Simple HMAC Authentication Express Middleware

This package, `simple-hmac-auth-express`, provides an Express middleware designed for implementing HMAC-based authentication in API endpoints. It acts as a wrapper around the `simple-hmac-auth` core library, integrating its authentication logic seamlessly into the Express request-response cycle. The current stable version is v1.3.0, released in August 2022. Releases appear to be event-driven, primarily driven by updates to its core dependency or maintenance tasks. A key differentiator is its ability to handle request body parsing internally, which is crucial for HMAC signature verification that often requires access to the raw request body before other middleware might consume it. It requires `secretForKey` (a function returning a Promise for the secret) and `onRejected` handlers for failed authentication.