Hi Luc,
Please see my inline comments.
Thanks,
Huabing
Hi Huabing,
I realized you made your own choices out of the TC and really want them to be standard now.
Huabing: I didn't mea that(make my own choices), It's the intention of broader audience/users of TOSCA (Service Provider:AT&T, CMCC, Vendor:Huawei, ZTE and research group:University of Stuttgart) to keep BPMN/BPEL in TOSCA, based on their own experiences and requirements, I think we all have heard their concerns in the proposal presentation and open comments maillist. Also I thought it's the conclusion of the last meeting that I've confirmed by mails.
You are talking a lot about scenarios that cannot be done with current TOSCA but I still don’t see them to be honest. I think that current workflow + artifact types/artifact type executors can do everything, even manual operations as you can make an artifact type/artifact type executor that will prompt user. It’s just that it follows a TOSCA compliant way to do so, and compliant in 2 ways:
- Can be triggered through imperative workflows
- Can be included in a declarative generated workflow (this is critical as this is kind of the goal of TOSCA).
BPMN taks are not defined on TOSCA nodes and cannot be triggered through declarative generated workflows. This is again why it’s not a good target for TOSCA and for what we try to achieve.
it's not the main goal of orchestration.
You asked for better choice we already provided one:
- artifact type approach is absolutely valid and allow to have both portability kept and BPMN execution possible, so this is to me the better approach that we BTW agreed on on the calls. Not sure you understood what I write in my previous email but I feel that delegate or artifact type are quite the same thing here.
And no, I’m not in favour of losing portability again, and to be honest not in favour of supporting any workflow languages as long as we don’t have a way to make it portable (I mean internally do what you want and as I explained already you can use internally a BPMN engine to process your TOSCA, that is your choice).
I think that TOSCA exists for quite a long time now and we didn’t had really portability, right now every implementer made their own choices (that’s what you did, that’s what GigaSpaces did, that’s also what we did in our tool – for the yet not fully standardize custom artifact executions). Based on that I feel that there is 2 path for TOSCA:
- Stop trying to solve the execution issue and be just a modelling language (drop interfaces and operations) and let people provide imperative specific means to make things executed through other specs (BPMN etc.) or other means (Docker compose, Kubernetes models or other declarative approaches that comes).
- Keep trying to address the initial challenge which is to try to build a portable declarative and executable standard (well that’s quick sentence but I think it was the main points of TOSCA somehow).
So I’m sorry but no I cannot kindly agree with something that I really feels as a wrong path. That said if I’m the only one to feel that way please let me know as we should probably stop a lot of work we started here (including artifact type executor and let people just do their own custom non portable things).
Luc
From: "zhao.huabing@zte.com.cn" ＜zhao.huabing@zte.com.cn＞
Date: Monday, 27 March 2017 at 04:44
To: Luc Boutier ＜luc.boutier@fastconnect.fr＞
Cc: Chris Lauwers ＜lauwers@ubicity.com＞, Matthew Rutkowski ＜mrutkows@us.ibm.com＞, "tosca@lists.oasis-open.org" ＜tosca@lists.oasis-open.org＞, "claude.noshpitz@att.com" ＜claude.noshpitz@att.com＞, Paul Lipton ＜paul.lipton@ca.com＞, shitao li ＜lishitao@huawei.com＞, "meng.zhaoxing1@zte.com.cn" ＜meng.zhaoxing1@zte.com.cn＞
Subject: Re: [tosca] Re:[tosca] RE: Re:[tosca] Groups - Issue_TOSCA318_Lack of BPMN BPEL support-v1.0.pptx uploaded
Hi Luc,
I think Chirs' suggestion make sense.
Just like a famous western saying: "Rome wasn't built in a day", it's not realistic to try to work out a "perfect" solution overnight. We need to solve the issue we currently faced and allow it evolve towards the right direction in the same time. I'd like to say that there might be a solution close to but not "perfect" solution at all, becasue things always change.
