752 lines
29 KiB
Scheme
752 lines
29 KiB
Scheme
;;; GNU Guix --- Functional package management for GNU
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;;; Copyright © 2014, 2015, 2016 Ludovic Courtès <ludo@gnu.org>
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;;;
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;;; This file is part of GNU Guix.
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;;;
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;;; GNU Guix is free software; you can redistribute it and/or modify it
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;;; under the terms of the GNU General Public License as published by
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;;; the Free Software Foundation; either version 3 of the License, or (at
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;;; your option) any later version.
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;;;
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;;; GNU Guix is distributed in the hope that it will be useful, but
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;;; WITHOUT ANY WARRANTY; without even the implied warranty of
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;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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;;; GNU General Public License for more details.
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;;;
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;;; You should have received a copy of the GNU General Public License
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;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
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(define-module (guix scripts offload)
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#:use-module (guix config)
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#:use-module (guix records)
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#:use-module (guix store)
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#:use-module (guix derivations)
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#:use-module (guix serialization)
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#:use-module (guix nar)
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#:use-module (guix utils)
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#:use-module ((guix build syscalls) #:select (fcntl-flock))
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#:use-module ((guix build utils) #:select (which mkdir-p))
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#:use-module (guix ui)
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#:use-module (srfi srfi-1)
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#:use-module (srfi srfi-11)
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#:use-module (srfi srfi-26)
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#:use-module (srfi srfi-34)
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#:use-module (srfi srfi-35)
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#:use-module (ice-9 popen)
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#:use-module (ice-9 rdelim)
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#:use-module (ice-9 match)
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#:use-module (ice-9 regex)
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#:use-module (ice-9 format)
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#:use-module (rnrs io ports)
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#:export (build-machine
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build-requirements
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guix-offload))
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;;; Commentary:
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;;;
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;;; Attempt to offload builds to the machines listed in
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;;; /etc/guix/machines.scm, transferring missing dependencies over SSH, and
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;;; retrieving the build output(s) over SSH upon success.
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;;;
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;;; This command should not be used directly; instead, it is called on-demand
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;;; by the daemon, unless it was started with '--no-build-hook' or a client
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;;; inhibited build hooks.
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;;;
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;;; Code:
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(define-record-type* <build-machine>
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build-machine make-build-machine
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build-machine?
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(name build-machine-name) ; string
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(port build-machine-port ; number
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(default 22))
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(system build-machine-system) ; string
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(user build-machine-user) ; string
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(private-key build-machine-private-key ; file name
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(default (user-lsh-private-key)))
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(parallel-builds build-machine-parallel-builds ; number
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(default 1))
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(speed build-machine-speed ; inexact real
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(default 1.0))
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(features build-machine-features ; list of strings
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(default '()))
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(ssh-options build-machine-ssh-options ; list of strings
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(default '())))
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(define-record-type* <build-requirements>
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build-requirements make-build-requirements
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build-requirements?
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(system build-requirements-system) ; string
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(features build-requirements-features ; list of strings
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(default '())))
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(define %machine-file
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;; File that lists machines available as build slaves.
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(string-append %config-directory "/machines.scm"))
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(define %lsh-command
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"lsh")
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(define %lshg-command
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;; FIXME: 'lshg' fails to pass large amounts of data, see
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;; <http://lists.lysator.liu.se/pipermail/lsh-bugs/2014q1/000639.html>.
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"lsh")
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(define (user-lsh-private-key)
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"Return the user's default lsh private key, or #f if it could not be
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determined."
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(and=> (getenv "HOME")
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(cut string-append <> "/.lsh/identity")))
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(define %user-module
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;; Module in which the machine description file is loaded.
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(let ((module (make-fresh-user-module)))
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(module-use! module (resolve-interface '(guix scripts offload)))
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module))
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(define* (build-machines #:optional (file %machine-file))
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"Read the list of build machines from FILE and return it."
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(catch #t
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(lambda ()
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;; Avoid ABI incompatibility with the <build-machine> record.
