summaryrefslogtreecommitdiff
path: root/doc
diff options
context:
space:
mode:
authorMarius Bakke <mbakke@fastmail.com>2019-07-12 01:03:53 +0200
committerMarius Bakke <mbakke@fastmail.com>2019-07-12 01:03:53 +0200
commitfb9a23a3f3ad3d7b5b7f03b2007baf27684d6bbd (patch)
treeafbd3f4f33771c61254b0c3d977092542fbe8009 /doc
parent1c4b72cb34640638e40c5190676e5c8c352d292d (diff)
parent5a836ce38c9c29e9c2bd306007347486b90c5064 (diff)
Merge branch 'master' into core-updates
Conflicts: gnu/local.mk gnu/packages/python-xyz.scm gnu/packages/xml.scm guix/gexp.scm po/guix/POTFILES.in
Diffstat (limited to 'doc')
-rw-r--r--doc/build.scm563
-rw-r--r--doc/guix.texi122
2 files changed, 685 insertions, 0 deletions
diff --git a/doc/build.scm b/doc/build.scm
new file mode 100644
index 0000000000..e628a91048
--- /dev/null
+++ b/doc/build.scm
@@ -0,0 +1,563 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 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/>.
+
+
+;; This file contains machinery to build HTML and PDF copies of the manual
+;; that can be readily published on the web site. To do that, run:
+;;
+;; guix build -f build.scm
+;;
+;; The result is a directory hierarchy that can be used as the manual/
+;; sub-directory of the web site.
+
+(use-modules (guix)
+ (guix gexp)
+ (guix git)
+ (guix git-download)
+ (git)
+ (gnu packages base)
+ (gnu packages gawk)
+ (gnu packages gettext)
+ (gnu packages guile)
+ (gnu packages texinfo)
+ (gnu packages tex)
+ (srfi srfi-19)
+ (srfi srfi-71))
+
+(define file-append*
+ (@@ (guix self) file-append*))
+
+(define translated-texi-manuals
+ (@@ (guix self) translate-texi-manuals))
+
+(define info-manual
+ (@@ (guix self) info-manual))
+
+(define %languages
+ '("de" "en" "es" "fr" "ru" "zh_CN"))
+
+(define (texinfo-manual-images source)
+ "Return a directory containing all the images used by the user manual, taken
+from SOURCE, the root of the source tree."
+ (define graphviz
+ (module-ref (resolve-interface '(gnu packages graphviz))
+ 'graphviz))
+
+ (define images
+ (file-append* source "doc/images"))
+
+ (define build
+ (with-imported-modules '((guix build utils))
+ #~(begin
+ (use-modules (guix build utils)
+ (srfi srfi-26))
+
+ (define (dot->image dot-file format)
+ (invoke #+(file-append graphviz "/bin/dot")
+ "-T" format "-Gratio=.9" "-Gnodesep=.005"
+ "-Granksep=.00005" "-Nfontsize=9"
+ "-Nheight=.1" "-Nwidth=.1"
+ "-o" (string-append #$output "/"
+ (basename dot-file ".dot")
+ "." format)
+ dot-file))
+
+ ;; Build graphs.
+ (mkdir-p #$output)
+ (for-each (lambda (dot-file)
+ (for-each (cut dot->image dot-file <>)
+ '("png" "pdf")))
+ (find-files #$images "\\.dot$"))
+
+ ;; Copy other PNGs.
+ (for-each (lambda (png-file)
+ (install-file png-file #$output))
+ (find-files #$images "\\.png$")))))
+
+ (computed-file "texinfo-manual-images" build))
+
+(define* (texinfo-manual-source source #:key
+ (version "0.0")
+ (languages %languages)
+ (date 1))
+ "Gather all the source files of the Texinfo manuals from SOURCE--.texi file
+as well as images, OS examples, and translations."
+ (define documentation
+ (file-append* source "doc"))
+
+ (define examples
+ (file-append* source "gnu/system/examples"))
+
+ (define build
+ (with-imported-modules '((guix build utils))
+ #~(begin
+ (use-modules (guix build utils)
+ (srfi srfi-19))
+
+ (define (make-version-texi language)
+ ;; Create the 'version.texi' file for LANGUAGE.