Furthermore, I don't think exclusive approach is the best choice for workflow. Because there is no a silver bullet to solve all the problems. Just as what I and Claud were saying in the last proposal presentation, there were still some scenarios which tosca workflow can't handle with right now, which have already been implemented by BPMN/BPEL in OpenECOMP/OPEN-O/OpenTOSCA.
I will be appreciate if you could kindly agree this approach or you can figure out a better one to address it in a short term.
Thanks,
Huabing
Original Mail
Sender: ＜luc.boutier@fastconnect.fr＞;
To: ＜lauwers@ubicity.com＞;zhaohuabing10201488;
CC: ＜mrutkows@us.ibm.com＞; ＜tosca@lists.oasis-open.org＞; ＜claude.noshpitz@att.com＞; ＜paul.lipton@ca.com＞; ＜lishitao@huawei.com＞;MengZhaoXing10024238;
Date: 2017/03/25 04:35
Subject: Re: [tosca] Re:[tosca] RE: Re:[tosca] Groups - Issue_TOSCA318_Lack of BPMN BPEL support-v1.0.pptx uploaded
Hi Chris,
I see no real difference with this delegate proposal and an operation within the workflow except that operation with artifact type is something we are working on and could provide portable and normative support.
We can write a TOSCA 1.1 workflow with set_state at the end and a single call to the BPMN artifact operation, that is really similar to what you propose but leveraging planned 1.2 standard definitions (once we finish the artifact type and artifact executor definition). If not we will end up with a delegate that orchestrator does not know how to handle, delegate is intended for orchestrator provided nodes (matched abstract nodes – so specific to orchestrator). Or only some specific impl will know how to handle them? And this will be custom per Impl and for no more benefits that the simple artifact support that we proposed.
Once again, I really think that we should work on instance model and API before we go further. And also complete the work on custom artifact type support because even this is not fully completed yet and seems on hold since we discuss this BPMN/BPEL elements rather moving forward. I really believe that more than making some people happy we should focus on trying to build a reliable standard. This is exactly why we worked on the workflow spec in 1.1. because there where nothing people could really rely on in previous spec. Declarative workflows ordering was not clearly defined and saying that multiple workflows languages could be consider was not a reliable statement and actually just lead us to the point we are now with people making their own choices out of the TC and trying to find a reconciliation rather than moving forward on the multiple challenges we should address.
I think that in this perspective the work started on artifact type support is critical and we should complete that work rather than trying to solve all issues and especially elements that will not bring more to TOSCA but just please people (I am still not seeing anything that is TOSCA compliant that cannot be done with the actual workflow language – and not TOSCA compliant elements should currently be supported through specific artifacts). I still feel on my own that other workflows language will weaken TOSCA as they are not compliant with the TOSCA way to define and call operations and especially the current artifact type work.
That said I don’t say we should not consider the support of specific workflow languages in the future, I just feel that we should not make wrong choices to please people while some elements are not ready yet in TOSCA.
Anyway, we just don’t agree here I guess,
Luc
From: Chris Lauwers ＜lauwers@ubicity.com＞
Date: Friday, 24 March 2017 at 18:29
To: Luc Boutier ＜luc.boutier@fastconnect.fr＞, "zhao.huabing@zte.com.cn" ＜zhao.huabing@zte.com.cn＞
Cc: Matthew Rutkowski ＜mrutkows@us.ibm.com＞, "tosca@lists..oasis-open..org" ＜tosca@lists.oasis-open.org＞, "claude.noshpitz@att.com" ＜claude.noshpitz@att.com＞, Paul Lipton ＜paul.lipton@ca.com＞, shitao li ＜lishitao@huawei.com＞, "meng.zhaoxing1@zte.com.cn" ＜meng.zhaoxing1@zte.com.cn＞
Subject: RE: [tosca] Re:[tosca] RE: Re:[tosca] Groups - Issue_TOSCA318_Lack of BPMN BPEL support-v1.0.pptx uploaded
Hi Luc,
While I generally agree with the “walk before you run” approach, I believe there might be a very simple way to accommodate what Huabing wants. How about the following:
1. We already have a “delegate” keyname on workflow activities. What if in addition, we also allowed a “delegate” keyname on a top-level workflow definition? This would signal to the orchestrator (in a standardized way) that the workflow would be taken over entirely by an external entity. The argument of the “delegate” keyname would be the artifact name of the BPNM or BPEL workflow (for which we would obviously still need to define a processor).
