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=-5.0 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 76DEBC433E0 for ; Mon, 22 Feb 2021 17:57:20 +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 17E22601FF for ; Mon, 22 Feb 2021 17:57:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 17E22601FF 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]:54626 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lEFSR-0001Tk-5j for qemu-devel@archiver.kernel.org; Mon, 22 Feb 2021 12:57:19 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:55976) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lEFQN-0007MG-FX for qemu-devel@nongnu.org; Mon, 22 Feb 2021 12:55:11 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:60866) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1lEFQL-0002rY-GL for qemu-devel@nongnu.org; Mon, 22 Feb 2021 12:55:11 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1614016508; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=06ocIJYingTe08czhNxdk81G+KYrQyIhvOHB3pyXNQg=; b=L/AFi9Rhm0K8j/grasR20PSLcCOX9J37pg0zd22lwn4Hjaqk6GVPk+vCFk/XYEajZ8M+lh 87Iqtbbovf5vj865W1a4Xvn2m4lFAQNyE5Y6FK8cQNMH1jRJjApgNNE6PqiaFqKZb4HTcu jCmVhCcRSz6k+cLetEIr+lBRBP98bCM= 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-62-weCI84jWO4ykedT7YswcEw-1; Mon, 22 Feb 2021 12:55:02 -0500 X-MC-Unique: weCI84jWO4ykedT7YswcEw-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 459A780402E; Mon, 22 Feb 2021 17:55:01 +0000 (UTC) Received: from redhat.com (ovpn-115-70.ams2.redhat.com [10.36.115.70]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D6FC45C260; Mon, 22 Feb 2021 17:54:54 +0000 (UTC) Date: Mon, 22 Feb 2021 17:54:52 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Paolo Bonzini Subject: Re: A brief look at deprecating our JSON extensions over RFC 8259 Message-ID: References: <875z2knoa5.fsf@dusky.pond.sub.org> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/2.0.5 (2021-01-21) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=berrange@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: libvir-list@redhat.com, Peter Maydell , John Snow , Markus Armbruster , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, Feb 22, 2021 at 06:47:30PM +0100, Paolo Bonzini wrote: > On 22/02/21 16:24, Daniel P. Berrangé wrote: > > This problem isn't unique to QEMU. Any app using JSON from the > > shell will have the tedium of quote escaping. JSON is incredibly > > widespread and no other apps felt it neccessary to introduce single > > quoting support, because the benefit doesn't outweigh the interop > > problem it introduces. > > The quotes were introduced for C code (and especially qtest), not for the > shell. We have something like > > response = qmp("{ 'execute': 'qom-get', 'arguments': { 'path': %s, " > "'property': 'temperature' } }", id); > > These are sent to QEMU as double-quoted strings (the single-quoted JSON is > parsed to get interpolation and printed back; commit 563890c7c7, "libqtest: > escape strings in QMP commands, fix leak", 2014-07-01). However, doing the > interpolation requires a parser that recognizes the single-quoted strings. IMHO this is the wrong solution to the problem. Consider the equivalent libvirt code that uses a standard JSON library underneath and has a high level API to serialize args into the command qemuMonitorJSONMakeCommand("qom-get", "s:path", id, "s:property", "temperature"); Of course this example is reasonably easy since it is a flat set of arguments. Nested args get slightly more complicated, but still always preferrable to doing string interpolation IMHO. Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|