+ (let ((file (if (string=? language "en")
+ "version.texi"
+ (string-append "version-" language ".texi"))))
+ (call-with-output-file (string-append #$output "/" file)
+ (lambda (port)
+ (let* ((version #$version)
+ (time (make-time time-utc 0 #$date))
+ (date (time-utc->date time)))
+ (format port "
+@set UPDATED ~a
+@set UPDATED-MONTH ~a
+@set EDITION ~a
+@set VERSION ~a\n"
+ (date->string date "~e ~B ~Y")
+ (date->string date "~B ~Y")
+ version version))))))
+
+ (install-file #$(file-append* documentation "/htmlxref.cnf")
+ #$output)
+
+ (for-each (lambda (texi)
+ (install-file texi #$output))
+ (append (find-files #$documentation "\\.(texi|scm)$")
+ (find-files #$(translated-texi-manuals source)
+ "\\.texi$")))
+
+ ;; Create 'version.texi'.
+ (for-each make-version-texi '#$languages)
+
+ ;; Copy configuration templates that the manual includes.
+ (for-each (lambda (template)
+ (copy-file template
+ (string-append
+ #$output "/os-config-"
+ (basename template ".tmpl")
+ ".texi")))
+ (find-files #$examples "\\.tmpl$"))
+
+ (symlink #$(texinfo-manual-images source)
+ (string-append #$output "/images")))))
+
+ (computed-file "texinfo-manual-source" build))
+
+(define %web-site-url
+ ;; URL of the web site home page.
+ (or (getenv "GUIX_WEB_SITE_URL")
+ "/software/guix/"))
+
+(define %makeinfo-html-options
+ ;; Options passed to 'makeinfo --html'.
+ '("--css-ref=https://www.gnu.org/software/gnulib/manual.css"))
+
+(define* (html-manual source #:key (languages %languages)
+ (version "0.0")
+ (manual "guix")
+ (date 1)
+ (options %makeinfo-html-options))
+ "Return the HTML manuals built from SOURCE for all LANGUAGES, with the given
+makeinfo OPTIONS."
+ (define manual-source
+ (texinfo-manual-source source
+ #:version version
+ #:languages languages
+ #:date date))
+
+ (define build
+ (with-imported-modules '((guix build utils))
+ #~(begin
+ (use-modules (guix build utils)
+ (ice-9 match))
+
+ (define (normalize language)
+ ;; Normalize LANGUAGE. For instance, "zh_CN" become "zh-cn".
+ (string-map (match-lambda
+ (#\_ #\-)
+ (chr chr))
+ (string-downcase language)))
+
+ ;; Install a UTF-8 locale so that 'makeinfo' is at ease.
+ (setenv "GUIX_LOCPATH"
+ #+(file-append glibc-utf8-locales "/lib/locale"))
+ (setenv "LC_ALL" "en_US.utf8")
+
+ (setvbuf (current-output-port) 'line)
+ (setvbuf (current-error-port) 'line)
+
+ (for-each (lambda (language)
+ (let ((opts `("--html"
+ "-c" ,(string-append "TOP_NODE_UP_URL=/manual/"
+ language)
+ #$@options
+ ,(if (string=? language "en")
+ (string-append #$manual-source "/"
+ #$manual ".texi")
+ (string-append #$manual-source "/"
+ #$manual "." language ".texi")))))
+ (format #t "building HTML manual for language '~a'...~%"
+ language)
+ (mkdir-p (string-append #$output "/"
+ (normalize language)))
+ (setenv "LANGUAGE" language)
+ (apply invoke #$(file-append texinfo "/bin/makeinfo")
+ "-o" (string-append #$output "/"
+ (normalize language)
+ "/html_node")
+ opts)
+ (apply invoke #$(file-append texinfo "/bin/makeinfo")
+ "--no-split"
+ "-o"
+ (string-append #$output "/"
+ (normalize language)
+ "/" #$manual
+ (if (string=? language "en")
+ ""
+ (string-append "." language))
+ ".html")
+ opts)))
+ '#$languages))))
+
+ (computed-file (string-append manual "-html-manual") build))
+
+(define* (pdf-manual source #:key (languages %languages)
+ (version "0.0")
+ (manual "guix")
+ (date 1)
+ (options '()))
+ "Return the HTML manuals built from SOURCE for all LANGUAGES, with the given
+makeinfo OPTIONS."
+ (define manual-source
+ (texinfo-manual-source source
+ #:version version
+ #:languages languages
+ #:date date))
+
+ ;; FIXME: This union works, except for the table of contents of non-English
+ ;; manuals, which contains escape sequences like "^^ca^^fe" instead of
+ ;; accented letters.
