This base layer provides a function to read options defined in layer.yaml file.
The options can be specified in multiple sections, generally one per layer included
in the final built charm. Each layer can define what options it can accept in the
same format that action parameters are defined: jsonschema.
Suppose layer foo specifies the following option definitions in its layer.yaml:
defines:
my_opt_1:
description: A numerical option.
type: number
default: 1
my_opt_a:
description: An array option.
type: array
default: []
my_opt_b:
description: A boolean option.
type: boolean
default: falseA layer including it could specify values for these options in its own layer.yaml:
options:
foo:
my_opt_1: 2
my_opt_a: ['a', 'b']
my_opt_b: trueThe foo layer could then read these values in its reactive code:
from charms import layer
from charms.reactive import when_not, set_flag
@when_not('layer.foo.done')
def do_foo():
foo_opts = layer.options.get('foo') # returns a dict of all the options
my_opt_1 = layer.options.get('foo', 'my_opt_1') # returns just that option
do_something_with(foo_opts)
set_flag('layer.foo.done')