[bug#60735,v2,2/3] system: Deprecate hosts-file.
Commit Message
* gnu/system.scm (operating-system-hosts-file): Deprecate procedure.
(warn-hosts-file-field-deprecation): New procedure, helper for
deprecated variable).
(operating-system)[hosts-file]: Use helper to warn deprecated field.
(operating-system-default-essential-services)
(hurd-default-essential-services): Use hosts-service-type.
(local-host-aliases): Return a list of host-entry records.
(default-/etc/hosts): Remove procedure.
(operating-system-etc-service): Remove hosts file.
* doc/guix.texi (operating-system Reference)
(Networking Services) (Virtualization Services): Rewrite documentation
entries to use hosts-service-type.
* gnu/tests/ganeti.scm: Use hosts-service-type extension.
---
WIP, the ganeti tests fail because host-name is added as an alias of localhost.
Ideally hosts-service-type should be moved to %base-services but we lose access
to os host-name if we do so.
doc/guix.texi | 60 +++++++++++++++++++++++---------------------
gnu/system.scm | 59 ++++++++++++++++++++++++++++++++-----------
gnu/tests/ganeti.scm | 18 ++++++-------
3 files changed, 85 insertions(+), 52 deletions(-)
Comments
Bruno Victal <mirai@makinata.eu> skribis:
> * gnu/system.scm (operating-system-hosts-file): Deprecate procedure.
> (warn-hosts-file-field-deprecation): New procedure, helper for
> deprecated variable).
> (operating-system)[hosts-file]: Use helper to warn deprecated field.
> (operating-system-default-essential-services)
> (hurd-default-essential-services): Use hosts-service-type.
> (local-host-aliases): Return a list of host-entry records.
> (default-/etc/hosts): Remove procedure.
> (operating-system-etc-service): Remove hosts file.
> * doc/guix.texi (operating-system Reference)
> (Networking Services) (Virtualization Services): Rewrite documentation
> entries to use hosts-service-type.
> * gnu/tests/ganeti.scm: Use hosts-service-type extension.
> ---
>
> WIP, the ganeti tests fail because host-name is added as an alias of localhost.
Before these patches, ‘host-name’ was already an alias of ‘localhost’.
Is there something else interfering?
> + (simple-service 'block-facebook-hosts hosts-service-type
> + (let ((host-pairs
> + (filter-map
> + (lambda (x)
> + (and (not (or (string-null? x)
> + (string-prefix? "#" x)))
> + (remove string-null?
> + (string-split
> + x
> + char-set:whitespace))))
> + (string-split %facebook-host-aliases #\newline))))
> + (map (match-lambda
> + ((addr name)
> + (host addr name)))
> + host-pairs)))
It doesn’t matter because it’s removed in the commit that follows I
think using ‘string-tokenize’ instead of ‘string-split’ may bring
simplifications.
> +++ b/gnu/system.scm
> @@ -14,6 +14,7 @@
> ;;; Copyright © 2020, 2022 Efraim Flashner <efraim@flashner.co.il>
> ;;; Copyright © 2021 Maxime Devos <maximedevos@telenet.be>
> ;;; Copyright © 2021 raid5atemyhomework <raid5atemyhomework@protonmail.com>
> +;;; Copyright © 2023 Bruno Victal <mirai@makinata.eu>
> ;;;
> ;;; This file is part of GNU Guix.
> ;;;
> @@ -31,6 +32,7 @@
> ;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
>
> (define-module (gnu system)
> + #:use-module (guix discovery)
Do we really need this module?
Otherwise LGTM.
Ludo’.
On 2023-01-23 22:37, Ludovic Courtès wrote:
> Bruno Victal <mirai@makinata.eu> skribis:
>
>> ---
>>
>> WIP, the ganeti tests fail because host-name is added as an alias of localhost.
>
> Before these patches, ‘host-name’ was already an alias of ‘localhost’.
> Is there something else interfering?
In some cases, it's not desired for host-name to be an alias of localhost.
The ganeti tests did this by passing a hosts-file file-like object where
host-name wasn't an alias of localhost.
