def when(*desired_states):
"""
Register the decorated function to run when all ``desired_states`` are active.
If a state is associated with a relation, an instance of that relation
class will be passed in to the decorated function.
This can be used from Bash using the ``reactive.sh`` helpers::
source `which reactive.sh`
when db.ready cache.ready; then
db_dsn=$(state_relation_call db.ready uri)
cache_uri=$(state_relation_call cache.ready uri)
chlp render_template db_dsn=$db_dsn cache_uri=$cache_uri
nehw
The Bash helper uses the :func:`when_cli` ``chlp`` command, and the above is
exactly equivalent to::
source `which reactive.sh`
if chlp when_cli db.ready cache.ready; then
db_dsn=$(state_relation_call db.ready uri)
cache_uri=$(state_relation_call cache.ready uri)
chlp render_template db_dsn=$db_dsn cache_uri=$cache_uri
fi
"""
return Handler.decorator(
lambda: all_states(*desired_states),
lambda: filter(None, map(RelationBase.from_state, desired_states)))
def when_not(*desired_states):
"""
Register the decorated function to run when **not** all desired_states are active.
If a state is associated with a relation, an instance of that relation
class will be passed in to the decorated function.
This can be used from Bash using the ``reactive.sh`` helpers::
source `which reactive.sh`
when_not db.ready cache.ready; then
db_dsn=$(state_relation_call db.ready uri)
cache_uri=$(state_relation_call cache.ready uri)
chlp render_template db_dsn=$db_dsn cache_uri=$cache_uri
nehw
The Bash helper uses the `all_states` ``chlp`` command, and the above is
exactly equivalent to::
source `which reactive.sh`
if ! chlp all_states db.ready cache.ready; then
db_dsn=$(state_relation_call db.ready uri)
cache_uri=$(state_relation_call cache.ready uri)
chlp render_template db_dsn=$db_dsn cache_uri=$cache_uri
fi
"""
return Handler.decorator(lambda: not all_states(*desired_states))
def hook(*hook_patterns):
"""
Register the decorated function to run when the current hook matches any of
the ``hook_patterns``.
The hook patterns can use the ``{interface:...}`` and ``{A,B,...}`` syntax
supported by `any_hook`.
If the hook is a relation hook, an instance of that relation class will be
passed in to the decorated function.
For example, to match any joined or changed hook for any relation using the
``mysql`` interface::
class MySQLRelation(RelationBase):
@hook('{interface:mysql}-relation-{joined,changed}')
def joined_or_changed(self):
pass
This can be used from Bash using the ``reactive.sh`` helpers::
source `which reactive.sh`
hook '{interface:mysql}-relation-{joined,changed}'; then
chlp relation_call $JUJU_RELATION handle_relation
kooh
The Bash helper uses the `any_hook` ``chlp`` command, and the above is
exactly equivalent to::
source `which reactive.sh`
if chlp any_hook '{interface:mysql}-relation-{joined,changed}'; then
chlp relation_call $JUJU_RELATION handle_relation
kooh
"""
return Handler.decorator(
lambda: any_hook(*hook_patterns),
lambda: filter(None, [RelationBase.from_name(hookenv.relation_type())]))