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(set! %fresh-auto-compile #t)
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(save-module-excursion
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(lambda ()
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(set-current-module %user-module)
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(primitive-load file))))
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(lambda args
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(match args
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(('system-error . _)
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(let ((err (system-error-errno args)))
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;; Silently ignore missing file since this is a common case.
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(if (= ENOENT err)
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'()
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(leave (_ "failed to open machine file '~a': ~a~%")
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file (strerror err)))))
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(('syntax-error proc message properties form . rest)
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(let ((loc (source-properties->location properties)))
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(leave (_ "~a: ~a~%")
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(location->string loc) message)))
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(_
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(leave (_ "failed to load machine file '~a': ~s~%")
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file args))))))
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;;; FIXME: The idea was to open the connection to MACHINE once for all, but
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;;; lshg is currently non-functional.
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;; (define (open-ssh-gateway machine)
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;; "Initiate an SSH connection gateway to MACHINE, and return the PID of the
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;; running lsh gateway upon success, or #f on failure."
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;; (catch 'system-error
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;; (lambda ()
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;; (let* ((port (open-pipe* OPEN_READ %lsh-command
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;; "-l" (build-machine-user machine)
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;; "-i" (build-machine-private-key machine)
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;; ;; XXX: With lsh 2.1, passing '--write-pid'
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;; ;; last causes the PID not to be printed.
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;; "--write-pid" "--gateway" "--background"
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;; (build-machine-name machine)))
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;; (line (read-line port))
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;; (status (close-pipe port)))
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;; (if (zero? status)
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;; (let ((pid (string->number line)))
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;; (if (integer? pid)
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;; pid
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;; (begin
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;; (warning (_ "'~a' did not write its PID on stdout: ~s~%")
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;; %lsh-command line)
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;; #f)))
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;; (begin
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;; (warning (_ "failed to initiate SSH connection to '~a':\
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;; '~a' exited with ~a~%")
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;; (build-machine-name machine)
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;; %lsh-command
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;; (status:exit-val status))
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;; #f))))
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;; (lambda args
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;; (leave (_ "failed to execute '~a': ~a~%")
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;; %lsh-command (strerror (system-error-errno args))))))
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(define-syntax with-error-to-port
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(syntax-rules ()
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((_ port exp0 exp ...)
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(let ((new port)
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(old (current-error-port)))
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(dynamic-wind
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(lambda ()
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(set-current-error-port new))
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(lambda ()
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exp0 exp ...)
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(lambda ()
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(set-current-error-port old)))))))
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(define* (remote-pipe machine mode command
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#:key (error-port (current-error-port)) (quote? #t))
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"Run COMMAND (a string list) on MACHINE, assuming an lsh gateway has been
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set up. When QUOTE? is true, perform shell-quotation of all the elements of
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COMMAND. Return either a pipe opened with MODE, or #f if the lsh client could
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not be started."
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(define (shell-quote str)
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;; Sort-of shell-quote STR so it can be passed as an argument to the
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;; shell.
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(with-output-to-string
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(lambda ()
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(write str))))
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;; Let the child inherit ERROR-PORT.
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(with-error-to-port error-port
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(apply open-pipe* mode %lshg-command
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"-l" (build-machine-user machine)
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"-p" (number->string (build-machine-port machine))
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;; XXX: Remove '-i' when %LSHG-COMMAND really is lshg.
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"-i" (build-machine-private-key machine)
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(append (build-machine-ssh-options machine)
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(list (build-machine-name machine))
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(if quote?
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(map shell-quote command)
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command)))))
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;;;
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;;; Synchronization.
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;;;
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(define (lock-file file)
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"Wait and acquire an exclusive lock on FILE. Return an open port."
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(mkdir-p (dirname file))
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(let ((port (open-file file "w0")))
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(fcntl-flock port 'write-lock)
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port))
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(define (unlock-file lock)
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"Unlock LOCK."
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(fcntl-flock lock 'unlock)
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(close-port lock)
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#t)
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(define-syntax-rule (with-file-lock file exp ...)
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"Wait to acquire a lock on FILE and evaluate EXP in that context."
