From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mp10.migadu.com ([2001:41d0:8:6d80::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by ms5.migadu.com with LMTPS id SHPbE98QqmJC2AAAbAwnHQ (envelope-from ) for ; Wed, 15 Jun 2022 19:03:27 +0200 Received: from aspmx1.migadu.com ([2001:41d0:8:6d80::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by mp10.migadu.com with LMTPS id QHP9Et8QqmJ+jgAAG6o9tA (envelope-from ) for ; Wed, 15 Jun 2022 19:03:27 +0200 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by aspmx1.migadu.com (Postfix) with ESMTPS id E2CB424CFF for ; Wed, 15 Jun 2022 19:03:26 +0200 (CEST) Received: from localhost ([::1]:39356 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1o1WQP-0000tQ-KS for larch@yhetil.org; Wed, 15 Jun 2022 13:03:25 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:60536) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1o1WP4-0000VM-7N for guix-devel@gnu.org; Wed, 15 Jun 2022 13:02:02 -0400 Received: from mail-ej1-x631.google.com ([2a00:1450:4864:20::631]:43787) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1o1WP1-0004MV-H5 for guix-devel@gnu.org; Wed, 15 Jun 2022 13:02:01 -0400 Received: by mail-ej1-x631.google.com with SMTP id m20so24436591ejj.10 for ; Wed, 15 Jun 2022 10:01:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sweatshoppe-org.20210112.gappssmtp.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=qxVbxsntiD1kCXG5jR6L+4RsY4FJG2Atjt32t/SmHok=; b=YLWlZruW/4skwMMlfZulPObsm5qE+jiuzvekSD0VOumVBN+TmlTGjUc+iytItDUmS8 eDL/JJq6kXNdMBkdnoXCzw1FNgYyLhVgV0LCVGqwixsOJdopjA+ZKysK+zFeBRFmjTdL /dDp8FI6oYQM3bYRSoBWcw5+a6f3k+QJid+lj+eYSMLr0brCy7A84XkyZxACEnfhm7b3 1rOzoCWVm7EUdCL8yVuvhDyFxaqbBP45gV4jk7KD0XslvKP7cH1nnJ+gkEO6e6ImVSMR LAtO1lZSLcOPwv5qV1O00QJw+h/2ChhyAuZbeJzVq9790LP+06mKp5xxKml4LCcwsfkl FiaQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=qxVbxsntiD1kCXG5jR6L+4RsY4FJG2Atjt32t/SmHok=; b=GeU4RRp2hq8oIU6c5m/2tn9FzVwl1yLj9bvg0T17DX1sLzJtWCzwSrrUi/akHaG9yG Iy3Vj4s2ncjf3n/RK16M4r6ao0EB3NxrrBlhxmb0ci88Z1dXnFTSVc4erqBiWSx/ehcv x7GgB6X6C6E2D9Z5jrVOXuZZ9e2EUljGqXcozUvt4d1DRsnJ+1Y8sIptIDKelKfTcIuX lL9z/LmT435d5Md8NXIKpCgEvZKtpioxR9rv51wdDM4QwIOgBj9jmeFIa2i82EZ32RiH W6qTLWn+yul4TTsQSPDATvqnivd1H8Aw066KNwDwRJc+3GpC5s0yBHkygQRyxqXPweA1 +YfA== X-Gm-Message-State: AJIora8SbXNv10OEE7esAnZpqsxuBCT0FjDADE8WLTGHbGVGecsQ1/Sd hat0HgQx7FzLbmb8MpMLcQPsHerVO6QWBPcVStgI/g== X-Google-Smtp-Source: AGRyM1sAbVu3EeTnjUL1djoZs9211aWJXv3S7WzJs4US6x3aprvJqyBzsgufTKpNsB/hROi+ku4LNmpDNSa5rDhsMgI= X-Received: by 2002:a17:906:7d83:b0:6ce:fee:9256 with SMTP id v3-20020a1709067d8300b006ce0fee9256mr676913ejo.647.1655312516685; Wed, 15 Jun 2022 10:01:56 -0700 (PDT) MIME-Version: 1.0 References: <87a6as62r2.fsf@elephly.net> <87ilpfwmi0.fsf@jpoiret.xyz> <877d5j5vng.fsf@trop.in> <87a666663179c883aaa1797b62c3bcb0084d3ebb.camel@gmail.com> <87bkuuyqf9.fsf@elephly.net> In-Reply-To: <87bkuuyqf9.fsf@elephly.net> From: Blake Shaw Date: Wed, 15 Jun 2022 17:01:44 +0000 Message-ID: Subject: Re: how to write services (was: Re: Teams) To: Ricardo Wurmus Cc: catonano@gmail.com, Andrew Tropin , Josselin Poiret , Guix Devel , GNU Guix maintainers Content-Type: multipart/alternative; boundary="0000000000008cc14605e17f7ac6" Received-SPF: none client-ip=2a00:1450:4864:20::631; envelope-from=blake@sweatshoppe.org; helo=mail-ej1-x631.google.