From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A31DBC48BCF for ; Wed, 9 Jun 2021 11:58:15 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 595BE61263 for ; Wed, 9 Jun 2021 11:58:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 595BE61263 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:60500 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lqwqc-0005fr-EK for qemu-devel@archiver.kernel.org; Wed, 09 Jun 2021 07:58:14 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:35458) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lqwpp-0004yj-LF for qemu-devel@nongnu.org; Wed, 09 Jun 2021 07:57:26 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:28719) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lqwpn-0003rB-Al for qemu-devel@nongnu.org; Wed, 09 Jun 2021 07:57:25 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1623239842; h=from:from: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; bh=+yDJ28kUQREtEIdkFEECQlmJHr8QC+h0oEDecV2PLag=; b=KhBDq4L/H/kkDvzQBiFzOvjRisEcG9u8ZITqXIAK+nwfAX+BPFNrtnPnKa1fExPblRuWhz jyfEYyy6kV5YmhZc5ASgs0QjZ6vu8i/gDvxMhRSTd3dSdN6AMTqYkfojy8EsDlTJ+PsTiL dTRFJCwgDLmv6P+JcYCdoSYCvOT1HZU= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-359-jHvH-7HTOMqoniqfIL5lHA-1; Wed, 09 Jun 2021 07:57:19 -0400 X-MC-Unique: jHvH-7HTOMqoniqfIL5lHA-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0F537A0BD1; Wed, 9 Jun 2021 11:57:18 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-112-222.ams2.redhat.com [10.36.112.222]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 04E66105C88C; Wed, 9 Jun 2021 11:56:41 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 800A5113865F; Wed, 9 Jun 2021 13:56:39 +0200 (CEST) From: Markus Armbruster To: John Snow Subject: Re: GSoC Intro - TUI interface for QMP References: <87czswxuwn.fsf@dusky.pond.sub.org> <1577ce78-bf98-3f3d-7594-2b91d84967ec@redhat.com> Date: Wed, 09 Jun 2021 13:56:39 +0200 In-Reply-To: <1577ce78-bf98-3f3d-7594-2b91d84967ec@redhat.com> (John Snow's message of "Tue, 8 Jun 2021 11:49:41 -0400") Message-ID: <87sg1rp7yg.fsf@dusky.pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=armbru@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain Received-SPF: pass client-ip=216.205.24.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.199, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, ehabkost@redhat.com, qemu-devel@nongnu.org, wainersm@redhat.com, "Niteesh G. S." , Stefan Hajnoczi Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" John Snow writes: > On 6/8/21 11:01 AM, Markus Armbruster wrote: >> John Snow writes: >> [...] >> >>> A challenge will be where to pull the help text from. The QEMU server >>> is not capable (today) of sending help information over the QMP socket >>> itself. >>> >>> We will need to implement a QMP command inside of QEMU directly that >>> is capable of delivering this information to the client so that it can >>> render it. >>> >>> Since not all versions of QEMU will have this feature, the qmp-shell >>> will need to be able to gracefully deal with the lack of help text, >>> displaying an error indicating that this version of QEMU does not have >>> help information compiled into it. >> The doc text is bulky: my bld/docs/manual/interop/qemu-qmp-ref.html >> is >> 1.7 MiB and growing. Less lavish markup results in smaller data. We >> may want to store it compressed, or load it on demand. We might even >> have to make it compile-time optional for some use cases. >> > > ACK, understood. > > raw QAPI directory, including only the json files, is "only" 551.3 kB. > > I assume we can compile help text to something json (or json-like) and > then compress it. Perhaps we could compile something like > qapi-help-introspect.json.tgz and load it on-demand from the QEMU > binary when help text is requested. > > We could prototype under the experimental QMP command x-help, and > limit it to sending help for just one command at a time to limit data > transfer. > > The client could cache the information. (Against what kind of an > identifier? Can QEMU report some kind of token that uniquely > identifies its binary or uniquely identifies the set of QAPI commands > it supports?) I proposed something like it to permit QMP clients cache query-qmp-schema output. Libvirt didn't want it, so it never got beyond the idea stage. > This has the potential to exceed our capacity this summer, but a > prototype experiment might be helpful to inform future work anyway. Beware of the risk that comes with shiny stretch goals: loss of focus. I believe this is actually this GSoC project's main risk.