Re: [netmod] xpath expressions in JSON
Martin Bjorklund <mbj@tail-f.com> Thu, 18 October 2018 10:30 UTC
Return-Path: <mbj@tail-f.com>
X-Original-To: netmod@ietfa.amsl.com
Delivered-To: netmod@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 47F4F12D7F8 for <netmod@ietfa.amsl.com>; Thu, 18 Oct 2018 03:30:44 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.901
X-Spam-Level:
X-Spam-Status: No, score=-1.901 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id HPWLS2y2chh9 for <netmod@ietfa.amsl.com>; Thu, 18 Oct 2018 03:30:40 -0700 (PDT)
Received: from mail.tail-f.com (mail.tail-f.com [46.21.102.45]) by ietfa.amsl.com (Postfix) with ESMTP id 2DDF4130E4D for <netmod@ietf.org>; Thu, 18 Oct 2018 03:30:38 -0700 (PDT)
Received: from localhost (unknown [173.38.220.61]) by mail.tail-f.com (Postfix) with ESMTPSA id 208821AE033A for <netmod@ietf.org>; Thu, 18 Oct 2018 12:30:37 +0200 (CEST)
Date: Thu, 18 Oct 2018 12:30:36 +0200
Message-Id: <20181018.123036.731934458688841323.mbj@tail-f.com>
To: netmod@ietf.org
From: Martin Bjorklund <mbj@tail-f.com>
In-Reply-To: <20181012.103727.731509761734796510.mbj@tail-f.com>
References: <20181011.181150.1840683183107627057.mbj@tail-f.com> <329f67ff-0774-0fd7-f630-7a01c7e7d3be@cisco.com> <20181012.103727.731509761734796510.mbj@tail-f.com>
X-Mailer: Mew version 6.7 on Emacs 24.5 / Mule 6.0 (HANACHIRUSATO)
Mime-Version: 1.0
Content-Type: Text/Plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Archived-At: <https://mailarchive.ietf.org/arch/msg/netmod/bWG-gKKyV4_F28yJ0vr3tUEcI_4>
Subject: Re: [netmod] xpath expressions in JSON
X-BeenThere: netmod@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: NETMOD WG list <netmod.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/netmod>, <mailto:netmod-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/netmod/>
List-Post: <mailto:netmod@ietf.org>
List-Help: <mailto:netmod-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/netmod>, <mailto:netmod-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 18 Oct 2018 10:30:44 -0000
Hi, Going back to the most urgent issue, what is this WG's recommendation for the subscribed-notifications draft in NETCONF wrt/ their usage of yang:xpath1.0 in filters? To summarize: We already have o instance-identifier in XML uses prefixes from the XML document o instance-identifier in JSON uses module names as prefixes o XPath in NETCONF filter uses prefixes from the XML document o XPath in JSON query filter uses module names as prefixes Alternative A: -------------- Use different encodings for "stream-xpath-filter" as well, depending on if it is XML or JSON. We would do in SN: o If the node is encoded in XML, the set of namespace declarations are those in scope on the 'stream-xpath-filter' leaf element. o If the node is encoded in JSON, the set of namespace declarations is the set of prefix and namespace pairs for all supported YANG modules, where the prefix is the YANG module name and the namespace is as defined by the "namespace" statement in the YANG module. Pro: the format is consistent within each encoding. Con: unclear how to handle other encodings. Con: we keep using context-depending encodings. We could probably add that CBOR uses the same representation as JSON. Example in XML: <stream-xpath-filter xmlns:if="urn:ietf:params:xml:ns:yang:ietf-interfaces" xmlns:ip="urn:ietf:params:xml:ns:yang:ietf-ip"> /if:interfaces/if:interface/ip:ipv4 </stream-xpath-filter> Example in JSON: "stream-xpath-filter": "/ietf-interfaces:interfaces/ietf-interfaces:interface/ietf-ip:ipv4" Alternative B: -------------- Use a non-context depending encoding, with the module name as prefix. We would do in SN: o The set of namespace declarations is the set of prefix and namespace pairs for all supported YANG modules, where the prefix is the YANG module name and the namespace is as defined by the "namespace" statement in the YANG module. Pro: the format is independent from the protocol encoding Con: in XML, this leaf is treated differently from other XPath expressions, such as get-config filter and nacm rules. Example in XML: <stream-xpath-filter> /ietf-interfaces:interfaces/ietf-interfaces:interface/ietf-ip:ipv4 </stream-xpath-filter> Example in JSON: "stream-xpath-filter": "/ietf-interfaces:interfaces/ietf-interfaces:interface/ietf-ip:ipv4" My proposal is A. I think it is more important with consistency within each encoding than across encodings. (This said, I would like to have a context-independent encoding of all YANG types in the future. But not now.) /martin
- [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Ladislav Lhotka
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Reshad Rahman (rrahman)
- Re: [netmod] xpath expressions in JSON Andy Bierman
- Re: [netmod] xpath expressions in JSON Qin Wu
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Ladislav Lhotka
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Andy Bierman
- Re: [netmod] xpath expressions in JSON Vladimir Vassilev
- Re: [netmod] xpath expressions in JSON Robert Wilton
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Robert Wilton
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Vladimir Vassilev
- Re: [netmod] xpath expressions in JSON Vladimir Vassilev
- Re: [netmod] xpath expressions in JSON Robert Wilton
- Re: [netmod] xpath expressions in JSON Reshad Rahman (rrahman)
- Re: [netmod] xpath expressions in JSON Robert Wilton
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Andy Bierman
- Re: [netmod] xpath expressions in JSON Robert Wilton
- Re: [netmod] xpath expressions in JSON Andy Bierman
- Re: [netmod] xpath expressions in JSON Reshad Rahman (rrahman)
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Robert Wilton
- Re: [netmod] xpath expressions in JSON Robert Wilton
- Re: [netmod] xpath expressions in JSON Andy Bierman
- Re: [netmod] xpath expressions in JSON Reshad Rahman (rrahman)
- Re: [netmod] xpath expressions in JSON Ladislav Lhotka
- Re: [netmod] xpath expressions in JSON Vladimir Vassilev
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Ladislav Lhotka
- Re: [netmod] xpath expressions in JSON Robert Wilton
- Re: [netmod] xpath expressions in JSON Reshad Rahman (rrahman)
- Re: [netmod] xpath expressions in JSON Vladimir Vassilev
- Re: [netmod] xpath expressions in JSON Andy Bierman
- Re: [netmod] xpath expressions in JSON Juergen Schoenwaelder
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Andy Bierman
- Re: [netmod] xpath expressions in JSON Andy Bierman
- Re: [netmod] xpath expressions in JSON Juergen Schoenwaelder
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Andy Bierman
- Re: [netmod] xpath expressions in JSON Ladislav Lhotka
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Ladislav Lhotka
- Re: [netmod] xpath expressions in JSON Qin Wu
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Ladislav Lhotka
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Ladislav Lhotka
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Robert Wilton
- Re: [netmod] xpath expressions in JSON Ladislav Lhotka
- Re: [netmod] xpath expressions in JSON Juergen Schoenwaelder
- Re: [netmod] xpath expressions in JSON Robert Wilton
- Re: [netmod] xpath expressions in JSON Juergen Schoenwaelder
- Re: [netmod] xpath expressions in JSON Ladislav Lhotka
- Re: [netmod] xpath expressions in JSON Juergen Schoenwaelder
- Re: [netmod] xpath expressions in JSON Martin Bjorklund
- Re: [netmod] xpath expressions in JSON Kent Watsen