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_NONE=0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: guix-devel@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+larch=yhetil.org@gnu.org Sender: "Guix-devel" X-Migadu-Flow: FLOW_IN X-Migadu-To: larch@yhetil.org X-Migadu-Country: US ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1655312607; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to: references:references:list-id:list-help:list-unsubscribe: list-subscribe:list-post:dkim-signature; bh=qxVbxsntiD1kCXG5jR6L+4RsY4FJG2Atjt32t/SmHok=; b=C1v/BZYDXXYoaZf/I7qJLIeIfCdNB7teZ2uIJs9Jvm11Uj9Tn1RRiCl8ypGpiBLuIjJ5VD 7t1Ald3mFBp4qF6OATLNgFH29RAbLxLK+v1VVmVmam5Luza74wOmkpUm7PR9VhBea+xRKv OWzIrz7uFV2Ow7Fx08zUqRa+fOaczaKphA6Kml/nKf3PUHI6EPxZOe2ihuJynnu6s3077h eQEKzyO2VcqkuNUOi5FtBlIh/ie+kDPhfOhMMJ5BaLyOxP74pbz2qpGmfhNfFRn0I151Za JaZzzqDQ9H0aa6ekqj4v36uBtXXaVZAR3iLlNeBsf/q9EmnBOLi7W3rbDaeQ9Q== ARC-Seal: i=1; s=key1; d=yhetil.org; t=1655312607; a=rsa-sha256; cv=none; b=b6dEHVCV+09sRBSxMzV4HAWn+2Rew+D4/8QUOhNkl8pM+SxcmRy6PIduZAPb4oFz6OaU82 4VyxtZHN85yMNwGQBTqSCiiex4xYQ7cm1gaPn/GlRaXWykbfwzSvHrRuqeMJwqKCjpDtqT 4wbsTnkTAoRN2mSPx1VUA/hKPUjpZ/kHwbV1LkG3SI5gJdllFqPLrNZAdVwHswdrCjaYMp 4oU4tYCs+pPbj/5UOhfzjQYz0yzY9qn2Lzp4mJI9bsgNJpoNv8AayrFKscoxesq7dd59mo ma6vO1kglwWRTgtHofteq0/Zw7KGdheS17QrFno8HWT/Vd8Apd7YptWOID3Lew== ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=pass header.d=sweatshoppe-org.20210112.gappssmtp.com header.s=20210112 header.b=YLWlZruW; dmarc=none; spf=pass (aspmx1.migadu.com: domain of "guix-devel-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="guix-devel-bounces+larch=yhetil.org@gnu.org" X-Migadu-Spam-Score: -8.09 Authentication-Results: aspmx1.migadu.com; dkim=pass header.d=sweatshoppe-org.20210112.gappssmtp.com header.s=20210112 header.b=YLWlZruW; dmarc=none; spf=pass (aspmx1.migadu.com: domain of "guix-devel-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="guix-devel-bounces+larch=yhetil.org@gnu.org" X-Migadu-Queue-Id: E2CB424CFF X-Spam-Score: -8.09 X-Migadu-Scanner: scn0.migadu.com X-TUID: bewSq7rb1Vcb --0000000000008cc14605e17f7ac6 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Ricardo: Thats very good advice and will be a useful guide in refactoring the parts of the system services documentation. I think in general, we need to find a nice middle ground between the extremely general and the immediately sensible, as I remember when I first got into guix 1.5 years ago, arriving at services left me very confused. While as a recent PhD candidate in philosophy of mathematics I'm a fellow appreciator of the power of generality (the extreme genericity of scheme and guix is why I'm here!), I also think if it doesn't obey strict linguistic rules it can antithetical to its original purpose. For example, I remember being very confused about "file-like objects", for the simple reason that it wasn't "a file or file-like object". While this might come from a GNU terminological lineage i'm unaware of, my immediate reaction to trying to understand file-likeness is the simple rule that a semblance is strictly not what it resembles, and likeness qualifies semblance. It would be improper to place phones in a category of "phone-like objects", because the likeness assumes a distinction from the thing itself. Perhaps it could be justified if we dive into the minutiae of paraconsistent logic, but I think then we are going to far (also, isn't 'everything a file' a motto of Unix, even if gnu is strictly not?). But I've digressed; I think your straightforward description above communicates many of the ideas better than the docs, but I think this is a situation where we can have our cake and eat it too, so to speak; usually, an appendage such as "file AND file-like objects" will accomplish much of the work for us. Catonano: I think writing a home-service is much easier given that you don't need to do produce an entire system generation before you find out what you did wrong; it just depends on if you need your service initialized at startup (system-services, globally defined and available prior to login) rather than at login (home-services, per-user/locally defined). I'm not on Mastodon but feel free to send your service my way for some