Open Stack

On 22/02/14 03:37, Stan Lagun wrote:
> Hi Everyone,
>
> While looking through Heat templates generation code in Murano I've
> realized it has a major design flaw: there is no isolation between
> Heat resources generated by different apps.
>
> Every app manifest can access and modify its environment stack in any
> way. For example it can delete instances and other resources belonging
> to other applications. This may be not so bad for Murano 0.4 but it
> becomes critical for AppCatalog (0.5) as there is no trust relations
> between applications and it may be unacceptable that untrusted
> application can gain complete write access over the whole stack.
>
> There is also a problem of name collisions - resources generated by
> different applications may have the same names. This is especially
> probable between resources generated by different instances of the
> same app. This also affects Parameters/Output of Heat templates as
> each application instance must generate unique names for them (and do
> not forget them later as they are needed to read output results).
>
> I think we need at least to know how we going to solve it before 0.5
>
> Here is possible directions i can think of:
>
> 1. Use nested Heat stacks. I'm not sure it solves naming collisions
> and that nested stacks can have their own Output
>
> 2. Control all stack template modifications and track which resource
> was created by which app. Give applications read-only access to
> resources they don't own
>
> 3. Auto-generate resource names. Auto-add prefixes/suffixes to
> resource/output etc names indicating owning app instance ID and remove
> them upon read access from workflow so that generated names would be
> invisible to workflow. That would also mean all VMs  would have
> generated names
>
> Hope to see better ideas and suggestions in this thread
>
I would like the Murano project to evaluate the upcoming heat
software-config resources to represent app configuration.
Some patches are still in review [1][2] and I expect more changes before
feature freeze, but now would be a good time for Murano to get involved
to validate that software-config meets your needs.

The current implementation of the SoftwareDeployment resource actually
has the same issue mentioned above; any authenticated user can currently
create a deployment which results in software being deployed to any
server in that tenant/project. There may be times where this is useful,
but there will soon be a default policy enforced which ensures that the
deployment resource and the server resource belong to the same stack.

Inferring from the above, it sounds like Murano is transforming an app
definition into a single flat heat template. Using a combination of
resource providers and software config should give you a significantly
cleaner model, and you may even find that some of the problems you're
solving in Murano are now solved in the Heat layer.

[1]
https://review.openstack.org/#/q/status:open+topic:bp/hot-software-config-rest,n,z
[2]
https://review.openstack.org/#/q/status:open+topic:bp/hot-software-config,n,z