I've brainstormed a bit on this and here's what I thought:
Approach 1 (DOESN'T WORK):
* hosts-service-type in essential-services (gnu/systems.scm), default value:
127.0.0.1 localhost
::1 localhost
* simple-service extension on base-services (gnu/services/base.scm):
\\FLOPS since both /etc/hosts and /etc/hostname are provisioned with activation-service-type.
This means we can't write /etc/hosts AFTER /etc/hostname or host-name-service-type is ready.
Approach 2:
* NO /etc/hosts in essential-services (is this possible?)
* is an absent /etc/hosts (or absent %base-services) a valid OS?
* Value set in %base-services, hosts-service-type as a ONE-SHOT shepherd service.
* Can be changed with modify-services.
* It's a one-shot shepherd service since we're depending on /etc/hostname which is activation-service-type. (we're depending on either etc-service-type or host-name-service-type)
Approach 3:
* Do not set our hostname as an alias of localhost by default.
* Manpage doesn't seem to make this mandatory, in fact, our hostname can point to any IP. (it says 'often', not 'mandatory')
* We only set localhost name.
* Is this mandatory? If not, there might be cases where this entry is undesired.
>
>> + (simple-service 'block-facebook-hosts hosts-service-type
>> + (let ((host-pairs
>> + (filter-map
>> + (lambda (x)
>> + (and (not (or (string-null? x)
>> + (string-prefix? "#" x)))
>> + (remove string-null?
>> + (string-split
>> + x
>> + char-set:whitespace))))
>> + (string-split %facebook-host-aliases #\newline))))
>> + (map (match-lambda
>> + ((addr name)
>> + (host addr name)))
>> + host-pairs)))
>
> It doesn’t matter because it’s removed in the commit that follows I
> think using ‘string-tokenize’ instead of ‘string-split’ may bring
> simplifications.
It was added because otherwise the "split" commits would seem to be missing some context.
I can leave it as is, delete it here or try your suggestion.
>> +++ b/gnu/system.scm
>> @@ -14,6 +14,7 @@
>> ;;; Copyright © 2020, 2022 Efraim Flashner <efraim@flashner.co.il>
>> ;;; Copyright © 2021 Maxime Devos <maximedevos@telenet.be>
>> ;;; Copyright © 2021 raid5atemyhomework <raid5atemyhomework@protonmail.com>
>> +;;; Copyright © 2023 Bruno Victal <mirai@makinata.eu>
>> ;;;
>> ;;; This file is part of GNU Guix.
>> ;;;
>> @@ -31,6 +32,7 @@
>> ;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
>>
>> (define-module (gnu system)
>> + #:use-module (guix discovery)
>
> Do we really need this module?
IIRC this was for the deprecated procedures to work. Can they work without this module?
Cheers,
Bruno
Hi Bruno!
Bruno Victal <mirai@makinata.eu> skribis:
> On 2023-01-23 22:37, Ludovic Courtès wrote:
>> Bruno Victal <mirai@makinata.eu> skribis:
>>
>>> ---
>>>
>>> WIP, the ganeti tests fail because host-name is added as an alias of localhost.
>>
>> Before these patches, ‘host-name’ was already an alias of ‘localhost’.
>> Is there something else interfering?
>
> In some cases, it's not desired for host-name to be an alias of localhost.
> The ganeti tests did this by passing a hosts-file file-like object where
> host-name wasn't an alias of localhost.
Oh, I see.
> I've brainstormed a bit on this and here's what I thought:
>
> Approach 1 (DOESN'T WORK):
> * hosts-service-type in essential-services (gnu/systems.scm), default value:
> 127.0.0.1 localhost
> ::1 localhost
> * simple-service extension on base-services (gnu/services/base.scm):
> \\FLOPS since both /etc/hosts and /etc/hostname are provisioned with activation-service-type.
> This means we can't write /etc/hosts AFTER /etc/hostname or host-name-service-type is ready.
>
> Approach 2:
> * NO /etc/hosts in essential-services (is this possible?)
> * is an absent /etc/hosts (or absent %base-services) a valid OS?
> * Value set in %base-services, hosts-service-type as a ONE-SHOT shepherd service.
