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Posted to dev@ariatosca.apache.org by DeWayne Filppi <de...@gigaspaces.com> on 2017/07/03 20:01:46 UTC
imperative workflows (1.1)
Is there any current support for imperative workflows (ala 1.1)? If not,
is it a priority roadmap item?
--DeWayne
Re: imperative workflows (1.1)
Posted by Tal Liron <ta...@gigaspaces.com>.
Hi Steve,
Let's just call it ARIA (the "ng" next-gen suffix was a temporary
development code, no longer necessary as everything is merged into the
Apache repository).
The Python workflow function doesn't actually execute the operations. Its
job is to create the workflow graph based on the topology. The graph is a
series of interdependent tasks that usually just execute a TOSCA operation
on an interface of a node, a relationship, or a group. For example, the
normative TOSCA "install" workflow has a series of interdependent
operations to install, configure, and start nodes and operations, based on
the TOSCA normative lifecycle interfaces. (See the TOSCA spec for more
details.) Your own custom workflows will likely use your own custom
interfaces and operation with their own define dependencies. That's where
you need Python to build that graph. Actually, most workflow functions are
quite short: there's not a lot of Python to write here.
Once the workflow Python function creates the graph, an "executor" actually
handles the execution of the tasks. ARIA's built-in executor can run the
tasks either locally (on the machine running ARIA) or remotely via SSH, and
expects these "implementations" to be be simple executable artifacts, such
as shell scripts, that can be included in the CSAR. That's all standard
TOSCA behavior. The executor API, though, is extensible and we expect many
useful executors in the future. We have some support for Celery, and will
also expect Puppet, Chef, and Juju. So a task, for example, could execute a
Juju charm rather than just run a shell script. All of these products have
their own rich debugging tools.
That said, We've also put a lot of effort into the logging mechanism: logs
are stores in the database (SQL), and are marked per workflow execution and
per service, so even if you are running a large number of workflows you can
still pinpoint the error without rummaging through mountains of text logs.
The CLI lets you access these logs, though you can read the database via
your own monitoring and analytics tools. So, if an individual task fails,
the error message will be logged at this high level.
It's also worth pointing out that even the task API is extensible. Though
usually you want to execute TOSCA operations as part of your workflow, you
can include your own custom tasks as part of the workflow, for
domain-specific operations that are just not relevant to the TOSCA
topology. (For example, a task to discover a controller, register a
transaction, etc.)
The CLI is quite rich in other aspects, including tools to display the
topology in depth and understand what might have gone wrong.
Obviously, this is an ongoing effort and we would very much appreciate
feedback on how to improve debugging and workflow construction. Of course
we look forward to TOSCA 1.1 finalizing and allowing a way to define these
workflow graphs in YAML, although from experience we expect that YAML might
not be good enough for some especially complex workflows. But, we'll wait
and see, TOSCA 1.1 is also an ongoing effort.
We're also missing a guide and examples for how to do all this. For now, we
are here to help on the mailing list!
On Tue, Jul 4, 2017 at 5:54 PM, Steve Baillargeon <
steve.baillargeon@ericsson.com> wrote:
> Hi
> Good information.
> How does the user troubleshoot a Python script that is not properly
> executed by ARIA NG?
> Any support for CLI or API to inform client and provide cause/reason for
> error?
>
> -Steve B
>
> -----Original Message-----
> From: Ran Ziv [mailto:ran@gigaspaces.com]
> Sent: Tuesday, July 04, 2017 4:23 AM
> To: dev@ariatosca.incubator.apache.org
> Subject: Re: imperative workflows (1.1)
>
> Yup. We have given some thought as to how to implement 1.1 workflows
> including conditional tasks ("on_success"/"on_failure") and it maps well
> into the workflow engine, but generally speaking supporting TOSCA 1.1 is
> not currently a top item.
>
> On Tue, Jul 4, 2017 at 8:12 AM, Tal Liron <ta...@gigaspaces.com> wrote:
>
> > Not exactly. We do not support TOSCA 1.1 imperative workflows and it's
> > not on the roadmap. Our current plan is to provide a state-of-the-art
> > TOSCA 1.0 implementation, and we're not at 100% completion yet.
> >
> > That said, we support something we call "custom workflows". They are
> > not defined directly in TOSCA, but rather in a Python function
> > indicated by a TOSCA policy (of type aria.Workflow).
> >
> > To be honest, you can do a lot more with Python than with TOSCA, but
> > of course we understand that Python is not an option for many users.
> > And of course this is an optional feature.
> >
> > Bottom line: we do not support TOSCA 1.1 right now, but have a very
> > powerful workaround.
> >
> > On Mon, Jul 3, 2017 at 3:01 PM, DeWayne Filppi
> > <de...@gigaspaces.com>
> > wrote:
> >
> > > Is there any current support for imperative workflows (ala 1.1)? If
> > > not, is it a priority roadmap item?
> > >
> > > --DeWayne
> > >
> >
> >
> >
> > --
> > Tal Liron, Senior Solutions Architect <http://cloudify.co>
> > ------------------------------
> > M: +1-312-375-8299 http://cloudify.co @cloudifysource
> > <https://twitter.com/CloudifySource>
> > <https://www.linkedin.com/company-beta/17918192/>
> > <https://github.com/cloudify-cosmo>
> > <https://www.youtube.com/cloudifysource>
> >
>
--
Tal Liron, Senior Solutions Architect <http://cloudify.co>
------------------------------
M: +1-312-375-8299 http://cloudify.co @cloudifysource
<https://twitter.com/CloudifySource>
<https://www.linkedin.com/company-beta/17918192/>
<https://github.com/cloudify-cosmo>
<https://www.youtube.com/cloudifysource>
RE: imperative workflows (1.1)
Posted by Steve Baillargeon <st...@ericsson.com>.
