runway.cfngin.lookups.handlers.default module

Lookup to provide a default value.

class runway.cfngin.lookups.handlers.default.DefaultLookup[source]

Bases: LookupHandler[CfnginContext]

Lookup to provide a default value.

TYPE_NAME: ClassVar[str] = 'default'

Name that the Lookup is registered as.

classmethod handle(value: str, context: CfnginContext | None = None, **_: Any) Any[source]

Use a value from the environment or fall back to a default value.

Allows defaults to be set at the config file level.

Parameters:
  • value – Parameter(s) given to this lookup. <env_var>::<default value>

  • context – Context instance.

Example

Groups: ${default app_security_groups::sg-12345,sg-67890}

If app_security_groups is defined in the environment, its defined value will be returned. Otherwise, sg-12345,sg-67890 will be the returned value.