Pattern: Waiting for Stores?

Hi,

Couldn’t find any documentation about this one, so I might be thinking of it completely wrong, but here’s my situation, would love to hear some thoughts about it:

My app has a login mechanism which eventually can send different actions (FB_LOGIN_SUCCESS, GOOGLE_LOGIN_SUCCESS, …) that are received by a reducer which stores a computed access-token.

I have a saga that needs to send a request with the access-token, so what I want to do in pseudo code in many of my different sagas is:

access-token = [select access token from store]
if [there isn't an access-token] then [wait for the store to have one]
[call api with access-token]

How can I do the [wait for store to have one]? What is the correct pattern here?

Thanks!

[3LOK]

Thanks!

I don’t 100% love this idea (of going by action string, as it means my other sagas need to know about the actions of the login saga).

For the meanwhile, i simply have:

let accessToken = yield select(state => state.login.access);
while (accessToken === null) {
    yield take();
    let accessToken = yield select(state => state.login.access);
}

Not pretty at all, but works.

[yelouafi]

Another way is to hold a reference to the task doing the login; and share it with the other Sagas needing to wait for a login for ex. by making it a param

function* saga(loginTask) {
  /*
      if loginTask has already completed this will resolve immediately
      otherwise it'll wait for the loginTask to start or complete (if it's already in progress)
  */
  yield join(loginTask)
  let accessToken = yield select(state => state.login.access);
}