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(let ((port (lock-file file)))
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(dynamic-wind
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(lambda ()
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#t)
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(lambda ()
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exp ...)
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(lambda ()
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(unlock-file port)))))
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(define-syntax-rule (with-machine-lock machine hint exp ...)
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"Wait to acquire MACHINE's exclusive lock for HINT, and evaluate EXP in that
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context."
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(with-file-lock (machine-lock-file machine hint)
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exp ...))
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(define (machine-slot-file machine slot)
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"Return the file name of MACHINE's file for SLOT."
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;; For each machine we have a bunch of files representing each build slot.
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;; When choosing a build machine, we attempt to get an exclusive lock on one
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;; of these; if we fail, that means all the build slots are already taken.
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;; Inspired by Nix's build-remote.pl.
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(string-append (string-append %state-directory "/offload/"
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(build-machine-name machine)
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"/" (number->string slot))))
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(define (acquire-build-slot machine)
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"Attempt to acquire a build slot on MACHINE. Return the port representing
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the slot, or #f if none is available.
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This mechanism allows us to set a hard limit on the number of simultaneous
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connections allowed to MACHINE."
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(mkdir-p (dirname (machine-slot-file machine 0)))
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(with-machine-lock machine 'slots
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(any (lambda (slot)
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(let ((port (open-file (machine-slot-file machine slot)
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"w0")))
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(catch 'flock-error
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(lambda ()
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(fcntl-flock port 'write-lock #:wait? #f)
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;; Got it!
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(format (current-error-port)
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"process ~a acquired build slot '~a'~%"
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(getpid) (port-filename port))
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port)
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(lambda args
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;; PORT is already locked by another process.
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(close-port port)
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#f))))
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(iota (build-machine-parallel-builds machine)))))
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(define (release-build-slot slot)
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"Release SLOT, a build slot as returned as by 'acquire-build-slot'."
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(close-port slot))
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;;;
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;;; Offloading.
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;;;
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(define (build-log-port)
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"Return the default port where build logs should be sent. The default is
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file descriptor 4, which is open by the daemon before running the offload
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hook."
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(let ((port (fdopen 4 "w0")))
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;; Make sure file descriptor 4 isn't closed when PORT is GC'd.
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(set-port-revealed! port 1)
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port))
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(define %gc-root-file
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;; File name of the temporary GC root we install.
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(format #f "offload-~a-~a" (gethostname) (getpid)))
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(define (register-gc-root file machine)
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"Mark FILE, a store item, as a garbage collector root on MACHINE."
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(define script
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`(begin
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(use-modules (guix config))
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;; Note: we can't use 'add-indirect-root' because dangling links under
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;; gcroots/auto are automatically deleted by the GC. This strategy
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;; doesn't have this problem, but it requires write access to that
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;; directory.
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(let ((root-directory (string-append %state-directory
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"/gcroots/tmp")))
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(catch 'system-error
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(lambda ()
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(mkdir root-directory))
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(lambda args
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(unless (= EEXIST (system-error-errno args))
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(error "failed to create remote GC root directory"
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root-directory (system-error-errno args)))))
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(catch 'system-error
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(lambda ()
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(symlink ,file
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(string-append root-directory "/" ,%gc-root-file)))
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(lambda args
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;; If FILE already exists, we can assume that either it's a stale
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;; reference (which is fine), or another process is already
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;; building the derivation represented by FILE (which is fine
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;; too.) Thus, do nothing in that case.
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(unless (= EEXIST (system-error-errno args))
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(apply throw args)))))))
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(let ((pipe (remote-pipe machine OPEN_READ
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`("guile" "-c" ,(object->string script)))))
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(get-string-all pipe)
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(let ((status (close-pipe pipe)))
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(unless (zero? status)
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;; Better be safe than sorry: if we ignore the error here, then FILE
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;; may be GC'd just before we start using it.
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(leave (_ "failed to register GC root for '~a' on '~a' (status: ~a)~%")
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file (build-machine-name machine) status)))))
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(define (remove-gc-roots machine)
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"Remove from MACHINE the GC roots previously installed with
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'register-gc-root'."
