image management 3.4 spec workflow declaration

Table of Contents Workflow Declaration Ansible RegisterImage EC2 Service Imaging Service Import Instance EC2 Service Imaging Service Test Plan

Workflow Declaration

There are a number of workflows which interact with the image management services and tools. Some of them are currently supported by other functionality in Eucalyptus which will be superceded by image management services/tools and will be deprecated. The important workflows are:

RegisterImage: an existing workflow which will change.
BundleInstance: an existing workflow which will change.
CreateImage: potentially a new workflow.
ImportInstance: a new workflow.
ImportVolume: a new workflow.

Ansible

A quick investigation indicates that it may be possible to express the orchestration of the image toolkit operations as an ansible playbook. That is, it has the following attributes:

Install/Depends: Small and standard set of dependencies (yaml and jinja2)
Playbook/Task Composition:
1. Conditional execution can be used to execute playbook tasks based on either input parameters or computed values (e.g., to scope tasks to the right input image types).
2. Conditional imports can be used to compose the workflow playbooks.
3. parameterizable and included tasks
4. nested playbooks
Execution State Information:
1. Descriptive declaration of tasks
2. A Dry Run execution mode
3. Asynchronous Tasks and access to Asynchronous Task State
4. Additional instrumentation of playbook execution through callbacks Ansible Callback Plugins
Execution Environments:
1. NOTE: ssh to a host is the standard behaviour
2. Support for Local Playbook execution mode
3. Operating in a chroot (verified present in the 1.2 release; which is current)
AWS service support:
1. Support for EC2 (can run instances)
2. Support for S3 (only for testing existence of objects)