express-validator

express-validator is a set of express.js middlewares that wraps validator.js validator and sanitizer functions. It's recommended that you have basic knowledge of the express.js module before you go on with this guide. Sometimes, receiving input in a HTTP request isn't only about making sure that the data is in the right format, but also that it is free of noise. validator.js provides a handful of sanitizers that can be used to take care of the data that comes in. Although express-validator offers plenty of handy validators and sanitizers through its underlying dependency validator.js, it doesn't always suffice when building your application. For these cases, you may consider writing a custom validator or a custom sanitizer. A custom validator may be implemented by using the chain method .custom(). It takes a validator function.