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(define script
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`(begin
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(use-modules (guix config) (ice-9 ftw)
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(srfi srfi-1) (srfi srfi-26))
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(let ((root-directory (string-append %state-directory
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"/gcroots/tmp")))
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(false-if-exception
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(delete-file
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(string-append root-directory "/" ,%gc-root-file)))
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;; These ones were created with 'guix build -r' (there can be more
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;; than one in case of multiple-output derivations.)
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(let ((roots (filter (cut string-prefix? ,%gc-root-file <>)
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(scandir "."))))
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(for-each (lambda (file)
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(false-if-exception (delete-file file)))
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roots)))))
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(let ((pipe (remote-pipe machine OPEN_READ
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`("guile" "-c" ,(object->string script)))))
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(get-string-all pipe)
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(close-pipe pipe)))
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(define* (offload drv machine
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#:key print-build-trace? (max-silent-time 3600)
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build-timeout (log-port (build-log-port)))
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"Perform DRV on MACHINE, assuming DRV and its prerequisites are available
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there, and write the build log to LOG-PORT. Return the exit status."
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(format (current-error-port) "offloading '~a' to '~a'...~%"
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(derivation-file-name drv) (build-machine-name machine))
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(format (current-error-port) "@ build-remote ~a ~a~%"
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(derivation-file-name drv) (build-machine-name machine))
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;; Normally DRV has already been protected from GC when it was transferred.
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;; The '-r' flag below prevents the build result from being GC'd.
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(let ((pipe (remote-pipe machine OPEN_READ
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`("guix" "build"
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"-r" ,%gc-root-file
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,(format #f "--max-silent-time=~a"
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max-silent-time)
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,@(if build-timeout
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(list (format #f "--timeout=~a"
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build-timeout))
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'())
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,(derivation-file-name drv))
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;; Since 'guix build' writes the build log to its
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;; stderr, everything will go directly to LOG-PORT.
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#:error-port log-port)))
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(let loop ((line (read-line pipe)))
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(unless (eof-object? line)
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(display line log-port)
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(newline log-port)
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(loop (read-line pipe))))
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(close-pipe pipe)))
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(define* (transfer-and-offload drv machine
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#:key
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(inputs '())
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(outputs '())
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(max-silent-time 3600)
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build-timeout
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print-build-trace?)
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"Offload DRV to MACHINE. Prior to the actual offloading, transfer all of
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INPUTS to MACHINE; if building DRV succeeds, retrieve all of OUTPUTS from
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MACHINE."
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(when (begin
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(register-gc-root (derivation-file-name drv) machine)
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(send-files (cons (derivation-file-name drv) inputs)
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machine))
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(let ((status (offload drv machine
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#:print-build-trace? print-build-trace?
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#:max-silent-time max-silent-time
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#:build-timeout build-timeout)))
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(if (zero? status)
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(begin
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(retrieve-files outputs machine)
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(remove-gc-roots machine)
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(format (current-error-port)
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"done with offloaded '~a'~%"
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(derivation-file-name drv)))
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(begin
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(remove-gc-roots machine)
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(format (current-error-port)
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"derivation '~a' offloaded to '~a' failed \
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with exit code ~a~%"
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(derivation-file-name drv)
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(build-machine-name machine)
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(status:exit-val status))
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;; Use exit code 100 for a permanent build failure. The daemon
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;; interprets other non-zero codes as transient build failures.
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(primitive-exit 100))))))
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(define (send-files files machine)
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"Send the subset of FILES that's missing to MACHINE's store. Return #t on
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success, #f otherwise."
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(define (missing-files files)
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;; Return the subset of FILES not already on MACHINE.