help, I'm still a beginner but a second pair of eyes is always nice to have= . ez, b --- Blake Shaw Director, SWEATSHOPPE sweatshoppe.org --- On Wed, Jun 15, 2022 at 2:04 PM Ricardo Wurmus wrote: > > catonano@gmail.com writes: > > > Il giorno mer, 15/06/2022 alle 01.52 +0700, Blake Shaw ha scritto: > >> > >> I found the documentation to be a bit confusing (understandably, as > >> its new), but once the workflow snapped together its been amazing to > >> see how easy it is to create new services. > > > > This is something I'm specifically interested in > > > > In fact, I wrote this toot that got several boosts and likes but NO > > answer > > https://floss.social/web/@abbienormal/108378060174601402 > > I don=E2=80=99t know Odoo, but the general process is this: > > - look up the relevant documentation of your application to figure out > what commands must be executed. Take note of any way to pass a > configuration file. > > - copy an existing shepherd service. Maybe start with > gnu/services/audio.scm, because it=E2=80=99s pretty simple while not co= mpletely > trivial. > > - adjust the commands and names. > > In gnu/services/audio.scm you see the definition of mpd-service-type, > which is a *system* service that 1) adds a user account, 2) does some > one-shot preparation work, and 3) registers the mpd-shepherd-service. > > mpd-shepherd-service is a procedure returning a shepherd service. The > service has a start and stop command. Adjust this for your service. > > mpd-shepherd-service refers to its argument =E2=80=9Cconfig=E2=80=9D, whi= ch is supposed > to be a Scheme configuration value. It=E2=80=99s just a record defined h= igher > up as . mpd-config->file turns that Scheme value > into a string that can live in a file as the mpd configuration file. > > This is pretty much all there is to it. Some services are simpler and > don=E2=80=99t need any one-shot setup, nor do they need system user accou= nts, so > they would just boil down to a shepherd service definition. > > -- > Ricardo > --0000000000008cc14605e17f7ac6 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Ricardo:
Thats very good advice and will be= a useful guide in refactoring the parts of the system services documentati= on. I think in general, we need to find a nice middle ground between the ex= tremely general and the immediately sensible, as I remember when I first go= t into guix 1.5 years ago, arriving at services left me very confused. Whil= e as a recent PhD candidate in philosophy of mathematics I'm a fellow = appreciator of the power of generality (the extreme genericity of scheme an= d guix is why I'm here!), I also think if it doesn't obey strict li= nguistic rules it can antithetical to its original purpose. For example, I = remember being very confused about "file-like objects", for the s= imple reason that it wasn't "a file or file-like object". Whi= le this might come from a GNU terminological lineage i'm unaware of, my= immediate reaction to trying to understand file-likeness is the simple rul= e that a semblance is strictly not what it resembles, and likeness qualifie= s semblance. It would be improper to place phones in a category of "ph= one-like objects", because the likeness assumes a distinction from the= thing itself. Perhaps it could be justified if we dive into the minutiae o= f paraconsistent logic, but I think then we are going to far (also, isn'= ;t 'everything a file' a motto of Unix, even if gnu is strictly not= ?). But I've digressed; I think your straightforward description above = communicates many of the ideas better than the docs, but I think this is a = situation where we can have our cake and eat it too, so to speak; usually, = an appendage such as "file AND file-like objects" will accomplish= much of the work for us.

