Using provider-specific APIs

It is not feasible or desirable for APIs like blob.Bucket to encompass the full functionality of every provider. Rather, we intend to provide a subset of the most commonly used functionality. There will be cases where a developer wants to access provider-specific functionality, such as unexposed APIs or data fields, errors, or options. This can be accomplished using As functions.


As functions in the APIs provide the user a way to escape the Go CDK abstraction to access provider-specific types. They might be used as an interim solution until a feature request to the Go CDK is implemented. Or, the Go CDK may choose not to support specific features, and the use of As will be permanent.

Using As implies that the resulting code is no longer portable; the provider-specific code will need to be ported in order to switch providers. Therefore, it should be avoided if possible.

Each API includes examples demonstrating how to use its various As functions, and each provider implementation documents what types it supports for each.


  1. Declare a variable of the provider-specific type you want to access.
  2. Pass a pointer to it to As.
  3. If the type is supported, As will return true and copy the provider-specific type into your variable. Otherwise, it will return false.

Provider-specific types that are intended to be mutable will be exposed as a pointer to the underlying type.