+ ;;
+ ;; (define texlive
+ ;; (texlive-union (list texlive-tex-texinfo
+ ;; texlive-generic-epsf
+ ;; texlive-fonts-ec)))
+
+ (define build
+ (with-imported-modules '((guix build utils))
+ #~(begin
+ (use-modules (guix build utils)
+ (srfi srfi-34)
+ (ice-9 match))
+
+ (define (normalize language) ;XXX: deduplicate
+ ;; Normalize LANGUAGE. For instance, "zh_CN" becomes "zh-cn".
+ (string-map (match-lambda
+ (#\_ #\-)
+ (chr chr))
+ (string-downcase language)))
+
+ ;; Install a UTF-8 locale so that 'makeinfo' is at ease.
+ (setenv "GUIX_LOCPATH"
+ #+(file-append glibc-utf8-locales "/lib/locale"))
+ (setenv "LC_ALL" "en_US.utf8")
+ (setenv "PATH"
+ (string-append #+(file-append texlive "/bin") ":"
+ #+(file-append texinfo "/bin") ":"
+
+ ;; Below are command-line tools needed by
+ ;; 'texi2dvi' and friends.
+ #+(file-append sed "/bin") ":"
+ #+(file-append grep "/bin") ":"
+ #+(file-append coreutils "/bin") ":"
+ #+(file-append gawk "/bin") ":"
+ #+(file-append tar "/bin") ":"
+ #+(file-append diffutils "/bin")))
+
+ (setvbuf (current-output-port) 'line)
+ (setvbuf (current-error-port) 'line)
+
+ (setenv "HOME" (getcwd)) ;for kpathsea/mktextfm
+
+ ;; 'SOURCE_DATE_EPOCH' is honored by pdftex.
+ (setenv "SOURCE_DATE_EPOCH" "1")
+
+ (for-each (lambda (language)
+ (let ((opts `("--pdf"
+ "-I" "."
+ #$@options
+ ,(if (string=? language "en")
+ (string-append #$manual-source "/"
+ #$manual ".texi")
+ (string-append #$manual-source "/"
+ #$manual "." language ".texi")))))
+ (format #t "building PDF manual for language '~a'...~%"
+ language)
+ (mkdir-p (string-append #$output "/"
+ (normalize language)))
+ (setenv "LANGUAGE" language)
+
+
+ ;; FIXME: Unfortunately building PDFs for non-Latin
+ ;; alphabets doesn't work:
+ ;; <https://lists.gnu.org/archive/html/help-texinfo/2012-01/msg00014.html>.
+ (guard (c ((invoke-error? c)
+ (format (current-error-port)
+ "~%~%Failed to produce \
+PDF for language '~a'!~%~%"
+ language)))
+ (apply invoke #$(file-append texinfo "/bin/makeinfo")
+ "--pdf" "-o"
+ (string-append #$output "/"
+ (normalize language)
+ "/" #$manual
+ (if (string=? language "en")
+ ""
+ (string-append "."
+ language))
+ ".pdf")
+ opts))))
+ '#$languages))))
+
+ (computed-file (string-append manual "-pdf-manual") build))
+
+(define (guix-manual-text-domain source languages)
+ "Return the PO files for LANGUAGES of the 'guix-manual' text domain taken
+from SOURCE."
+ (define po-directory
+ (file-append* source "/po/doc"))
+
+ (define build
+ (with-imported-modules '((guix build utils))
+ #~(begin
+ (use-modules (guix build utils))
+
+ (mkdir-p #$output)
+ (for-each (lambda (language)
+ (define directory
+ (string-append #$output "/" language
+ "/LC_MESSAGES"))
+
+ (mkdir-p directory)
+ (invoke #+(file-append gnu-gettext "/bin/msgfmt")
+ "-c" "-o"
+ (string-append directory "/guix-manual.mo")
+ (string-append #$po-directory "/guix-manual."
+ language ".po")))
+ '#$(delete "en" languages)))))
+
+ (computed-file "guix-manual-po" build))
+
+(define* (html-manual-indexes source
+ #:key (languages %languages)
+ (version "0.0")
+ (manual "guix")
+ (date 1))
+ (define build
+ (with-imported-modules '((guix build utils))
+ #~(begin
+ (use-modules (guix build utils)
+ (ice-9 match)
+ (ice-9 popen)
+ (sxml simple)
+ (srfi srfi-19))
+
+ (define (normalize language) ;XXX: deduplicate
+ ;; Normalize LANGUAGE. For instance, "zh_CN" become "zh-cn".
