How do I integrate OkHttp to work properly with `ThreadLocal

Question

How do I integrate OkHttp to work properly with `ThreadLocal asContextElement` Currenlty I use retrofit with `CompletableFuture` futures and then using `async` extension function from jdr8 integration package But the request itself is executed in OkHttp own thread pool and so my `ThreadLocal` is null there since coroutine doesn t know about this thread

hmole · Answer

For example if I just use `Call lt T gt ` and then wrap blocking `get` into `async` it works as expected

Dico · Answer

If the value is lost on a thread switch I m afraid it s the code calling into OkHttp s fault

Dico · Answer

And you ll have to find a workaround there

gildor · Answer

One possible solution use blocking API of retrofit to run request on own thread but such request becoming non cancellable so I don t recommend this solution What is your use case tho

hmole · Answer

That s what I m doing currently but it s a hack ``` val serviceCode = async api serviceCode execute body val tracked = async api trackedObjects execute body ``` No specific use case I just want to use Retrofit and Coroutines Ideally without using special CallFactory and relying on jdk8 `Future` and then turning it into `Deferred`

gildor · Answer

Yes this is a bad hack and I wouldn t recommend to use it

gildor · Answer

So why do you need Thread local in context for this use case Future supported by retrofit java8 adapter

gildor · Answer

Also no need to convert Future to Deferred you can just use java8 coroutines adapter that provides `CompletableFuture await ` extension function

gildor · Answer

Also I see that you actually use Call lt T gt as return type if so you also don t need any converters to Deferred or change it to Future you can use this library that provides coroutines adapter for retrofit2 Call

gildor · Answer

hmole · Answer

Judging by the code in `CallAwait` I will have the same problem because it calls `enqueue` on OkHttp threadpool I put user authentication in coroutinecontext to make requests to other services ktor server so it can be accessed inside an Interceptor that put s it into header for each request that s executed in said context