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(let*-values (((files)
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(format #f "~{~a~%~}" files))
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((missing pids)
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(filtered-port
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(append (list (which %lshg-command)
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"-l" (build-machine-user machine)
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"-p" (number->string
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(build-machine-port machine))
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"-i" (build-machine-private-key machine))
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(build-machine-ssh-options machine)
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(cons (build-machine-name machine)
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'("guix" "archive" "--missing")))
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(open-input-string files)))
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((result)
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(get-string-all missing)))
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(for-each waitpid pids)
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(string-tokenize result)))
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(with-store store
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(guard (c ((nix-protocol-error? c)
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(warning (_ "failed to export files for '~a': ~s~%")
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(build-machine-name machine)
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c)
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#f))
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;; Compute the subset of FILES missing on MACHINE, and send them in
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;; topologically sorted order so that they can actually be imported.
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;;
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;; To reduce load on the machine that's offloading (since it's typically
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;; already quite busy, see hydra.gnu.org), compress with gzip rather
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;; than xz: For a compression ratio 2 times larger, it is 20 times
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;; faster.
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(let* ((files (missing-files (topologically-sorted store files)))
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(pipe (remote-pipe machine OPEN_WRITE
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'("gzip" "-dc" "|"
|
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"guix" "archive" "--import")
|
||
#:quote? #f)))
|
||
(format #t (_ "sending ~a store files to '~a'...~%")
|
||
(length files) (build-machine-name machine))
|
||
(call-with-compressed-output-port 'gzip pipe
|
||
(lambda (compressed)
|
||
(catch 'system-error
|
||
(lambda ()
|
||
(export-paths store files compressed))
|
||
(lambda args
|
||
(warning (_ "failed while exporting files to '~a': ~a~%")
|
||
(build-machine-name machine)
|
||
(strerror (system-error-errno args))))))
|
||
#:options '("--fast"))
|
||
|
||
;; Wait for the 'lsh' process to complete.
|
||
(zero? (close-pipe pipe))))))
|
||
|
||
(define (retrieve-files files machine)
|
||
"Retrieve FILES from MACHINE's store, and import them."
|
||
(define host
|
||
(build-machine-name machine))
|
||
|
||
(let ((pipe (remote-pipe machine OPEN_READ
|
||
`("guix" "archive" "--export" ,@files
|
||
"|" "xz" "-c")
|
||
#:quote? #f)))
|
||
(and pipe
|
||
(with-store store
|
||
(guard (c ((nix-protocol-error? c)
|
||
(warning (_ "failed to import files from '~a': ~s~%")
|
||
host c)
|
||
#f))
|
||
(format (current-error-port) "retrieving ~a files from '~a'...~%"
|
||
(length files) host)
|
||
|
||
;; We cannot use the 'import-paths' RPC here because we already
|
||
;; hold the locks for FILES.
|
||
(call-with-decompressed-port 'xz pipe
|
||
(lambda (decompressed)
|
||
(restore-file-set decompressed
|
||
#:log-port (current-error-port)
|
||
#:lock? #f)))
|
||
|
||
;; Wait for the 'lsh' process to complete.
|
||
(zero? (close-pipe pipe)))))))
|
||
|
||
|
||
;;;
|
||
;;; Scheduling.
|
||
;;;
|
||
|
||
(define (machine-matches? machine requirements)
|
||
"Return #t if MACHINE matches REQUIREMENTS."
|
||
(and (string=? (build-requirements-system requirements)
|
||
(build-machine-system machine))
|
||
(lset<= string=?
|
||
(build-requirements-features requirements)
|
||
(build-machine-features machine))))
|
||
|
||
(define (machine-load machine)
|
||
"Return the load of MACHINE, divided by the number of parallel builds
|
||
allowed on MACHINE."
|
||
(let* ((pipe (remote-pipe machine OPEN_READ `("cat" "/proc/loadavg")))
|
||
(line (read-line pipe))
|
||
(status (close-pipe pipe)))
|
||
(unless (eqv? 0 (status:exit-val status))
|
||
(warning (_ "failed to obtain load of '~a': SSH client exited with ~a~%")
|
||
(build-machine-name machine)
|
||
(status:exit-val status)))
|
||
|
||
(if (eof-object? line)
|
||
+inf.0 ;MACHINE does not respond, so assume it is infinitely loaded
|
||
(match (string-tokenize line)
|
||
((one five fifteen . _)
|
||
(let* ((raw (string->number five))
|
||
(jobs (build-machine-parallel-builds machine))
|
||
(normalized (/ raw jobs)))
|
||
(format (current-error-port) "load on machine '~a' is ~s\
|
||
(normalized: ~s)~%"
|
||
(build-machine-name machine) raw normalized)
|
||
normalized))
|
||
(_
|
||
+inf.0))))) ;something's fishy about MACHINE, so avoid it
|
||
|
||
(define (machine-power-factor m)
|
||
"Return a factor that aggregates the speed and load of M. The higher the
|
||
better."
