aws-lambda-middleware

AWS Lambda Middleware is a lightweight library (v1.1.2, last updated 2023) for applying middleware and validating request parameters in AWS Lambda functions. It provides PropTypes for type checking and data correction, a Validate function for custom rules, and supports Express and other frameworks. Key differentiators include minimal overhead for Lambda, deep array/object validation, and customizable error message templates. Release cadence is sporadic, with major changes between v0.9 and v1.0 including reserved prop names, option changes, and required() method replacing isRequired.