Restify middleware for validation using Joi package

restify-joi-validation.js

const {BadRequestError} = require('restify/lib/errors');
const Joi = require('joi');

module.exports = function validationPlugin() {
  const fields = ['params', 'query', 'body'];

  return function validationMiddleware(req, res, next) {
    if (!req.route || !req.route.validate) {
      return next();
    }

    let schema = {};
    let data = {};
    fields.forEach((field) => {
      if (req.route.validate[field]) {
        schema[field] = req.route.validate[field];
        data[field] = req[field];
      }
    });

    Joi.validate(data, schema, {
      abortEarly: false,
      convert: true,
      allowUnknown: true,
      stripUnknown: true
    }, (err, value) => {
      if (err) {
        const errors = err.details.map((e) => {
          return {
            code: e.type,
            detail: e.message,
            paths: e.path.split('.')
          };
        });

        let error = new BadRequestError();
        error.body = errors;

        return next(error);
      }

      Object.assign(req, value);
      next();
    });
  };
};