diff options
| -rw-r--r-- | doc/guix.texi | 78 | ||||
| -rw-r--r-- | gnu/local.mk | 1 | ||||
| -rw-r--r-- | gnu/services/mcron.scm | 115 | ||||
| -rw-r--r-- | gnu/tests/base.scm | 106 |
4 files changed, 299 insertions, 1 deletions
diff --git a/doc/guix.texi b/doc/guix.texi index 0bb68bb477..7516d75b8d 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -204,6 +204,7 @@ System Configuration Services * Base Services:: Essential system services. +* Scheduled Job Execution:: The mcron service. * Networking Services:: Network setup, SSH daemon, etc. * X Window:: Graphical display. * Desktop Services:: D-Bus and desktop services. @@ -7185,6 +7186,7 @@ declaration. @menu * Base Services:: Essential system services. +* Scheduled Job Execution:: The mcron service. * Networking Services:: Network setup, SSH daemon, etc. * X Window:: Graphical display. * Desktop Services:: D-Bus and desktop services. @@ -7463,6 +7465,82 @@ archive}). If that is not the case, the service will fail to start. @end deffn +@node Scheduled Job Execution +@subsubsection Scheduled Job Execution + +@cindex cron +@cindex scheduling jobs +The @code{(gnu services mcron)} module provides an interface to +GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,, +mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional +Unix @command{cron} daemon; the main difference is that it is +implemented in Guile Scheme, which provides a lot of flexibility when +specifying the scheduling of jobs and their actions. + +For example, to define an operating system that runs the +@command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files}) +and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily: + +@lisp +(use-modules (guix) (gnu) (gnu services mcron)) + +(define updatedb-job + ;; Run 'updatedb' at 3 AM every day. + #~(job '(next-hour '(3)) + "updatedb --prunepaths='/tmp /var/tmp /gnu/store'")) + +(define garbage-collector-job + ;; Collect garbage 5 minutes after midnight every day. + #~(job "5 0 * * *" ;Vixie cron syntax + "guix gc -F 1G")) + +(operating-system + ;; @dots{} + (services (cons (mcron-service (list garbage-collector-job + updatedb-job)) + %base-services))) +@end lisp + +@xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron}, +for more information on mcron job specifications. Below is the +reference of the mcron service. + +@deffn {Scheme Procedure} mcron-service @var{jobs} [#:mcron @var{mcron2}] +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 +@end deffn + +@defvr {Scheme Variable} mcron-service-type +This is the type of the @code{mcron} service, whose value is an +@code{mcron-configuration} object. + +This service type can be the target of a service extension that provides +it additional job specifications (@pxref{Service Composition}). In +other words, it is possible to define services that provide addition +mcron jobs to run. +@end defvr + +@deftp {Data Type} mcron-configuration +Data type representing the configuration of mcron. + +@table @asis +@item @code{mcron} (default: @var{mcron2}) +The mcron package to use. + +@item @code{jobs} +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}). +@end table +@end deftp + + @node Networking Services @subsubsection Networking Services diff --git a/gnu/local.mk b/gnu/local.mk index ab0cf49b24..3e0082b8fa 100644 --- a/gnu/local.mk +++ b/gnu/local.mk @@ -377,6 +377,7 @@ GNU_SYSTEM_MODULES = \ %D%/services/dict.scm \ %D%/services/lirc.scm \ %D%/services/mail.scm \ + %D%/services/mcron.scm \ %D%/services/networking.scm \ %D%/services/shepherd.scm \ %D%/services/herd.scm \ diff --git a/gnu/services/mcron.scm b/gnu/services/mcron.scm new file mode 100644 index 0000000000..313c8364f8 --- /dev/null +++ b/gnu/services/mcron.scm @@ -0,0 +1,115 @@ +;;; GNU Guix --- Functional package management for GNU +;;; Copyright © 2016 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) (mcron2) + #: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 mcron2)) + (jobs mcron-configuration-jobs ;list of <mcron-job> + (default '()))) + +(define (job-file job) + (scheme-file "mcron-job" job)) + +(define