> * Can be changed with modify-services.
> * It's a one-shot shepherd service since we're depending on /etc/hostname which is activation-service-type. (we're depending on either etc-service-type or host-name-service-type)
>
> Approach 3:
> * Do not set our hostname as an alias of localhost by default.
> * Manpage doesn't seem to make this mandatory, in fact, our hostname can point to any IP. (it says 'often', not 'mandatory')
> * We only set localhost name.
> * Is this mandatory? If not, there might be cases where this entry is undesired.
Wait, why don’t we keep ‘hosts-service-type’ in ‘essential-services’,
with the localhost/host-name alias, and have ‘%ganeti-os’ in (gnu tests
ganeti) modify its essential services to get what it wants? As in:
(operating-system
;; …
(essential-services
(modify-services (operation-system-default-essential-services this-operating-system)
(hosts-service-type config => …))))
Granted, that’s a bit verbose :-), but it should do the job just like
setting ‘hosts-file’ currently in ‘master’, no?
>> It doesn’t matter because it’s removed in the commit that follows I
>> think using ‘string-tokenize’ instead of ‘string-split’ may bring
>> simplifications.
>
> It was added because otherwise the "split" commits would seem to be missing some context.
> I can leave it as is, delete it here or try your suggestion.
Yeah leave it as is.
>>> + #:use-module (guix discovery)
>>
>> Do we really need this module?
>
> IIRC this was for the deprecated procedures to work. Can they work without this module?
Yes, ‘define-deprecated’ is defined in (guix deprecation).
Thanks!
Ludo’.
@@ -16479,13 +16479,6 @@ operating-system Reference
@item @code{host-name}
The host name.
-@item @code{hosts-file}
-@cindex hosts file
-A file-like object (@pxref{G-Expressions, file-like objects}) for use as
-@file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
-Reference Manual}). The default is a file with entries for
-@code{localhost} and @var{host-name}.
-
@item @code{mapped-devices} (default: @code{'()})
A list of mapped devices. @xref{Mapped Devices}.
@@ -21010,22 +21003,33 @@ Networking Services
on-line service---e.g., @code{www.facebook.com}---to the local
host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
-This variable is typically used in the @code{hosts-file} field of an
-@code{operating-system} declaration (@pxref{operating-system Reference,
-@file{/etc/hosts}}):
+This variable is typically used as a @code{hosts-service-type}
+service extension (@pxref{Service Reference, @code{hosts-service-type}}):
@lisp
-(use-modules (gnu) (guix))
+(use-modules (gnu) (gnu services) (guix) (srfi srfi-1) (ice-9 match))
+(use-service-modules networking)
(operating-system
- (host-name "mymachine")
- ;; ...
- (hosts-file
- ;; Create a /etc/hosts file with aliases for "localhost"
- ;; and "mymachine", as well as for Facebook servers.
- (plain-file "hosts"
- (string-append (local-host-aliases host-name)
- %facebook-host-aliases))))
+ ;; @dots{}
+
+ (service
+ (simple-service 'block-facebook-hosts hosts-service-type
+ (let ((host-pairs
+ (filter-map
+ (lambda (x)
+ (and (not (or (string-null? x)
+ (string-prefix? "#" x)))
+ (remove string-null?
+ (string-split
+ x
+ char-set:whitespace))))
+ (string-split %facebook-host-aliases #\newline))))
+ (map (match-lambda
+ ((addr name)
+ (host addr name)))
+ host-pairs)))
+ ;; @dots{}
@end lisp
This mechanism can prevent programs running locally, such as Web
@@ -34310,7 +34314,7 @@ Virtualization Services
services which are described later in this section. In addition to the Ganeti
service, you will need the OpenSSH service (@pxref{Networking Services,
@code{openssh-service-type}}), and update the @file{/etc/hosts} file
-(@pxref{operating-system Reference, @code{hosts-file}}) with the cluster name
+(@pxref{Service Reference, @code{hosts-service-type}}) with the cluster name
and address (or use a DNS server).
