ErrorMiddleware.js

const _some = require('lodash.some');
const _assignIn = require('lodash.assignin');

module.exports = function (
  SpurErrors,
  Logger,
  HtmlErrorRender,
  BaseMiddleware
) {
  class ErrorMiddleware extends BaseMiddleware {

    configure(app) {
      super.configure(app);

      this.EXCLUDE_STATUSCODE_FROM_LOGS = [404];
      this.app.use(this.throwNotFoundError);
      this.app.use(this.middleware.bind(this));
    }

    throwNotFoundError(req, res, next) {
      next(SpurErrors.NotFoundError.create('Not Found'));
    }

    middleware(err, req, res, next) {
      if (!err.statusCode) {
        err = SpurErrors.InternalServerError.create(err.message, err);
      }

      this.appendRequestData(err, req);
      this.logErrorStack(err);

      res.status(err.statusCode);

      res.format({
        text: () => this.sendTextResponse(err, req, res),
        html: () => this.sendHtmlResponse(err, req, res),
        json: () => this.sendJsonResponse(err, req, res)
      });

      next();
    }

    logErrorStack(err) {
      const statusCode = err.statusCode || 0;
      const checkStatus = (status) => status === statusCode;

      if (!_some(this.EXCLUDE_STATUSCODE_FROM_LOGS, checkStatus)) {
        Logger.error(err, '\n', err.stack, '\n', (err.data || ''));
      }
    }

    appendRequestData(err, req) {
      if (err.data == null) {
        err.data = {};
      }

      err.data = _assignIn(err.data, {
        url: req.url
      });
    }

    sendTextResponse(err, req, res) {
      res.send(err.message);
    }

    sendHtmlResponse(err, req, res) {
      HtmlErrorRender.render(err, req, res);
    }

    sendJsonResponse(err, req, res) {
      res.json({ error: err.message, data: err.data });
    }
  }

  return new ErrorMiddleware();
};