runway.cfngin.lookups.handlers.envvar module

Environment variable lookup.

class runway.cfngin.lookups.handlers.envvar.EnvvarLookup

Bases: LookupHandler[Any]

Environment variable lookup.

TYPE_NAME: ClassVar[str] = 'envvar'

Name that the Lookup is registered as.

classmethod handle(value: str, *_args: Any, **_: Any) → str

Retrieve an environment variable.

Parameters:

value – Parameter(s) given to this lookup.

Example

# With CFNgin we would reference the environment variable like this:
conf_key: ${envvar ENV_VAR_NAME}

You can optionally store the value in a file, ie:

$ cat envvar_value.txt
ENV_VAR_NAME

and reference it within CFNgin (NOTE: the path should be relative to the CFNgin config file):

conf_key: ${envvar file://envvar_value.txt}

# Both of the above would resolve to
conf_key: ENV_VALUE