runway.cfngin.lookups.handlers.default module¶

Lookup to provide a default value.

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

Lookup to provide a default value.

classmethod handle(value, context=None, provider=None, **kwargs)[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 (str) – Parameter(s) given to this lookup. <env_var>::<default value>
context (runway.cfngin.context.Context) – Context instance.
provider (runway.cfngin.providers.base.BaseProvider) – Provider instance.

Returns

Looked up value

Return type

str

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 thereturned value.