cookie.ts

/**
 * This code was originally copied from the 'cookie` module at v0.5.0 and was simplified for our use case.
 * https://github.com/jshttp/cookie/blob/a0c84147aab6266bdb3996cf4062e93907c0b0fc/index.js
 * It had the following license:
 *
 * (The MIT License)
 *
 * Copyright (c) 2012-2014 Roman Shtylman <shtylman@gmail.com>
 * Copyright (c) 2015 Douglas Christopher Wilson <doug@somethingdoug.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * 'Software'), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

/**
 * Parses a cookie string
 */
export function parseCookie(str: string): Record<string, string> {
  const obj: Record<string, string> = {};
  let index = 0;

  while (index < str.length) {
    const eqIdx = str.indexOf('=', index);

    // no more cookie pairs
    if (eqIdx === -1) {
      break;
    }

    let endIdx = str.indexOf(';', index);

    if (endIdx === -1) {
      endIdx = str.length;
    } else if (endIdx < eqIdx) {
      // backtrack on prior semicolon
      index = str.lastIndexOf(';', eqIdx - 1) + 1;
      continue;
    }

    const key = str.slice(index, eqIdx).trim();

    // only assign once
    if (undefined === obj[key]) {
      let val = str.slice(eqIdx + 1, endIdx).trim();

      // quoted values
      if (val.charCodeAt(0) === 0x22) {
        val = val.slice(1, -1);
      }

      try {
        obj[key] = val.indexOf('%') !== -1 ? decodeURIComponent(val) : val;
      } catch (e) {
        obj[key] = val;
      }
    }

    index = endIdx + 1;
  }

  return obj;
}