What juju charm hooks are available and what does each one do?

Solution 1:

The documentation for all available hooks is available here:

• https://jujucharms.com/docs/stable/authors-charm-hooks

The basic lifecycle (install, start, stop) and relation hooks are documented under charms. Relation hooks are defined for every relation a charm defines in its metadata.

Beyond those there are two other hooks of interest, the 'upgrade-charm' hook, which is called when a service's charm is upgraded for each of its service units.

The other is the 'config-changed' hook, called when a charm which defines a service configuration schema has its configuration changed, since services can be deployed with configuration data, the config-changed hook is also invoked upon the initial deploy of a unit prior to starting it.

all hooks are optional.