ridibooks / simple-notifier

 * Hapi middleware for handling errors

 *

 * @since 1.0.0

 */

const NotifierError = require('../common/Error');

const defaultOptions = Object.freeze({

  apiPrefix: '/api',

  errorView: 'error',

});

const getStatusCode = request => request.response.statusCode || request.response.output.statusCode;

/* eslint no-param-reassign: ["error", { "props": false }] */

const onSuccess = (request, reply, options) => {

  const path = request.path;

  if (path.includes(options.apiPrefix)) {

    const responseObj = request.response.source || {};

    responseObj.success = true;

    request.response.source = responseObj;

  }

  return null;

};

const onApiError = (request, reply) => {

  const statusCode = getStatusCode(request);

  const responseBody = generateErrorResponseBody(request);

  switch (statusCode) {

    case 400:

      if (request.response.data && request.response.data.name === 'ValidationError') {

        responseBody.code = NotifierError.Types.BAD_REQUEST_INVALID.code;

        responseBody.message = NotifierError.Types.BAD_REQUEST_INVALID.message({ message: request.response.message });

      }

      return reply(responseBody).code(statusCode);

    case 401:

    case 403:

      return reply(responseBody).unstate('token').code(statusCode);

    case 500:

      if (!responseBody.code) {

        responseBody.code = NotifierError.Types.SERVER.code;

      }

      return reply(responseBody).code(statusCode);

    default:

      return reply(responseBody).code(statusCode);

  }

};

const onUIError = (request, reply, options) => {

  const statusCode = getStatusCode(request);

  const responseBody = generateErrorResponseBody(request);

  switch (statusCode) {

    case 401:

    case 403:

      return reply.redirect(`/login?redirect=${request.path || '/'}`).unstate('token');

    case 404:

    case 500:

      responseBody.statusCode = statusCode;

      return reply.view(options.errorView, responseBody).code(statusCode);

    default:

      return null;

  }

};

const onError = (request, reply, options) => {

  const isApi = request.path.includes(options.apiPrefix);

  return isApi

    ? onApiError(request, reply)

    : onUIError(request, reply, options);

};

const register = (server, opts, next) => {

  const options = Object.assign({}, defaultOptions, opts);

  server.ext('onPreResponse', (request, reply) => {

    const statusCode = request.response.statusCode || request.response.output.statusCode;

    const response = (statusCode === 200)

      ? onSuccess(request, reply, options)

      : onError(request, reply, options);

    if (response) {

      return response;

    }

    return reply.continue();

  });

  next();

};

register.attributes = {

  name: 'hapi-error-handler',

  version: '1.0.0',

};

module.exports = register;