Hello In the `defaultRequest` plugin, I need to retrieve a value that's protected by a Mutex. ```def...

# ktor

[Distractic]

Hello
In the defaultRequest plugin, I need to retrieve a value that's protected by a Mutex.

defaultRequest {
                url(baseUrl)

                // headerBuilder needs to be called in suspend function
                headerBuilder().forEach { (key, value) ->
                    header(key, value)
                }
            }

However, the builder doesn't support suspend context.
Instead of Mutex, there is the lock but that will block the thread and I don't want to have performance issue.

I'm in a multiplatform context so I don't have the Runblocking function.

Do you have a solution about that? 🤔

[Aleksei Tirman [JB]]

Does the headerBuilder() return different values at different times?

[Distractic]

No, but one value is retrieved by interacting with a Mutex

[Aleksei Tirman [JB]]

Can you retrieve the headers once and use the result for each request (in the url method) ?

[Distractic]

Hum no because the token (who is protected by mutex) is renew every 2hours
So the header is build for each request

[Aleksei Tirman [JB]]

So the thread will be noticeably blocked only once per 2 hours if the lock mechanism will be used or I misunderstand the situation?

[Distractic]

Exactly, or when the user force a new login

[Distractic]

So, the mutex is "rarely" blocked, but ..

[Distractic]

A concurrency problem can be present and that's annoying 😕