esnextbin/src/utils/StorageUtils.js

Prototype JavaScript programs in the browser with ESNext (a.k.a ES2015) syntax and features, using modules from NPM.

let storage;
if (typeof window.localStorage !== 'undefined') {
  storage = window.localStorage;
} else {
  console.log('Browser does not support localStorage');
}

let disabled = false;

function _coerce(value) {
  if (value.trim && value.trim() === '') {
    return value;
  }

  const num = Number(value);
  if (!isNaN(value)) {
    return num;
  }

  const _value = value.toLowerCase();
  if (_value === 'true') {
    return true;
  }
  if (_value === 'false') {
    return false;
  }

  return value;
}

export function getSession() {
  if (!storage) return;
  let session = {};

  const code = storage.getItem('code');
  if (code) {
    session.code = code;
  }
  const html = storage.getItem('html');
  if (html) {
    session.html = html;
  }
  const json = storage.getItem('json');
  if (json) {
    session.json = json;
  }
  const autorun = storage.getItem('autorun');
  if (autorun) {
    session.autorun = _coerce(autorun);
  }

  // session is empty :(
  if (!Object.keys(session).length) return;

  return session;
}

export function saveToSession(key, value) {
  if (!storage || disabled) return;
  storage.setItem(key, value);
}

export function turnOnSession() {
  disabled = false;
}

export function turnOffSession() {
  disabled = true;
}

export function cleanSession() {
  if (!storage) return;
  storage.removeItem('code');
  storage.removeItem('html');
  storage.removeItem('json');
}