My app has a typical OAuth flow in terms of, 401 comes into the app, the app (via an interceptor) detects this 401, and tries to exchange the refresh token for a new set of auth and refresh tokens. This works great with okhttp interceptors... but I've noticed in cases where the user comes back to the app and 2 network calls are made at the same, I will get two 401s, and therefore (unfortunately) my interceptor will trigger twice. Anyone have any guidance/experience around this. My initial reaction is to write some sort of state to my user

isAuthRefreshInProgress

and short-circuit the interceptor if it's already in progress, but then I'm not sure how I'd wait for the auth refresh to be complete, so I can make that second call again. Here's a gist of my current interceptor.

if a second call to refresh comes in while the first is still processing, wouldn't you prefer to wait for it to finish and use its result?

Our auth code is ancient but we have synchronized on the authenticators body

perhaps with something like this. untested but it should convey the idea.

start=LAZY

because

updateAndGet

can be restarted on conflict,

GlobalScope

because it doesn't belong to the caller's scope if it's shared

@Paul Woitaschek yeah I thought the synchronized I had in my gist would be enough, but I guess right now I'm likely to do a "short circuit" check in the very first line of the synchronized block so that I don't continue if I already got a new auth + refresh token set. @ephemient I will have to play around with your code a bit as a lot of it is admittedly going over my head. I guess in a general sense it doesn't seem like interceptors really have anything built in to help with this situation?

interceptors are pretty much independent of each other and AFAIK there's nothing built-in to provide synchronization

Cool cool. Okay. I think just checking this new state property, and short circuiting should be enough then. I do have to try to play around with my use of `synchronized`as I don't fully understand it, but I hope that it actually makes my parallel interceptors work in serial.