+ (string-map (match-lambda
+ (#\_ #\-)
+ (chr chr))
+ (string-downcase language)))
+
+ (define-syntax-rule (with-language language exp ...)
+ (let ((lang (getenv "LANGUAGE")))
+ (dynamic-wind
+ (lambda ()
+ (setenv "LANGUAGE" language)
+ (setlocale LC_MESSAGES))
+ (lambda () exp ...)
+ (lambda ()
+ (if lang
+ (setenv "LANGUAGE" lang)
+ (unsetenv "LANGUAGE"))
+ (setlocale LC_MESSAGES)))))
+
+ ;; (put 'with-language 'scheme-indent-function 1)
+ (define* (translate str language
+ #:key (domain "guix-manual"))
+ (define exp
+ `(begin
+ (bindtextdomain "guix-manual"
+ #+(guix-manual-text-domain
+ source
+ languages))
+ (write (gettext ,str "guix-manual"))))
+
+ (with-language language
+ ;; Since the 'gettext' function caches msgid translations,
+ ;; regardless of $LANGUAGE, we have to spawn a new process each
+ ;; time we want to translate to a different language. Bah!
+ (let* ((pipe (open-pipe* OPEN_READ
+ #+(file-append guile-2.2
+ "/bin/guile")
+ "-c" (object->string exp)))
+ (str (read pipe)))
+ (close-pipe pipe)
+ str)))
+
+ (define (seconds->string seconds language)
+ (let* ((time (make-time time-utc 0 seconds))
+ (date (time-utc->date time)))
+ (with-language language (date->string date "~e ~B ~Y"))))
+
+ (define (guix-url path)
+ (string-append #$%web-site-url path))
+
+ (define (sxml-index language)
+ (define title
+ (translate "GNU Guix Reference Manual" language))
+
+ ;; FIXME: Avoid duplicating styling info from guix-artwork.git.
+ `(html (@ (lang ,language))
+ (head
+ (title ,(string-append title " — GNU Guix"))
+ (meta (@ (charset "UTF-8")))
+ (meta (@ (name "viewport") (content "width=device-width, initial-scale=1.0")))
+ ;; Menu prefetch.
+ (link (@ (rel "prefetch") (href ,(guix-url "menu/index.html"))))
+ ;; Base CSS.
+ (link (@ (rel "stylesheet") (href ,(guix-url "static/base/css/elements.css"))))
+ (link (@ (rel "stylesheet") (href ,(guix-url "static/base/css/common.css"))))
+ (link (@ (rel "stylesheet") (href ,(guix-url "static/base/css/messages.css"))))
+ (link (@ (rel "stylesheet") (href ,(guix-url "static/base/css/navbar.css"))))
+ (link (@ (rel "stylesheet") (href ,(guix-url "static/base/css/breadcrumbs.css"))))
+ (link (@ (rel "stylesheet") (href ,(guix-url "static/base/css/buttons.css"))))
+ (link (@ (rel "stylesheet") (href ,(guix-url "static/base/css/footer.css"))))
+
+ (link (@ (rel "stylesheet") (href ,(guix-url "static/base/css/page.css"))))
+ (link (@ (rel "stylesheet") (href ,(guix-url "static/base/css/post.css")))))
+ (body
+ (header (@ (class "navbar"))
+ (h1 (a (@ (class "branding")
+ (href #$%web-site-url)))
+ (span (@ (class "a11y-offset"))
+ "Guix"))
+ (nav (@ (class "menu"))))
+ (nav (@ (class "breadcrumbs"))
+ (a (@ (class "crumb")
+ (href #$%web-site-url))
+ "Home"))
+ (main
+ (article
+ (@ (class "page centered-block limit-width"))
+ (h2 ,title)
+ (p (@ (class "post-metadata centered-text"))
+ #$version " — "
+ ,(seconds->string #$date language))
+
+ (div
+ (ul
+ (li (a (@ (href "html_node"))
+ "HTML, with one page per node"))
+ (li (a (@ (href
+ ,(string-append
+ #$manual
+ (if (string=? language
+ "en")
+ ""
+ (string-append "."
