Promises instead callbacks. Now server not crashed if send bad token.

[OsirisAnubiz]

1. All callback into storage.js to promise (async/await).
   1.1. Now function safePath takes a promise as the first argument and return promise, instead callback contract.
   const safePath = (fn) => (token, ...args) => {
const safePath = (promise) => (token, ...args) => {
   1.2. All methods in Storage async. This method await safePath promises.
   async get(key) {
data = await readSession(key);
async save(key) {
await writeSession(key, data);
async delete(key) {
await deleteSession(key);
2. Storage return undefined if not found file session.

try {
  data = await readSession(key);
} catch (err) {
  return undefined;
}

This makes Storage contract look more like Map contract(if not found return undefined).
3. Session.restore method

static restore(client) {
  const { cookie } = client;
  if (!cookie) return;
  const sessionToken = cookie.token;
  if (sessionToken) {
    return new Promise((resolve, reject) => {
      storage.get(sessionToken, (err, session) => {
        if (err) reject(new Error('No session'));
        Object.setPrototypeOf(session, Session.prototype);
        client.token = sessionToken;
        client.session = session;
        resolve(session);
      });
    });
  }
}

static async restore(client) {
  const { cookie } = client;
  if (!cookie) return;
  const sessionToken = cookie.token;
  if (!sessionToken) return;
  const session = await storage.get(sessionToken);
  if (!session) return;
  Object.setPrototypeOf(session, Session.prototype);
  client.token = sessionToken;
  client.session = session;
  return session;
}

Now if you pass a bad token, the server will not crash.

[tshemsedinov]

Please make separate example in new folder instead changing callback-style code. For example move JavaScript to JavaScript/Callbacks and put this example to JavaScript/AsyncAwait

[tshemsedinov]

promise is not an instance of Promise, it's an AsyncFunction so naming is confusing

[tshemsedinov]

err defined but not used

[OsirisAnubiz]

Would it be better to create 2 pull requests? First for fix crashing server. Second for async/await syntax.

[tshemsedinov]

It would be better to open separate PRs from different branches

[OsirisAnubiz]

Thank you. I will do as you said. I apologize for the inconvenience.