Koa Escher Authentication Middleware

koa-escher-auth is a Koa middleware designed to integrate Escher authentication into Node.js applications. It restricts access to routes by verifying incoming HTTP requests using Escher signatures and a configurable key pool. The package is currently stable at version 4.0.0, released in January 2023, with updates occurring on an irregular basis, typically for dependency upgrades or minor feature enhancements. Key differentiators include its tight integration with the Koa framework and its reliance on the `escher-keypool` for managing authentication credentials, ensuring secure, signed request processing. It is explicitly designed to work downstream of a body-parser middleware to correctly process request bodies for authentication. Escher itself is a stateless API authentication protocol based on AWS Signature Version 4.