Hi
Good information.
How does the user troubleshoot a Python script that is not properly executed by ARIA NG?
Any support for CLI or API to inform client and provide cause/reason for error?
-Steve B
-----Original Message-----
From: Ran Ziv [mailto:ran@gigaspaces.com]
Sent: Tuesday, July 04, 2017 4:23 AM
To: dev@ariatosca.incubator.apache.org
Subject: Re: imperative workflows (1.1)
Yup. We have given some thought as to how to implement 1.1 workflows including conditional tasks ("on_success"/"on_failure") and it maps well into the workflow engine, but generally speaking supporting TOSCA 1.1 is not currently a top item.
On Tue, Jul 4, 2017 at 8:12 AM, Tal Liron <ta...@gigaspaces.com> wrote:
> Not exactly. We do not support TOSCA 1.1 imperative workflows and it's
> not on the roadmap. Our current plan is to provide a state-of-the-art
> TOSCA 1.0 implementation, and we're not at 100% completion yet.
>
> That said, we support something we call "custom workflows". They are
> not defined directly in TOSCA, but rather in a Python function
> indicated by a TOSCA policy (of type aria.Workflow).
>
> To be honest, you can do a lot more with Python than with TOSCA, but
> of course we understand that Python is not an option for many users.
> And of course this is an optional feature.
>
> Bottom line: we do not support TOSCA 1.1 right now, but have a very
> powerful workaround.
>
> On Mon, Jul 3, 2017 at 3:01 PM, DeWayne Filppi
> <de...@gigaspaces.com>
> wrote:
>
> > Is there any current support for imperative workflows (ala 1.1)? If
> > not, is it a priority roadmap item?
> >
> > --DeWayne
> >
>
>
>
> --
> Tal Liron, Senior Solutions Architect <http://cloudify.co>
> ------------------------------
> M: +1-312-375-8299 http://cloudify.co @cloudifysource
> <https://twitter.com/CloudifySource>
> <https://www.linkedin.com/company-beta/17918192/>
> <https://github.com/cloudify-cosmo>
> <https://www.youtube.com/cloudifysource>
>
Re: imperative workflows (1.1)
Posted by Ran Ziv <ra...@gigaspaces.com>.
Yup. We have given some thought as to how to implement 1.1 workflows
including conditional tasks ("on_success"/"on_failure") and it maps well
into the workflow engine, but generally speaking supporting TOSCA 1.1 is
not currently a top item.
On Tue, Jul 4, 2017 at 8:12 AM, Tal Liron <ta...@gigaspaces.com> wrote:
> Not exactly. We do not support TOSCA 1.1 imperative workflows and it's not
> on the roadmap. Our current plan is to provide a state-of-the-art TOSCA 1.0
> implementation, and we're not at 100% completion yet.
>
> That said, we support something we call "custom workflows". They are not
> defined directly in TOSCA, but rather in a Python function indicated by a
> TOSCA policy (of type aria.Workflow).
>
> To be honest, you can do a lot more with Python than with TOSCA, but of
> course we understand that Python is not an option for many users. And of
> course this is an optional feature.
>
> Bottom line: we do not support TOSCA 1.1 right now, but have a very
> powerful workaround.
>
> On Mon, Jul 3, 2017 at 3:01 PM, DeWayne Filppi <de...@gigaspaces.com>
> wrote:
>
> > Is there any current support for imperative workflows (ala 1.1)? If not,
> > is it a priority roadmap item?
> >
> > --DeWayne
> >
>
>
>
> --
> Tal Liron, Senior Solutions Architect <http://cloudify.co>
> ------------------------------
> M: +1-312-375-8299 http://cloudify.co @cloudifysource
> <https://twitter.com/CloudifySource>
> <https://www.linkedin.com/company-beta/17918192/>
> <https://github.com/cloudify-cosmo>
> <https://www.youtube.com/cloudifysource>
>
Re: imperative workflows (1.1)
Posted by Tal Liron <ta...@gigaspaces.com>.
Not exactly. We do not support TOSCA 1.1 imperative workflows and it's not
on the roadmap. Our current plan is to provide a state-of-the-art TOSCA 1.0
implementation, and we're not at 100% completion yet.
That said, we support something we call "custom workflows". They are not
defined directly in TOSCA, but rather in a Python function indicated by a
TOSCA policy (of type aria.Workflow).
To be honest, you can do a lot more with Python than with TOSCA, but of
course we understand that Python is not an option for many users. And of
course this is an optional feature.
Bottom line: we do not support TOSCA 1.1 right now, but have a very
powerful workaround.
On Mon, Jul 3, 2017 at 3:01 PM, DeWayne Filppi <de...@gigaspaces.com>
wrote:
> Is there any current support for imperative workflows (ala 1.1)? If not,
> is it a priority roadmap item?
>
> --DeWayne
>
--
Tal Liron, Senior Solutions Architect <http://cloudify.co>
------------------------------
M: +1-312-375-8299 http://cloudify.co @cloudifysource
<https://twitter.com/CloudifySource>
<https://www.linkedin.com/company-beta/17918192/>
<https://github.com/cloudify-cosmo>
<https://www.youtube.com/cloudifysource>