All nodes participating in a Ganeti cluster should have the same Ganeti and
@@ -34324,14 +34328,6 @@ Virtualization Services
(operating-system
;; @dots{}
(host-name "node1")
- (hosts-file (plain-file "hosts" (format #f "
-127.0.0.1 localhost
-::1 localhost
-
-192.168.1.200 ganeti.example.com
-192.168.1.201 node1.example.com node1
-192.168.1.202 node2.example.com node2
-")))
;; Install QEMU so we can use KVM-based instances, and LVM, DRBD and Ceph
;; in order to use the "plain", "drbd" and "rbd" storage backends.
@@ -34359,6 +34355,14 @@ Virtualization Services
(openssh-configuration
(permit-root-login 'prohibit-password)))
+ (simple-service 'ganeti-hosts-entries hosts-service-type
+ (list
+ (host "192.168.1.200" "ganeti.example.com")
+ (host "192.168.1.201" "node1.example.com"
+ '("node1"))
+ (host "192.168.1.202" "node2.example.com"
+ '("node2"))))
+
(service ganeti-service-type
(ganeti-configuration
;; This list specifies allowed file system paths
@@ -14,6 +14,7 @@
;;; Copyright © 2020, 2022 Efraim Flashner <efraim@flashner.co.il>
;;; Copyright © 2021 Maxime Devos <maximedevos@telenet.be>
;;; Copyright © 2021 raid5atemyhomework <raid5atemyhomework@protonmail.com>
+;;; Copyright © 2023 Bruno Victal <mirai@makinata.eu>
;;;
;;; This file is part of GNU Guix.
;;;
@@ -31,6 +32,7 @@
;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
(define-module (gnu system)
+ #:use-module (guix discovery)
#:use-module (guix inferior)
#:use-module (guix store)
#:use-module (guix memoization)
@@ -97,7 +99,7 @@ (define-module (gnu system)
operating-system-user-services
operating-system-packages
operating-system-host-name
- operating-system-hosts-file
+ operating-system-hosts-file ;deprecated
operating-system-hurd
operating-system-kernel
operating-system-kernel-file
@@ -208,6 +210,15 @@ (define* (bootable-kernel-arguments system root-device version)
#$system "/boot")))
;; System-wide configuration.
+
+(define-with-syntax-properties (warn-hosts-file-field-deprecation
+ (value properties))
+ (when value
+ (warning (source-properties->location properties)
+ (G_ "the 'hosts-file' field is deprecated, please use \
+'hosts-service-type' instead~%")))
+ value)
+
;; TODO: Add per-field docstrings/stexi.
(define-record-type* <operating-system> operating-system
make-operating-system
@@ -239,8 +250,9 @@ (define-record-type* <operating-system> operating-system
(default %base-firmware))
(host-name operating-system-host-name) ; string
- (hosts-file operating-system-hosts-file ; file-like | #f
- (default #f))
+ (hosts-file %operating-system-hosts-file ; deprecated
+ (default #f)
+ (sanitize warn-hosts-file-field-deprecation))
(mapped-devices operating-system-mapped-devices ; list of <mapped-device>
(default '()))
@@ -296,6 +308,10 @@ (define-record-type* <operating-system> operating-system
source-properties->location))
(innate)))
+(define-deprecated (operating-system-hosts-file os)
+ hosts-service-type
+ (%operating-system-hosts-file os))
+
(define* (operating-system-kernel-arguments
os root-device #:key (version %boot-parameters-version))
"Return all the kernel arguments, including the ones not specified directly
@@ -733,7 +749,8 @@ (define (operating-system-default-essential-services os)
(non-boot-fs (non-boot-file-system-service os))
(swaps (swap-services os))
(procs (service user-processes-service-type))
- (host-name (host-name-service (operating-system-host-name os)))
+ (host-name (operating-system-host-name os))
+ (hosts-file (operating-system-hosts-file os))
(entries (operating-system-directory-base-entries os)))
(cons* (service system-service-type entries)
(service linux-builder-service-type
@@ -755,12 +772,19 @@ (define (operating-system-default-essential-services os)
(operating-system-groups os))
(operating-system-skeletons os))
(operating-system-etc-service os)
+ ;; XXX: hosts-file is deprecated
+ (if hosts-file
+ (simple-service 'deprecated-hosts-file etc-service-type
+ (list `("hosts" ,hosts-file)))
+ (service hosts-service-type
+ (local-host-aliases host-name)))
(service fstab-service-type
(filter file-system-needed-for-boot?