mcron-shepherd-services + (match-lambda + (($ <mcron-configuration> mcron ()) ;nothing to do! + '()) + (($ <mcron-configuration> mcron jobs) + (list (shepherd-service + (provision '(mcron)) + (requirement '(user-processes)) + (modules `((srfi srfi-1) + (srfi srfi-26) + ,@%default-modules)) + (start #~(make-forkexec-constructor + (list (string-append #$mcron "/bin/mcron") + #$@(map job-file jobs)) + + ;; 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))))))) + +(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))))))) + +(define* (mcron-service jobs #:optional (mcron mcron2)) + "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 diff --git a/gnu/tests/base.scm b/gnu/tests/base.scm index 3dfa28f7f5..8b1fefe9f8 100644 --- a/gnu/tests/base.scm +++ b/gnu/tests/base.scm @@ -24,6 +24,7 @@ #:use-module (gnu system shadow) #:use-module (gnu system vm) #:use-module (gnu services) + #:use-module (gnu services mcron) #:use-module (gnu services shepherd) #:use-module (guix gexp) #:use-module (guix store) @@ -31,7 +32,8 @@ #:use-module (guix packages) #:use-module (srfi srfi-1) #:export (run-basic-test - %test-basic-os)) + %test-basic-os + %test-mcron)) (define %simple-os (operating-system @@ -178,3 +180,105 @@ functionality tests.") ;; 'system-qemu-image/shared-store-script'. (run-basic-test (virtualized-operating-system os '()) #~(list #$run)))))) + + +;;; +;;; Mcron. +;;; + +(define %mcron-os + ;; System with an mcron service, with one mcron job for "root" and one mcron + ;; job for an unprivileged user (note: #:user is an 'mcron2' thing.) + (let ((job1 #~(job next-second-from + (lambda () + (call-with-output-file "witness" + (lambda (port) + (display (list (getuid) (getgid)) port)))))) + (job2 #~(job next-second-from + (lambda () + (call-with-output-file "witness" + (lambda (port) + (display (list (getuid) (getgid)) port)))) + #:user "alice")) + (job3 #~(job next-second-from ;to test $PATH + "touch witness-touch"))) + (operating-system + (inherit %simple-os) + (services (cons (mcron-service (list job1 job2 job3)) + (operating-system-user-services %simple-os)))))) + +(define (run-mcron-test name) + (mlet* %store-monad ((os -> (marionette-operating-system + %mcron-os + #:imported-modules '((gnu services herd) + (guix combinators)))) + (command (system-qemu-image/shared-store-script + os #:graphic? #f))) + (define test + #~(begin + (use-modules (gnu build marionette) + (srfi srfi-64) + (ice-9 match)) + + (define marionette + (make-marionette (list #$command))) + + (define (wait-for-file file) + ;; Wait until FILE exists in the guest; 'read' its content and + ;; return it. + (marionette-eval + `(let loop ((i 10)) + (cond ((file-exists? ,file) + (call-with-input-file ,file read)) + ((> i 0) + (sleep 1) + (loop (- i 1))) + (else + (error "file didn't show up" ,file)))) + marionette)) + + (mkdir #$output) + (chdir #$output) + + (test-begin "mcron") + + (test-eq "service running" + 'running! + (marionette-eval + '(begin + (use-modules (gnu services herd)) + (start-service 'mcron) + 'running!) + marionette)) + + ;; Make sure root's mcron job runs, has its cwd set to "/root", and + ;; runs with the right UID/GID. + (test-equal "root's job" + '(0 0) + (wait-for-file "/root/witness")) + + ;; Likewise for Alice's job. We cannot know what its GID is since + ;; it's chosen by 'groupadd', but it's strictly positive. + (test-assert "alice's job" + (match (wait-for-file "/home/alice/witness") + ((1000 gid) + (>= gid 100)))) + + ;; Last, the job that uses a command; allows us to test whether + ;; $PATH is sane. (Note that 'marionette-eval' stringifies objects + ;; that don't have a read syntax, hence the string.) + (test-equal "root's job with command" + "#<eof>" + (wait-for-file "/root/witness-touch")) + + (test-end) + (exit (= (test-runner-fail-count (test-runner-current)) 0)))) + + (gexp->derivation name test + #:modules '((gnu build marionette))))) + +(define %test-mcron + (system-test + (name "mcron") + (description "Make sure the mcron service works as advertised.") + (value (run-mcron-test name)))) |