Open Stack

On 11/14/2013 08:32 AM, George Reese wrote:
> One critical reasons why tasks rather than resource status may be
> required is because:
>
> a) The system state may not be sufficient at time of POST/PUT to
> generate a “minimum viable resource” and we don’t want to risk timeouts
> waiting for the “minimum viable resource"
> b) There may be more stuff about the workflow worth tracking beyond
> simple status, including the ability to act on the workflow

Agreed.

<snip>

> Also, as a side note, I think there should be a separate, shared tasks
> tracking component (ooh, something new for “OpenStack core” :)) that is
> the central authority on all task management. Glance (and Nova and
> everyone else) would interact with this component to create and update
> task status, but clients would query against it. It would also have it’s
> own API.
>
> That way, a client subsystem could be handed a random task from an
> arbitrary OpenStack component and easily know the semantics for getting
> information about it.

There are two related projects in this space so far. Taskflow [1] is a 
library that aims to add structure to the in-process management of 
related tasks. Mistral [2] is a project that aims to provide a 
distributed task scheduling service that may act as the external 
subsystem/proxy you describe above.

Both are under heavy development and my hope is that both projects 
continue to evolve in their distinct ways and offer other OpenStack/open 
source projects different functionalities.

Best,
-jay

[1] https://wiki.openstack.org/wiki/TaskFlow
[2] https://wiki.openstack.org/wiki/Mistral