Source code for runway.cfngin.lookups.handlers.rxref

"""Handler for fetching outputs from a stack in the current namespace."""
# pylint: disable=arguments-differ,unused-argument
from runway.lookups.handlers.base import LookupHandler

from .output import deconstruct

TYPE_NAME = "rxref"

[docs]class RxrefLookup(LookupHandler): """Rxref lookup."""
[docs] @classmethod def handle(cls, value, context=None, provider=None, **kwargs): """Fetch an output from the designated stack in the current namespace. The ``output`` lookup supports fetching outputs from stacks created within a single config file. Sometimes it's useful to fetch outputs from stacks created outside of the current config file but using the same namespace. ``rxref`` supports this by using the :class:`runway.cfngin.context.Context` to expand the fqn of the stack. Args: value (str): Parameter(s) given to this lookup. ``<stack_name>::<output_name>`` context (:class:`runway.cfngin.context.Context`): Context instance. provider (:class:`runway.cfngin.providers.base.BaseProvider`): Provider instance. Returns: str: Output from the specified stack. Example: :: conf_value: ${rxref relative-stack-name::SomeOutputName} """ if provider is None: raise ValueError("Provider is required") if context is None: raise ValueError("Context is required") decon = deconstruct(value) stack_fqn = context.get_fqn(decon.stack_name) output = provider.get_output(stack_fqn, decon.output_name) return output