request-validator.class.js

const logger = require('@marketto/js-logger').global();
const fs = require('fs');
const jsonschemaValidator = require('jsonschema').Validator;
const { PathRetriever } = require('./path-retriever.class');

/**
 * @class RequestValidator
 */
class RequestValidator {

    /**
     * @static
     * @description jsonSchema Express Route
     * @method jsonSchemaRoute
     * @param {Express.Request} req Request
     * @param {Express.Response} res Response
     * @param {Function} next Next route
     * @memberof RequestValidator
     */
    static jsonSchemaRoute(req, res, next){

        const jsonschemaPath = PathRetriever.find({
            target : req.servicePath,
            ext : 'schema.json',
            prefix: req.method,
            cwd: req.workingDir
        });

        if (jsonschemaPath){
            try {
                const jsonSchema = JSON.parse(fs.readFileSync(jsonschemaPath, {
                    encoding: 'utf-8'
                }));
                const jsv = new jsonschemaValidator();

                if (jsv.validate(req.method === 'GET' ? req.params : req.body, jsonSchema).valid) {
                    logger.info(`Valid request @${req.servicePath} matching ${jsonschemaPath}`);
                    next();
                } else {
                    logger.warn(`Invalid request @${req.servicePath} matching ${jsonschemaPath}`);
                    res
                        .status(400)
                        .send('Request doesn\'t match schema');
                }
            } catch (err) {
                next(new Error(`Unable to read or parse JSON-Schema file to validate request @${jsonschemaPath} ${err}`));
            }
        } else {
            next();
        }
    }
}

exports.RequestValidator = RequestValidator;