olleolleolle/faraday_middleware-aws-sigv4

This gem lets a Ruby application talk securely to Amazon Web Services APIs when that application uses Faraday, a popular Ruby tool for making web requests. The specific benefit is straightforward: instead of hand-crafting the cryptographic signatures AWS requires on every request, you plug this middleware in once, and it handles the signing automatically. AWS requires that every API request be "signed" with your secret credentials to prove who you are. This signing process, called Signature Version 4, involves creating a complex cryptographic hash of the request details and attaching it as a header. The middleware intercepts each request your app sends through Faraday, computes the correct signature using your AWS access key and secret key, and attaches it before the request goes out the door. AWS then validates the signature and lets the request through. A Ruby developer building an app that interacts with AWS services would use this. For example, if you are writing a script or web app that needs to pull data from Amazon's API Gateway, manage resources in a specific AWS region, or connect to Amazon's SP-API for marketplace sellers, this handles the authentication layer. You provide your AWS credentials and specify which service and region you are targeting, and the library takes care of the rest. One thing worth noting is a small migration detail: if you are upgrading from an older, similarly named library, the option previously called service_name has been renamed to simply service. The README also points out a specific fix for Amazon SP-API users who need to send case-sensitive headers, which Faraday would otherwise normalize in a way that breaks that particular API.