||
#:use-module (ice-9 match)
|
||
#:use-module (ice-9 vlist)
|
||
#:export (mcron-configuration
|
||
mcron-configuration?
|
||
mcron-configuration-mcron
|
||
mcron-configuration-jobs
|
||
mcron-configuration-log?
|
||
mcron-configuration-log-file
|
||
mcron-configuration-log-format
|
||
mcron-configuration-date-format
|
||
|
||
mcron-service-type))
|
||
|
||
;;; Commentary:
|
||
;;;
|
||
;;; This module implements a service that to run instances of GNU mcron, a
|
||
;;; periodic job execution daemon. Example of a service:
|
||
;;
|
||
;; (service mcron-service-type
|
||
;; (mcron-configuration
|
||
;; (jobs (list #~(job next-second-from
|
||
;; (lambda ()
|
||
;; (call-with-output-file "/dev/console"
|
||
;; (lambda (port)
|
||
;; (display "hello!\n" port)))))))))
|
||
;;;
|
||
;;; Code:
|
||
|
||
(define list-of-gexps?
|
||
(list-of gexp?))
|
||
|
||
(define-maybe/no-serialization string)
|
||
|
||
(define-configuration/no-serialization mcron-configuration
|
||
(mcron
|
||
(file-like mcron)
|
||
"The mcron package to use.")
|
||
|
||
(jobs
|
||
(list-of-gexps '())
|
||
"This is a list of gexps (@pxref{G-Expressions}), where each gexp
|
||
corresponds to an mcron job specification (@pxref{Syntax, mcron job
|
||
specifications,, mcron, GNU@tie{}mcron}).")
|
||
|
||
(log?
|
||
(boolean #t)
|
||
"Log messages to standard output.")
|
||
|
||
(log-file
|
||
(string "/var/log/mcron.log")
|
||
"Log file location.")
|
||
|
||
(log-format
|
||
(string "~1@*~a ~a: ~a~%")
|
||
"@code{(ice-9 format)} format string for log messages. The default value
|
||
produces messages like @samp{@var{pid} @var{name}: @var{message}}
|
||
(@pxref{Invoking mcron, Invoking,, mcron, GNU@tie{}mcron}).
|
||
Each message is also prefixed by a timestamp by GNU Shepherd.")
|
||
|
||
(date-format
|
||
maybe-string
|
||
"@code{(srfi srfi-19)} format string for date."))
|
||
|
||
(define (job-files mcron jobs)
|
||
"Return a list of file-like object for JOBS, a list of gexps."
|
||
(define (validated-file job)
|
||
;; This procedure behaves like 'scheme-file' but it runs 'mcron
|
||
;; --schedule' to detect any error in JOB.
|
||
(computed-file "mcron-job"
|
||
(with-imported-modules '((guix build utils))
|
||
#~(begin
|
||
(use-modules (guix build utils))
|
||
|
||
(call-with-output-file "prologue"
|
||
(lambda (port)
|
||
;; This prologue allows 'mcron --schedule' to
|
||
;; proceed no matter what #:user option is passed
|
||
;; to 'job'.
|
||
(write '(set! getpw
|
||
(const (getpwuid (getuid))))
|
||
port)))
|
||
|
||
(call-with-output-file "job"
|
||
(lambda (port)
|
||
(write '#$job port)))
|
||
|
||
(invoke #+(file-append mcron "/bin/mcron")
|
||
"--schedule=20" "prologue" "job")
|
||
(copy-file "job" #$output)))
|
||
#:options '(#:env-vars (("COLUMNS" . "150")))))
|
||
|
||
(map validated-file jobs))
|
||
|
||
(define (shepherd-schedule-action mcron files)
|
||
"Return a Shepherd action that runs MCRON with '--schedule' for the given
|
||
files."
|
||
(shepherd-action
|
||
(name 'schedule)
|
||
(documentation
|
||
"Display jobs that are going to be scheduled.")
|
||
(procedure
|
||
#~(lambda* (_ #:optional (n "5"))
|
||
;; XXX: This is a global side effect.
|
||
(setenv "GUILE_AUTO_COMPILE" "0")
|
||
|
||
;; Run 'mcron' in a pipe so we can explicitly redirect its output to
|
||
;; 'current-output-port', which at this stage is bound to the client
|
||
;; connection.
|
||
(let ((pipe (open-pipe* OPEN_READ
|
||
#$(file-append mcron "/bin/mcron")
|
||
(string-append "--schedule=" n)
|
||
#$@files)))
|
||
(let loop ()
|
||
(match (read-line pipe 'concat)
|
||
((? eof-object?)
|
||
(catch 'system-error
|
||
(lambda ()
|
||
(zero? (close-pipe pipe)))
|
||
(lambda args
|
||
;; There's a race with the SIGCHLD handler, which
|
||
;; could call 'waitpid' before 'close-pipe' above does. If
|
||
;; we get ECHILD, that means we lost the race, but that's
|
||
;; fine.
|
||
(or (= ECHILD (system-error-errno args))
|
||
(apply throw args)))))
|
||
(line
|
||
(display line)
|
||
(loop)))))))))
|
||
|
||
(define (mcron-shepherd-services config)
|
||
(match-record config <mcron-configuration>
|
||
(mcron jobs log? log-file log-format date-format)
|
||
(if (eq? jobs '())
|
||
'() ;nothing to do
|
||
(let ((files (job-files mcron jobs)))
|
||
(list (shepherd-service
|
||
(provision '(mcron))
|
||
(requirement '(user-processes))
|
||
(modules `((srfi srfi-1)
|
||
(srfi srfi-26)
|
||
(ice-9 popen) ;for the 'schedule' action
|
||
(ice-9 rdelim)
|
||
(ice-9 match)
|
||
,@%default-modules))
|
||
(start #~(make-forkexec-constructor
|
||
(list #$(file-append mcron "/bin/mcron")
|
||
#$@(if log?
|
||
`("--log" "--log-format" ,log-format
|
||
,@(if (maybe-value-set? date-format)
|
||
(list "--date-format"
|
||
date-format)
|
||
'()))
|
||
'())
|
||
#$@files)
|
||
|
||
;; Disable auto-compilation of the job files and
|
||
;; set a sane value for 'PATH'.
|
||
#:environment-variables
|
||
(cons* "GUILE_AUTO_COMPILE=0"
|
||
"PATH=/run/current-system/profile/bin"
|
||
(remove (cut string-prefix? "PATH=" <>)
|
||
(environ)))
|
||
|
||
#:log-file #$log-file))
|
||
(stop #~(make-kill-destructor))
|
||
(actions
|
||
(list (shepherd-schedule-action mcron files)))))))))
|
||
|
||
(define mcron-service-type
|
||
(service-type (name 'mcron)
|
||
(description
|
||
"Run the mcron job scheduling daemon.")
|
||
(extensions
|
||
(list (service-extension shepherd-root-service-type
|
||
mcron-shepherd-services)
|
||
(service-extension profile-service-type
|
||
(compose list
|
||
mcron-configuration-mcron))))
|
||
(compose concatenate)
|
||
(extend (lambda (config jobs)
|
||
(mcron-configuration
|
||
(inherit config)
|
||
(jobs (append (mcron-configuration-jobs config)
|
||
jobs)))))
|
||
(default-value (mcron-configuration)))) ;empty job list
|
||
|
||
|
||
;;;
|
||
;;; Generate documentation.
|
||
;;;
|
||
(define (generate-doc)
|
||
(configuration->documentation 'mcron-configuration))
|
||
|
||
;;; mcron.scm ends here
|