From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <t.lamprecht@proxmox.com> Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id 7140363408 for <pve-devel@lists.proxmox.com>; Mon, 21 Sep 2020 13:12:27 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 586A124C6A for <pve-devel@lists.proxmox.com>; Mon, 21 Sep 2020 13:11:57 +0200 (CEST) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [212.186.127.180]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS id 0AABB24C5D for <pve-devel@lists.proxmox.com>; Mon, 21 Sep 2020 13:11:56 +0200 (CEST) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id C72524546C for <pve-devel@lists.proxmox.com>; Mon, 21 Sep 2020 13:11:55 +0200 (CEST) To: Proxmox VE development discussion <pve-devel@lists.proxmox.com>, Aaron Lauterer <a.lauterer@proxmox.com> References: <20200910143242.20898-1-a.lauterer@proxmox.com> <20200910143242.20898-4-a.lauterer@proxmox.com> <d780fc9a-c735-fb83-5ba4-f4cb1afbaef3@proxmox.com> <a3f146e9-5b0e-2949-c9fe-fe62f167900e@proxmox.com> From: Thomas Lamprecht <t.lamprecht@proxmox.com> Message-ID: <a87b1c0c-3dd2-2faf-1662-5884d06c1b79@proxmox.com> Date: Mon, 21 Sep 2020 13:11:54 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:81.0) Gecko/20100101 Thunderbird/81.0 MIME-Version: 1.0 In-Reply-To: <a3f146e9-5b0e-2949-c9fe-fe62f167900e@proxmox.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable X-SPAM-LEVEL: Spam detection results: 0 AWL -0.187 Adjusted score from AWL reputation of From: address KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment NICE_REPLY_A -0.001 Looks like a legit reply (A) RCVD_IN_DNSWL_MED -2.3 Sender listed at https://www.dnswl.org/, medium trust SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Subject: Re: [pve-devel] [PATCH v3 storage 3/4] add disk reassign feature X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion <pve-devel.lists.proxmox.com> List-Unsubscribe: <https://lists.proxmox.com/cgi-bin/mailman/options/pve-devel>, <mailto:pve-devel-request@lists.proxmox.com?subject=unsubscribe> List-Archive: <http://lists.proxmox.com/pipermail/pve-devel/> List-Post: <mailto:pve-devel@lists.proxmox.com> List-Help: <mailto:pve-devel-request@lists.proxmox.com?subject=help> List-Subscribe: <https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel>, <mailto:pve-devel-request@lists.proxmox.com?subject=subscribe> X-List-Received-Date: Mon, 21 Sep 2020 11:12:27 -0000 On 18.09.20 17:07, Aaron Lauterer wrote: >=20 >=20 > On 9/18/20 4:24 PM, Thomas Lamprecht wrote: >> On 9/10/20 4:32 PM, Aaron Lauterer wrote: >>> Functionality has been added for the following storage types: >>> >>> * dir based ones >>> =C2=A0=C2=A0=C2=A0=C2=A0 * directory >>> =C2=A0=C2=A0=C2=A0=C2=A0 * NFS >>> =C2=A0=C2=A0=C2=A0=C2=A0 * CIFS >>> =C2=A0=C2=A0=C2=A0=C2=A0 * gluster >>> * ZFS >>> * (thin) LVM >>> * Ceph >>> >>> A new feature `reassign` has been introduced to mark which storage >>> plugin supports the feature. >>> >>> A new intermediate class for directory based storages has been >>> introduced. This was necessary to maintain compatibility with third >>> party storage plugins and to avoid duplicate code in the dir based >>> plugins. >>> >>> The new `BaseDirPlugin.pm` adds the `reassign` feature flag and >>> containes the implementation for the reassign functionlity. >>> >>> In the future all the directory specific code in Plugin.pm should be >>> moved to the BaseDirPlugin.pm. But this will most likely break >>> compatibility with third party plugins and should thus be done with >>> care. >> >> how so? why don't you just add it in plugin.pm with either: >> * a general directory based implementation, and a no-op/die for the ot= her >> =C2=A0=C2=A0 ones >=20 > That was the first approach, but this would mean a die for all other pl= ugins and if 3rd party plugins would not implement it, the directory base= d code will be used. But we cannot know if if the directory approach is t= he right one. Note that you also can check the APIVERSION of external plugins through the "api" method, which is required for them and checked on loading. >=20 >> * a dummy "die implement me in subclass" method if above is not possib= le >=20 > If I do it this way, I cannot put the actual code for dir based storage= in the Plugin.pm, thus having an intermediate class for dir based storag= es would still be beneficial IMHO to avoid code duplication. IIRC we have= 4 dir based storages (dir, CIFS, NFS, Gluster). code duplication can also be avoided by just having a general method some= where which the single plugins just wrap around (call). That just "duplicates" the calls, which is no actual duplication as it provides concrete informa= tion about what which plugin uses they all share the implementation, which is = the actual reason for avoiding code duplication. IMO a saner and more understandable than this approach, plus external plu= gins can just call into this if it works for them.