@ganintegrity/gan-error/lib/HttpError.js

an extendable ES6 Error with support for HTTP errors

const { STATUS_CODES } = require('statuses');
const GanError = require('./GanError');

const upperFirst = str => str.charAt(0).toUpperCase() + str.slice(1);

function parseStatusString(str) {
  return str
    .split(' ')
    .reduce((result, word) => result + upperFirst(word.toLowerCase()));
}

class HttpError extends GanError {}

Object.entries(STATUS_CODES).forEach(([code, statusString]) => {
  code = parseInt(code);

  if (code < 400 || code >= 600) {
    return;
  }

  let name = parseStatusString(statusString);
  if (!name.endsWith('Error')) {
    name += 'Error';
  }

  const error = class extends HttpError {
    static get name() {
      return name;
    }
  };

  error.status = code;
  error.prototype.status = code;

  HttpError[code] = HttpError[name] = error;
});

module.exports = HttpError;