(operating-system-file-systems os)))
(session-environment-service
(operating-system-environment-variables os))
- host-name procs root-fs
+ (host-name-service host-name)
+ procs root-fs
(service setuid-program-service-type
(operating-system-setuid-programs os))
(service profile-service-type
@@ -774,7 +798,9 @@ (define (operating-system-default-essential-services os)
(operating-system-firmware os)))))))
(define (hurd-default-essential-services os)
- (let ((entries (operating-system-directory-base-entries os)))
+ (let ((host-name (operating-system-host-name os))
+ (hosts-file (operating-system-hosts-file os))
+ (entries (operating-system-directory-base-entries os)))
(list (service system-service-type entries)
%boot-service
%hurd-startup-service
@@ -794,6 +820,12 @@ (define (hurd-default-essential-services os)
(operating-system-file-systems os)))
(pam-root-service (operating-system-pam-services os))
(operating-system-etc-service os)
+ ;; XXX: hosts-file is deprecated
+ (if hosts-file
+ (simple-service 'deprecated-hosts-file etc-service-type
+ (list `("hosts" ,hosts-file)))
+ (service hosts-service-type
+ (local-host-aliases host-name)))
(service setuid-program-service-type
(operating-system-setuid-programs os))
(service profile-service-type (operating-system-packages os)))))
@@ -914,12 +946,13 @@ (define %default-issue
(define (local-host-aliases host-name)
"Return aliases for HOST-NAME, to be used in /etc/hosts."
- (string-append "127.0.0.1 localhost " host-name "\n"
- "::1 localhost " host-name "\n"))
-
-(define (default-/etc/hosts host-name)
- "Return the default /etc/hosts file."
- (plain-file "hosts" (local-host-aliases host-name)))
+ (map (lambda (address)
+ (host-entry
+ (address address)
+ (canonical-name "localhost")
+ (aliases (list host-name))))
+ '("127.0.0.1"
+ "::1")))
(define (validated-sudoers-file file)
"Return a copy of FILE, a sudoers file, after checking that it is
@@ -1068,8 +1101,6 @@ (define* (operating-system-etc-service os)
,@(if nsswitch `(("nsswitch.conf" ,#~#$nsswitch)) '())
("profile" ,#~#$profile)
("bashrc" ,#~#$bashrc)
- ("hosts" ,#~#$(or (operating-system-hosts-file os)
- (default-/etc/hosts (operating-system-host-name os))))
;; Write the operating-system-host-name to /etc/hostname to prevent
;; NetworkManager from changing the system's hostname when connecting
;; to certain networks. Some discussion at
@@ -46,16 +46,6 @@ (define %ganeti-os
%base-file-systems))
(firmware '())
- ;; The hosts file must contain a nonlocal IP for host-name.
- ;; In addition, the cluster name must resolve to an IP address that
- ;; is not currently provisioned.
- (hosts-file (plain-file "hosts" (format #f "
-127.0.0.1 localhost
-::1 localhost
-10.0.2.15 gnt1.example.com gnt1
-192.168.254.254 ganeti.example.com
-")))
-
(packages (append (list ganeti-instance-debootstrap ganeti-instance-guix)
%base-packages))
(services
@@ -65,6 +55,14 @@ (define %ganeti-os
(openssh-configuration
(permit-root-login 'prohibit-password)))
+ ;; The hosts file must contain a nonlocal IP for host-name.
+ ;; In addition, the cluster name must resolve to an IP address that
+ ;; is not currently provisioned.
+ (simple-service 'ganeti-host-entries hosts-service-type
+ (list
+ (host "10.0.2.15" "gnt1.example.com" '("gnt1"))
+ (host "192.168.254.254" "ganeti.example.com")))
+
(service ganeti-service-type
(ganeti-configuration
(file-storage-paths '("/srv/ganeti/file-storage"))