Topology and Orchestration Specification for Cloud Applications (TOSCA) and Juju

[Johannes Wettinger]

Hi there,

I'm currently doing some research and prototype implementation in the
field of Cloud standards. In particular, my work is strongly related
to an upcoming standard called "Topology and Orchestration
Specification for Cloud Applications" (TOSCA):
http://www.tosca-open.org

Now I came across Juju and I recognized that some concepts behind Juju
are quite similar to TOSCA. Of course, TOSCA is much more complex
because of its highly generic approach to describe service models.
Just wondering if anyone here is familiar with TOSCA, too?

What is your opinion of bringing these two worlds (TOSCA and Juju)
together? I mean wouldn't it make a lot of sense to support TOSCA
service templates in Juju? As an example, node types in TOSCA are
basically very similar to Juju's charms and lifecycle operations
including their implementation artifacts in TOSCA are quite similar to
hooks in Juju. :-)

A node type definition for an Apache web server could look like this:

<NodeType id="apache-server" name="Apache Web Server">
  <Interfaces>
    <Interface name="LifecycleInterface">
      <Operation name="install">
        <ScriptOperation/>
      </Operation>
      <ImplementationArtifacts>
        <ImplementationArtifact operationName="install"
              type="http://www.example.com/ScriptArtifact/PhythonReference">
          scripts/install-apache.py
        </ImplementationArtifact>
      </ImplementationArtifacts>
    </Interface>
  </Interfaces>
</NodeType>


Such a node type can also be rendered as JSON or YAML. So, please
don't be confused about the XML snippet. :-)

Looking forward to reading your comments.

Cheers
Johannes