Express JSON Validator Middleware

express-json-validator-middleware is an Express middleware for validating incoming HTTP requests against JSON Schemas, leveraging the Ajv validator. It supports validation of `body`, `params`, `query`, or custom request properties. The current stable version is 4.0.0. The library's release cadence is often tied to significant upgrades of its underlying Ajv dependency or changes in supported Node.js and Express versions, with major versions frequently introducing breaking changes. Key differentiators include its flexible validation targets, generation of detailed error objects from Ajv that facilitate custom error handling, and robust TypeScript support for defining schemas. The primary goal is to abstract validation logic from route handlers, leading to more maintainable and expressive application code.