New feature in Juju 2.8: Improved actions experience

[timClicks (Tim McNamara)]

Actions provide the ability for charm authors to specify operational tasks that should be able to be run time to time.

In Juju 2.8, a re-design of actions is now available. The major changes are:

• Terminology has been changed. Actions are now composed of “tasks” and “operations”. Actions spawn an operation per application and operations spawn a task per unit.
• Running an action defaults to waiting for the output before returning. This synchronous behaviour allows actions to be easily be included in command-line pipelines. Previously you were required to use juju show-action-output by default.
• Running actions can now be cancelled.
• Charm authors now have the ability to send progress reports (“progress log messages”) to Juju administrators
• Plain text output is now excludes YAML boilerplate. This is intended to make it easier to compose command-line pipelines with actions.
• STDOUT and STDERR are both included in output
• Action identifiers are now numeric integers instead of UUIDs
• The ability to list pending, running, completed actions has been added
• The ability to watch progress of a running action has been added

These points are elaborated on in this post:

Juju Actions: opt-in to new behaviour from Juju 2.8

The UX around Juju Actions has undergone a fairly radical re-design to address some long standing issues and deliver some nice usability improvements. An early version of this was delivered in Juju 2.7. Coming in Juju 2.8 is a more polished iteration. Key points: terminology changes running an action defaults to synchronous (block until done) running actions can be cancelled new ability to display progress log messages cleaner plain text output option stdout and stderr included in output nume…