|
||
(/ (build-machine-speed m)
|
||
(+ 1 (machine-load m))))
|
||
|
||
(define (machine-less-loaded-or-faster? m1 m2)
|
||
"Return #t if M1 is either less loaded or faster than M2. (This relation
|
||
defines a total order on machines.)"
|
||
(> (machine-power-factor m1) (machine-power-factor m2)))
|
||
|
||
(define (machine-lock-file machine hint)
|
||
"Return the name of MACHINE's lock file for HINT."
|
||
(string-append %state-directory "/offload/"
|
||
(build-machine-name machine)
|
||
"." (symbol->string hint) ".lock"))
|
||
|
||
(define (machine-choice-lock-file)
|
||
"Return the name of the file used as a lock when choosing a build machine."
|
||
(string-append %state-directory "/offload/machine-choice.lock"))
|
||
|
||
|
||
(define %slots
|
||
;; List of acquired build slots (open ports).
|
||
'())
|
||
|
||
(define (choose-build-machine machines)
|
||
"Return the best machine among MACHINES, or #f."
|
||
|
||
;; Proceed like this:
|
||
;; 1. Acquire the global machine-choice lock.
|
||
;; 2. For all MACHINES, attempt to acquire a build slot, and filter out
|
||
;; those machines for which we failed.
|
||
;; 3. Choose the best machine among those that are left.
|
||
;; 4. Release the previously-acquired build slots of the other machines.
|
||
;; 5. Release the global machine-choice lock.
|
||
|
||
(with-file-lock (machine-choice-lock-file)
|
||
(define machines+slots
|
||
(filter-map (lambda (machine)
|
||
(let ((slot (acquire-build-slot machine)))
|
||
(and slot (list machine slot))))
|
||
machines))
|
||
|
||
(define (undecorate pred)
|
||
(lambda (a b)
|
||
(match a
|
||
((machine1 slot1)
|
||
(match b
|
||
((machine2 slot2)
|
||
(pred machine1 machine2)))))))
|
||
|
||
(let loop ((machines+slots
|
||
(sort machines+slots
|
||
(undecorate machine-less-loaded-or-faster?))))
|
||
(match machines+slots
|
||
(((best slot) others ...)
|
||
;; Return the best machine unless it's already overloaded.
|
||
(if (< (machine-load best) 2.)
|
||
(match others
|
||
(((machines slots) ...)
|
||
;; Release slots from the uninteresting machines.
|
||
(for-each release-build-slot slots)
|
||
|
||
;; Prevent SLOT from being GC'd.
|
||
(set! %slots (cons slot %slots))
|
||
best))
|
||
(begin
|
||
;; BEST is overloaded, so try the next one.
|
||
(release-build-slot slot)
|
||
(loop others))))
|
||
(() #f)))))
|
||
|
||
(define* (process-request wants-local? system drv features
|
||
#:key
|
||
print-build-trace? (max-silent-time 3600)
|
||
build-timeout)
|
||
"Process a request to build DRV."
|
||
(let* ((local? (and wants-local? (string=? system (%current-system))))
|
||
(reqs (build-requirements
|
||
(system system)
|
||
(features features)))
|
||
(candidates (filter (cut machine-matches? <> reqs)
|
||
(build-machines))))
|
||
(match candidates
|
||
(()
|
||
;; We'll never be able to match REQS.
|
||
(display "# decline\n"))
|
||
((_ ...)