2. I also agree that in order to do this correctly, we will have to standardize an API to the instance model, and more sophisticated TOSCA workflows could benefit from such an API as well. However, the API available to TOSCA workflows today is limited to “set_state” and “call_operation”. At the very least, we could make those operations available to external workflows, which would put these external workflows on-par with TOSCA workflows.
While this doesn’t entirely address your “portability” concerns, at least it provides a standard way for template designers to signal to the orchestrator that responsibility for orchestration needs to be delegated to an external workflow engine.
thanks,
Chris
From: BOUTIER, LUC [mailto:luc.boutier@fastconnect.fr]
Sent: Wednesday, March 22, 2017 11:31 PM
To: Chris Lauwers ＜lauwers@ubicity.com＞; zhao.huabing@zte.com.cn
Cc: mrutkows@us..ibm.com; tosca@lists.oasis-open.org; claude.noshpitz@att.com; paul.lipton@ca.com; lishitao@huawei.com; meng.zhaoxing1@zte.com.cn
Subject: Re: [tosca] Re:[tosca] RE: Re:[tosca] Groups - Issue_TOSCA318_Lack of BPMN BPEL support-v1.0.pptx uploaded
Chris, Huabing,
I think that we should not constraint 1.2 on custom workflow support and that we should try to go step by step:
1. We still don’t have artifact type executors completed and I think this is the first step we need to complete
2. We still don’t have an instance model
3. And once instance model is defined we will need also an instance model API to be defined and agreed
Instance model and Instance model APIs are pre-requisite for any kind of workflow extensions are workflow execution extensions will mean workflow engines external to the TOSCA orchestrator, or there won’t be portability as we cannot expect or have as a pre-requisite for TOSCA orchestrator to support any kind of Workflow languages especially open workflow languages supporting extensions (meaning not supported everywhere).
So, my suggestion is that the 1.2 target should define a way to execute custom operation types in a portable way and we need to have this work completed (this is the great work started by Chris). BPMN or BPEL in 1.2 will be artifact types with the limitations Chris mentioned.
As we say in France « Il ne faut pas mettre la charrue avant les bœufs »
Luc
From: ＜tosca@lists..oasis-open.org＞ on behalf of Chris Lauwers ＜lauwers@ubicity.com＞
Date: Thursday, 23 March 2017 at 05:58
To: "zhao.huabing@zte.com.cn" ＜zhao.huabing@zte.com.cn＞
Cc: Matthew Rutkowski ＜mrutkows@us.ibm.com＞, "tosca@lists.oasis-open.org" ＜tosca@lists.oasis-open.org＞, "claude.noshpitz@att.com" ＜claude.noshpitz@att.com＞, Paul Lipton ＜paul.lipton@ca.com＞, shitao li ＜lishitao@huawei.com＞, "meng..zhaoxing1@zte.com.cn" ＜meng.zhaoxing1@zte.com.cn＞
Subject: RE: [tosca] Re:[tosca] RE: Re:[tosca] Groups - Issue_TOSCA318_Lack of BPMN BPEL support-v1.0.pptx uploaded
I’m not sure about the timeframe. Matt should chime in on this.