+ language))
+ ".html")))
+ "HTML, entirely on one page"))
+ ,@(if (member language '("ru" "zh_CN"))
+ '()
+ `((li (a (@ (href ,(string-append
+ #$manual
+ (if (string=? language "en")
+ ""
+ (string-append "."
+ language))
+ ".pdf"))))
+ "PDF")))))))
+ (footer))))
+
+ (define (write-index language file)
+ (call-with-output-file file
+ (lambda (port)
+ (display "<!DOCTYPE html>\n" port)
+ (sxml->xml (sxml-index language) port))))
+
+ (setenv "GUIX_LOCPATH"
+ #+(file-append glibc-utf8-locales "/lib/locale"))
+ (setenv "LC_ALL" "en_US.utf8")
+ (setlocale LC_ALL "en_US.utf8")
+
+ (bindtextdomain "guix-manual"
+ #+(guix-manual-text-domain source languages))
+
+ (for-each (lambda (language)
+ (define directory
+ (string-append #$output "/"
+ (normalize language)))
+
+ (mkdir-p directory)
+ (write-index language
+ (string-append directory
+ "/index.html")))
+ '#$languages))))
+
+ (computed-file "html-indexes" build))
+
+(define* (pdf+html-manual source
+ #:key (languages %languages)
+ (version "0.0")
+ (date (time-second (current-time time-utc)))
+ (manual "guix"))
+ "Return the union of the HTML and PDF manuals, as well as the indexes."
+ (directory-union (string-append manual "-manual")
+ (map (lambda (proc)
+ (proc source
+ #:date date
+ #:languages languages
+ #:version version
+ #:manual manual))
+ (list html-manual-indexes
+ html-manual pdf-manual))
+ #:copy? #t))
+
+(define (latest-commit+date directory)
+ "Return two values: the last commit ID (a hex string) for DIRECTORY, and its
+commit date (an integer)."
+ (let* ((repository (repository-open directory))
+ (head (repository-head repository))
+ (oid (reference-target head))
+ (commit (commit-lookup repository oid)))
+ ;; TODO: Use (git describe) when it's widely available.
+ (values (oid->string oid) (commit-time commit))))
+
+
+(let* ((root (canonicalize-path
+ (string-append (current-source-directory) "/..")))
+ (commit date (latest-commit+date root)))
+ (format (current-error-port)
+ "building manual from work tree around commit ~a, ~a~%"
+ commit
+ (let* ((time (make-time time-utc 0 date))
+ (date (time-utc->date time)))
+ (date->string date "~e ~B ~Y")))
+ (pdf+html-manual (local-file root "guix" #:recursive? #t
+ #:select? (git-predicate root))
+ #:version (or (getenv "GUIX_MANUAL_VERSION")
+ (string-take commit 7))
+ #:date date))
diff --git a/doc/guix.texi b/doc/guix.texi
index 33a3fbff5a..cb2cfed637 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -65,6 +65,7 @@ Copyright @copyright{} 2018 Alex Vong@*
Copyright @copyright{} 2019 Josh Holland@*
Copyright @copyright{} 2019 Diego Nicola Barbato@*
Copyright @copyright{} 2019 Ivan Petkov@*
+Copyright @copyright{} 2019 Jakob L. Kreuze@*
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3 or
@@ -81,6 +82,7 @@ Documentation License''.
* guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
* guix pull: (guix)Invoking guix pull. Update the list of available packages.
* guix system: (guix)Invoking guix system. Manage the operating system configuration.
+* guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
@end direntry
@dircategory Software development
@@ -269,6 +271,7 @@ System Configuration
* Initial RAM Disk:: Linux-Libre bootstrapping.
* Bootloader Configuration:: Configuring the boot loader.
* Invoking guix system:: Instantiating a system configuration.
+* Invoking guix deploy:: Deploying a system configuration to a remote host.
* Running Guix in a VM:: How to run Guix System in a virtual machine.
* Defining Services:: Adding new service definitions.
@@ -4654,6 +4657,14 @@ While this will limit the leaking of user identity through home paths
and each of the user fields, this is only one useful component of a
broader privacy/anonymity solution---not one in and of itself.
+@item --no-cwd
+For containers, the default behavior is to share the current working
+directory with the isolated container and immediately change to that
+directory within the container. If this is undesirable, @code{--no-cwd}
+will cause the current working directory to @emph{not} be automatically
+shared and will change to the user's home directory within the container
+instead. See also @code{--user}.
