guix/gnu/services/mcron.scm
Ricardo Wurmus 0791437f97
gnu: Move most packages from guile.scm to new module.
* gnu/packages/guile.scm (artanis, guildhall, guile-aspell, guile-bash,
guile-8sync, guile-daemon, guile-dsv, guile-fibers, guile-syntax-highlight,
guile-sjson, guile-colorized, guile-pfds, guile-aa-tree, guile-simple-zmq,
jupyter-guile-kernel, guile-sparql, guile-debbugs, guile-email,
guile-debbugs-next, guile-newt, guile-mastodon, guile-parted, guile-xosd,
guile-dbi, guile-dbd-sqlite3, guile-config, guile-hall, guile-ics, guile-wisp,
guile-sly, g-wrap, guile-miniadapton, guile-reader, guile2.2-reader,
guile-ncurses, guile-ncurses/gpm, guile-lib, guile2.0-lib, guile2.2-lib,
guile-minikanren, guile2.0-minikanren, guile2.2-minikanren, guile-irregex,
guile2.0-irregex, guile2.2-irregex, haunt, guile2.0-haunt, guile2.2-haunt,
guile-redis, guile2.0-redis, guile2.2-redis, guile-commonmark,
guile2.0-commonmark, guile2.2-commonmark, mcron, mcron2): Move these variables
from here...
* gnu/packages/guile-xyz.scm: ...to this new file.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add it.
* gnu/installer.scm,
gnu/packages/bioinformatics.scm,
gnu/packages/ci.scm,
gnu/packages/gtk.scm,
gnu/packages/guile.scm,
gnu/packages/mail.scm,
gnu/packages/package-management.scm,
gnu/packages/skribilo.scm,
gnu/packages/web.scm,
gnu/services/mcron.scm: Update module references.
2019-01-28 14:57:10 +01:00

161 lines
6.1 KiB
Scheme

;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2016, 2017, 2018, 2019 Ludovic Courtès <ludo@gnu.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 services mcron)
#:use-module (gnu services)
#:use-module (gnu services base)
#:use-module (gnu services shepherd)
#:autoload (gnu packages guile-xyz) (mcron)
#: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-service-type
mcron-service))
;;; 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-record-type* <mcron-configuration> mcron-configuration
make-mcron-configuration
mcron-configuration?
(mcron mcron-configuration-mcron ;package
(default mcron))
(jobs mcron-configuration-jobs ;list of <mcron-job>
(default '())))
(define (job-file job)
(scheme-file "mcron-job" job))
(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
(match-lambda
(($ <mcron-configuration> mcron ()) ;nothing to do!
'())
(($ <mcron-configuration> mcron jobs)
(let ((files (map job-file 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 (string-append #$mcron "/bin/mcron") #$@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)))))
(stop #~(make-kill-destructor))
(actions
(list (shepherd-schedule-action mcron files)))))))))
(define mcron-service-type
(service-type (name 'mcron)
(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
(define-deprecated (mcron-service jobs #:optional (mcron mcron))
mcron-service-type
"Return an mcron service running @var{mcron} that schedules @var{jobs}, a
list of gexps denoting mcron job specifications.
This is a shorthand for:
@example
(service mcron-service-type
(mcron-configuration (mcron mcron) (jobs jobs)))
@end example
"
(service mcron-service-type
(mcron-configuration (mcron mcron) (jobs jobs))))
;;; mcron.scm ends here