Thanks,
Chris
From: tosca@lists.oasis-open.org [mailto:tosca@lists.oasis-open.org] On Behalf Of zhao.huabing@zte.com.cn
Sent: Wednesday, March 22, 2017 9:57 PM
To: Chris Lauwers ＜lauwers@ubicity.com＞
Cc: mrutkows@us.ibm.com; tosca@lists.oasis-open.org; claude.noshpitz@att.com; paul.lipton@ca.com; lishitao@huawei.com; meng.zhaoxing1@zte.com.cn
Subject: [tosca] Re:[tosca] RE: Re:[tosca] Groups - Issue_TOSCA318_Lack of BPMN BPEL support-v1.0.pptx uploaded
Hi Chris,
Thanks for your explanation.
That's exactly what I'm curious about.
So we're planing planning to add arbitrary artifact implementations for the entire workflow of the topology template in 1.2, such as BPMN, BPEL, Node-RED,Ballerina etc.?
Thanks,
Huabing
Original Mail
Sender: ＜lauwers@ubicity.com＞;
To: zhaohuabing10201488; ＜mrutkows@us.ibm.com＞;
CC: ＜tosca@lists.oasis-open.org＞; ＜claude.noshpitz@att.com＞; ＜paul.lipton@ca.com＞; ＜lishitao@huawei.com＞;MengZhaoXing10024238;
Date: 2017/03/23 12:21
Subject: [tosca] RE: Re:[tosca] Groups - Issue_TOSCA318_Lack of BPMN BPEL support-v1.0.pptx uploaded
Hi Huabing,
Yes, your understanding of the plan is correct.
However, in the current version of the spec, artifacts can only be used to provide implementations for operations. For example, this means that you will be able to specify a BPEL workflow to implement the “create” operation on the Standard lifecycle operation.
We currently don’t have a mechanism to use artifacts as implementations for entire workflows. This will need to get added in a later version.
Thanks,
Chris
From: zhao.huabing@zte.com.cn [mailto:zhao.huabing@zte.com.cn]
Sent: Tuesday, March 21, 2017 4:41 AM
To: mrutkows@us.ibm.com; Chris Lauwers ＜lauwers@ubicity.com＞
Cc: tosca@lists.oasis-open.org; claude.noshpitz@att.com; paul.lipton@ca.com; lishitao@huawei.com; meng.zhaoxing1@zte.com.cn
Subject: Re:[tosca] Groups - Issue_TOSCA318_Lack of BPMN BPEL support-v1.0.pptx uploaded
Hi Matt, Chris,
I haven't find any update about this in my inbox, did I miss anything?
I guess the idea is that TOSCA could take BPMN/BPEL as an artifact type and it can be executed by an artifact processor(workflow execution engine) provided by orchestrator, right?
Thanks,
Huabing
Original Mail
Sender: zhaohuabing10201488
To: ＜mrutkows@us.ibm.com＞; ＜lauwers@ubicity.com＞;
CC: ＜tosca@lists.oasis-open.org＞; ＜claude.noshpitz@att.com＞; ＜paul.lipton@ca.com＞; ＜lishitao@huawei.com＞;MengZhaoXing10024238;
Date: 2017/03/16 09:54
Subject: Re:[tosca] Groups - Issue_TOSCA318_Lack of BPMN BPEL support-v1.0.pptx uploaded
Hi Matt,
Thanks for uploading the slide deck.
Do we have a minutes for this meeting? I'm still improving my English skill, so I have difficulty to get all the points of everyone in this meeting...
Is the conclusion that we'll incorporate BPMN/BPEL workflow as artifact in the later version of simple YAML and Chris are working on that?
Thanks,
Huabing
Sender: ＜mrutkows@us.ibm.com＞;
To: ＜tosca@lists.oasis-open.org＞;
Date: 2017/03/15 23:16
Subject: [tosca] Groups - Issue_TOSCA318_Lack of BPMN BPEL support-v1.0.pptx uploaded
Submitter's message
Parts of these slides were presented during the 2017-03-14 Simple Profile WG meeting.
-- Mr. Matthew Rutkowski
Document Name: Issue_TOSCA318_Lack of BPMN BPEL support-v1.0.pptx No description provided... Submitter: Mr. Matthew Rutkowski |