From debbugs-submit-bounces@debbugs.gnu.org Wed Mar 11 09:51:02 2020 Received: (at 39258) by debbugs.gnu.org; 11 Mar 2020 13:51:02 +0000 Received: from localhost ([127.0.0.1]:53799 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1jC1lG-0005CI-EP for submit@debbugs.gnu.org; Wed, 11 Mar 2020 09:51:02 -0400 Received: from eggs.gnu.org ([209.51.188.92]:48400) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1jC1lF-0005Bp-AH for 39258@debbugs.gnu.org; Wed, 11 Mar 2020 09:51:01 -0400 Received: from fencepost.gnu.org ([2001:470:142:3::e]:60359) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1jC1l8-0008MN-Ek; Wed, 11 Mar 2020 09:50:54 -0400 Received: from [2a01:e0a:1d:7270:af76:b9b:ca24:c465] (port=37924 helo=ribbon) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1jC1l7-0002rc-Fq; Wed, 11 Mar 2020 09:50:53 -0400 From: =?utf-8?Q?Ludovic_Court=C3=A8s?= To: Arun Isaac Subject: Re: [PATCH v2 0/3] Xapian for Guix package search References: <20200307133116.11443-1-arunisaac@systemreboot.net> <87sgijgb1v.fsf@gnu.org> <875zffcc87.fsf@gnu.org> <87r1y13jew.fsf@gnu.org> X-URL: http://www.fdn.fr/~lcourtes/ X-Revolutionary-Date: 22 =?utf-8?Q?Vent=C3=B4se?= an 228 de la =?utf-8?Q?R?= =?utf-8?Q?=C3=A9volution?= X-PGP-Key-ID: 0x090B11993D9AEBB5 X-PGP-Key: http://www.fdn.fr/~lcourtes/ludovic.asc X-PGP-Fingerprint: 3CE4 6455 8A84 FDC6 9DB4 0CFB 090B 1199 3D9A EBB5 X-OS: x86_64-pc-linux-gnu Date: Wed, 11 Mar 2020 14:50:51 +0100 In-Reply-To: (Arun Isaac's message of "Tue, 10 Mar 2020 19:47:57 +0530") Message-ID: <87sgifj8zo.fsf@gnu.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Spam-Score: -0.7 (/) X-Debbugs-Envelope-To: 39258 Cc: mail@ambrevar.xyz, 39258@debbugs.gnu.org, zimon.toutoune@gmail.com X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -1.7 (-) Hello! Arun Isaac skribis: >> We could provide a substitute for users who use only the official 'guix >> channel. However, as soon as users combine multiple channels, they=E2= =80=99ll >> have to build the index locally. > > We could build a separate Xapian database for each channel. Xapian does > support searching across multiple databases at once and will handle > merging the results together appropriately. Nice! > If I understand correctly, this means we can provide substitutes for > at least the official guix channel and let the user build the index > locally for other channels. Is that correct? I=E2=80=99m afraid not, or at least not trivially. Currently, profile hooks such as =E2=80=98%channel-profile-hooks=E2=80=99, = receive a complete profile=E2=80=94in this case, the composition of all the channels = the user chose. So if we want to achieve what you propose, we=E2=80=99d need to find anothe= r way to hook database generation. BTW, there=E2=80=99s also the problem of modules added dynamically with $GUIX_PACKAGE_PATH or =E2=80=98-L=E2=80=99. With the proposed scheme, it s= eems that they could no longer be searched. Is that correct? (Conversely the package cache is optional: it=E2=80=99s only used when it= =E2=80=99s considered authoritative, see (gnu packages). The API and behavior are exactly the same whether or not the package cache is used.) Thanks, Ludo=E2=80=99.