Catonano:
I th= ink writing a home-service is much easier given that you don't need to = do produce an entire system generation before you find out what you did wro= ng; it just depends on if you need your service initialized at startup (sys= tem-services, globally defined and available prior to login) rather than at= login (home-services, per-user/locally defined).

= I'm not on Mastodon but feel free to send your service my way for some = help, I'm still a beginner but a second pair of eyes is always nice to = have.

ez,
b

=

---
Bl= ake Shaw
Director, SWEATSHOPPE
sweatshoppe.org
---


<= div class=3D"gmail_quote">
On Wed, Jun= 15, 2022 at 2:04 PM Ricardo Wurmus <rekado@elephly.net> wrote:

catonano@gmail.com<= /a> writes:

> Il giorno mer, 15/06/2022 alle 01.52 +0700, Blake Shaw ha scritto:
>>
>> I found the documentation to be a bit confusing (understandably, a= s
>> its new), but once the workflow snapped together its been amazing = to
>> see how easy it is to create new services.=C2=A0
>
> This is something I'm specifically interested in
>
> In fact, I wrote this toot that got several boosts and likes but NO > answer
> https://floss.social/web/@abbienormal/1= 08378060174601402

I don=E2=80=99t know Odoo, but the general process is this:

- look up the relevant documentation of your application to figure out
=C2=A0 what commands must be executed.=C2=A0 Take note of any way to pass a=
=C2=A0 configuration file.

- copy an existing shepherd service.=C2=A0 Maybe start with
=C2=A0 gnu/services/audio.scm, because it=E2=80=99s pretty simple while not= completely
=C2=A0 trivial.

- adjust the commands and names.

In gnu/services/audio.scm you see the definition of mpd-service-type,
which is a *system* service that 1) adds a user account, 2) does some
one-shot preparation work, and 3) registers the mpd-shepherd-service.

mpd-shepherd-service is a procedure returning a shepherd service.=C2=A0 The=
service has a start and stop command.=C2=A0 Adjust this for your service.
mpd-shepherd-service refers to its argument =E2=80=9Cconfig=E2=80=9D, which= is supposed
to be a Scheme configuration value.=C2=A0 It=E2=80=99s just a record define= d higher
up as <mpd-configuration>.=C2=A0 mpd-config->file turns that Schem= e value
into a string that can live in a file as the mpd configuration file.

This is pretty much all there is to it.=C2=A0 Some services are simpler and=
don=E2=80=99t need any one-shot setup, nor do they need system user account= s, so
they would just boil down to a shepherd service definition.

--
Ricardo
--0000000000008cc14605e17f7ac6--