|
||
(let ((machine (choose-build-machine candidates)))
|
||
(if machine
|
||
(begin
|
||
;; Offload DRV to MACHINE.
|
||
(display "# accept\n")
|
||
(let ((inputs (string-tokenize (read-line)))
|
||
(outputs (string-tokenize (read-line))))
|
||
(transfer-and-offload drv machine
|
||
#:inputs inputs
|
||
#:outputs outputs
|
||
#:max-silent-time max-silent-time
|
||
#:build-timeout build-timeout
|
||
#:print-build-trace? print-build-trace?)))
|
||
|
||
;; Not now, all the machines are busy.
|
||
(display "# postpone\n")))))))
|
||
|
||
(define-syntax-rule (with-nar-error-handling body ...)
|
||
"Execute BODY with any &nar-error suitably reported to the user."
|
||
(guard (c ((nar-error? c)
|
||
(let ((file (nar-error-file c)))
|
||
(if (condition-has-type? c &message)
|
||
(leave (_ "while importing file '~a': ~a~%")
|
||
file (gettext (condition-message c)))
|
||
(leave (_ "failed to import file '~a'~%")
|
||
file)))))
|
||
body ...))
|
||
|
||
|
||
;;;
|
||
;;; Entry point.
|
||
;;;
|
||
|
||
(define (guix-offload . args)
|
||
(define request-line-rx
|
||
;; The request format. See 'tryBuildHook' method in build.cc.
|
||
(make-regexp "([01]) ([a-z0-9_-]+) (/[[:graph:]]+.drv) ([[:graph:]]*)"))
|
||
|
||
(define not-coma
|
||
(char-set-complement (char-set #\,)))
|
||
|
||
;; Make sure $HOME really corresponds to the current user. This is
|
||
;; necessary since lsh uses that to determine the location of the yarrow
|
||
;; seed file, and fails if it's owned by someone else.
|
||
(and=> (passwd:dir (getpw (getuid)))
|
||
(cut setenv "HOME" <>))
|
||
|
||
(match args
|
||
((system max-silent-time print-build-trace? build-timeout)
|
||
(let ((max-silent-time (string->number max-silent-time))
|
||
(build-timeout (string->number build-timeout))
|
||
(print-build-trace? (string=? print-build-trace? "1")))
|
||
(parameterize ((%current-system system))
|
||
(let loop ((line (read-line)))
|
||
(unless (eof-object? line)
|
||
(cond ((regexp-exec request-line-rx line)
|
||
=>
|
||
(lambda (match)
|
||
(with-nar-error-handling
|
||
(process-request (equal? (match:substring match 1) "1")
|
||
(match:substring match 2) ; system
|
||
(call-with-input-file
|
||
(match:substring match 3)
|
||
read-derivation)
|
||
(string-tokenize
|
||
(match:substring match 4) not-coma)
|
||
#:print-build-trace? print-build-trace?
|
||
#:max-silent-time max-silent-time
|
||
#:build-timeout build-timeout))))
|
||
(else
|
||
(leave (_ "invalid request line: ~s~%") line)))
|
||
(loop (read-line)))))))
|
||
(("--version")
|
||
(show-version-and-exit "guix offload"))
|
||
(("--help")
|
||
(format #t (_ "Usage: guix offload SYSTEM PRINT-BUILD-TRACE
|
||
Process build offload requests written on the standard input, possibly
|
||
offloading builds to the machines listed in '~a'.~%")
|
||
%machine-file)
|
||
(display (_ "
|
||
This tool is meant to be used internally by 'guix-daemon'.\n"))
|
||
(show-bug-report-information))
|
||
(x
|
||
(leave (_ "invalid arguments: ~{~s ~}~%") x))))
|
||
|
||
;;; Local Variables:
|
||
;;; eval: (put 'with-machine-lock 'scheme-indent-function 2)
|
||
;;; eval: (put 'with-file-lock 'scheme-indent-function 1)
|
||
;;; eval: (put 'with-error-to-port 'scheme-indent-function 1)
|
||
;;; End:
|
||
|
||
;;; offload.scm ends here
|