+
@item --expose=@var{source}[=@var{target}]
For containers, expose the file system @var{source} from the host system
as the read-only file system @var{target} within the container. If
@@ -10296,6 +10307,7 @@ instance to support new system services.
* Initial RAM Disk:: Linux-Libre bootstrapping.
* Bootloader Configuration:: Configuring the boot loader.
* Invoking guix system:: Instantiating a system configuration.
+* Invoking guix deploy:: Deploying a system configuration to a remote host.
* Running Guix in a VM:: How to run Guix System in a virtual machine.
* Defining Services:: Adding new service definitions.
@end menu
@@ -25392,6 +25404,116 @@ example graph.
@end table
+@node Invoking guix deploy
+@section Invoking @code{guix deploy}
+
+We've already seen @code{operating-system} declarations used to manage a
+machine's configuration locally. Suppose you need to configure multiple
+machines, though---perhaps you're managing a service on the web that's
+comprised of several servers. @command{guix deploy} enables you to use those
+same @code{operating-system} declarations to manage multiple remote hosts at
+once as a logical ``deployment''.
+
+@quotation Note
+The functionality described in this section is still under development
+and is subject to change. Get in touch with us on
+@email{guix-devel@@gnu.org}!
+@end quotation
+
+@example
+guix deploy @var{file}
+@end example
+
+Such an invocation will deploy the machines that the code within @var{file}
+evaluates to. As an example, @var{file} might contain a definition like this:
+
+@example
+;; This is a Guix deployment of a "bare bones" setup, with
+;; no X11 display server, to a machine with an SSH daemon
+;; listening on localhost:2222. A configuration such as this
+;; may be appropriate for virtual machine with ports
+;; forwarded to the host's loopback interface.
+
+(use-service-modules networking ssh)
+(use-package-modules bootloaders)
+
+(define %system
+ (operating-system
+ (host-name "gnu-deployed")
+ (timezone "Etc/UTC")
+ (bootloader (bootloader-configuration
+ (bootloader grub-bootloader)
+ (target "/dev/vda")
+ (terminal-outputs '(console))))
+ (file-systems (cons (file-system
+ (mount-point "/")
+ (device "/dev/vda1")
+ (type "ext4"))
+ %base-file-systems))
+ (services
+ (append (list (service dhcp-client-service-type)
+ (service openssh-service-type
+ (openssh-configuration
+ (permit-root-login #t)
+ (allow-empty-passwords? #t))))
+ %base-services))))
+
+(list (machine
+ (system %system)
+ (environment managed-host-environment-type)
+ (configuration (machine-ssh-configuration
+ (host-name "localhost")
+ (identity "./id_rsa")
+ (port 2222)))))
+@end example
+
+The file should evaluate to a list of @var{machine} objects. This example,
+upon being deployed, will create a new generation on the remote system
+realizing the @code{operating-system} declaration @var{%system}.
+@var{environment} and @var{configuration} specify how the machine should be
+provisioned---that is, how the computing resources should be created and
+managed. The above example does not create any resources, as a
+@code{'managed-host} is a machine that is already running the Guix system and
+available over the network. This is a particularly simple case; a more
+complex deployment may involve, for example, starting virtual machines through
+a Virtual Private Server (VPS) provider. In such a case, a different
+@var{environment} type would be used.
+
+@deftp {Data Type} machine
+This is the data type representing a single machine in a heterogeneous Guix
+deployment.
+
+@table @asis
+@item @code{system}
+The object of the operating system configuration to deploy.
+
+@item @code{environment}
+An @code{environment-type} describing how the machine should be provisioned.
+At the moment, the only supported value is
+@code{managed-host-environment-type}.
+
+@item @code{configuration} (default: @code{#f})
+An object describing the configuration for the machine's @code{environment}.
+If the @code{environment} has a default configuration, @code{#f} maybe used.
+If @code{#f} is used for an environment with no default configuration,
+however, an error will be thrown.
+@end table
+@end deftp
+
+@deftp {Data Type} machine-ssh-configuration
+This is the data type representing the SSH client parameters for a machine
+with an @code{environment} of @code{managed-host-environment-type}.
+
+@table @asis
+@item @code{host-name}
+@item @code{port} (default: @code{22})
+@item @code{user} (default: @code{"root"})
+@item @code{identity} (default: @code{#f})
+If specified, the path to the SSH private key to use to authenticate with the
+remote host.
+@end table
+@end deftp
+
@node Running Guix in a VM
@section Running Guix in a Virtual Machine