grenade/PLUGINS.rst

Modular Grenade Architecture

Grenade was originally created to demonstrate some level of upgrade capacity for OpenStack projects. Orginally this just included a small number of services.

Proposed new basic flow:

• setup_grenade
  • all the magic setup involved around err traps and filehandle redirects
  • setup devstack trees
• setup_base
  • run stack.sh to build the correct base environment
• verify_base
  • for project in projects; do verify_project; done
• resources-create
• shutdown
  • for project in projects; do shutdown; done
• snapshot.sh pre_upgrade
• resources-survive-shutdown
• upgrade ...
• resources-survive-upgrade
• verify_target
• resources_cleanup

Modular Components

Assuming the following tree in target projects:

devstack/    - devstack plugin directory
   upgrade/   - upgrade scripts
       settings   - adds settings for the upgrade path
       upgrade.sh
       snapshot.sh - snapshots the state of the service, typically a
          database dump
       from-juno/ - per release
       within-juno/
       from-kilo/
       within-kilo/
       resources.sh
       verify.sh

This same modular structure exists in the grenade tree with::

grenade/

projects/

10_ceilometer/

settings upgrade.sh

resources.sh

This is a script that's designed to be called in the following ways:

• resources.sh create

  creates a set of sample resources that should survice upgrade. Script should exit with a non zero exit code if any resources could not be created.

• resources.sh survived_shutdown

  resource survival checks for after all services are shut down (the in between phase for upgrades). Script should exit with a non zero exit code if any resources were detected as offline.

• resources.sh survived_upgrade

  resource survival checks for after all services are started on the new code revisions. Script should exit with a non zero exit code if any resources no longer exist after the upgrade.

• resources.sh cleanup

  cleanup all resources

In order to assist with the checks listed the following functions exist:

resource_data_add project key value
resource_data_get project key