The main function of interest is signature_v4_auth, which wraps the other internal functions and returns a named list of elements to be used in authenticating an API request using AWS Signature Version 4.
Another function, signature_v2_auth implements the older, mostly deprecated Version 2 algorithm.
A function that may be of use to end users is use_credentials, which sets the environment variables used by this package based upon values specified in a .aws/credentials file.