From: ludo@gnu.org (Ludovic Courtès)
To: 宋文武 <iyzsong@gmail.com>
Cc: guix-devel <guix-devel@gnu.org>
Subject: Re: Service refactoring
Date: Thu, 24 Sep 2015 19:09:02 +0200 [thread overview]
Message-ID: <87oagrycb5.fsf@gnu.org> (raw)
In-Reply-To: <CAHZE2penDA6dGsy-T_JqEKFZ97ZsL9cBq3kR+HdkcZo=wuM_pw@mail.gmail.com> ("宋文武"'s message of "Thu, 24 Sep 2015 17:33:07 +0800")
宋文武 <iyzsong@gmail.com> skribis:
> 2015-09-24 15:41 GMT+08:00 Ludovic Courtès <ludo@gnu.org>:
>> "Thompson, David" <dthompson2@worcester.edu> skribis:
>>
>>> On Mon, Sep 21, 2015 at 12:00 PM, Ludovic Courtès <ludo@gnu.org> wrote:
>>>> Andy Wingo <wingo@igalia.com> skribis:
>>>>
>>>>> On Sun 20 Sep 2015 15:42, ludo@gnu.org (Ludovic Courtès) writes:
>>>>>
>>>>>> I’m quite happy with the result, but comments are welcome! I’ll convert
>>>>>> some more services to see how it goes.
>>>>>
>>>>> Neat! Sounds great. One question: there are some services like colord
>>>>> or geoclue that don't need to be managed by DMD, but are just declared
>>>>> as services so that their users are created, there /var/foo directories
>>>>> are created, etc. The can be started by D-Bus as needed. Does the new
>>>>> design support services of this kind?
>>>>
>>>> Yes it does.
> Great news! I don't miss NixOS's modules anymore :-)
Heheh, NixOS modules are a very good competitor. ;-)
I think this model handles multiple service instances better than NixOS
modules. NixOS services can be enabled/disabled, for instance with
‘services.httpd.enable = true’ or ‘services.openssh.enable = true’, but
I don’t think there’s a general mechanism to have multiple instances of
httpd or sshd.
Also in NixOS any service can do ‘foo.bar = baz’ and change an unrelated
OS setting, which is not possible here.
I find the fixed-point approach of NixOS modules very elegant, but it
also complicates things: It’s easy to enter an infinite recursion, and
one has to carefully use ‘mkIf’ and similar constructs where it matters,
which is non-obvious.
> I think the difference is that we don't seperate options and implementations
> like NixOS did, 'service-type' have both in one place.
‘service-type’ is sort-of an interface: it describes how services are
composed, but not what they do.
> So, our services is highly tie to gexps and dmd (that's ok).
The whole thing is rather tied to gexps, but it’s not tied to dmd. dmd
is just a service that has nothing special, and (gnu system) does not
embed any knowledge about dmd.
The only service type that’s known to (gnu system) is
‘boot-service-type’.
Thanks for your feedback!
Ludo’.
next prev parent reply other threads:[~2015-09-24 17:09 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-09-03 21:23 [PATCHES] Get elogind-service working as intended Mark H Weaver
2015-09-04 7:57 ` Andy Wingo
2015-09-06 21:23 ` Service refactoring Ludovic Courtès
2015-09-08 8:47 ` Andy Wingo
2015-09-08 10:12 ` Ludovic Courtès
2015-09-08 10:33 ` Andy Wingo
2015-09-08 14:48 ` Mark H Weaver
2015-09-10 16:05 ` Ludovic Courtès
2015-09-10 16:14 ` Ludovic Courtès
2015-09-20 15:42 ` Ludovic Courtès
2015-09-21 8:18 ` Andy Wingo
2015-09-21 16:00 ` Ludovic Courtès
2015-09-24 0:33 ` Thompson, David
2015-09-24 7:41 ` Ludovic Courtès
2015-09-24 9:33 ` 宋文武
2015-09-24 17:09 ` Ludovic Courtès [this message]
2015-09-25 22:50 ` Christopher Allan Webber
2015-09-26 12:50 ` Ludovic Courtès
2015-09-30 8:59 ` Ludovic Courtès
2015-10-10 21:01 ` Ludovic Courtès
2015-09-10 16:03 ` [PATCHES] Get elogind-service working as intended Ludovic Courtès
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