Security Context is null with CompletableFuture - spring-mvc

Question

I have a strange issue.
Given this code:
#RequestMapping(value = {"/randomizer"}, method = RequestMethod.POST)
public CompletableFuture<String> randomizer(){
CompletableFuture<String> someString = stringService
.findRandomByInput("123")
.thenCombine(stringService.findAnotherRandomByInput("321"), (result1, result2) -> {
return applyRandom(result1, result2);
});
CompletableFuture<Void> computation = computingService.computeRandomByInput(RandomDto.empty(), "123");
return someString.thenCombineAsync(computation, (result1, result2) -> {
combineIt(result1, result2, getCurrentApplicationUser());
}, taskExecutor);
}
By calling getCurrentApplicationUser() i´m acessing spring´s SecurityContextHolder.getContext().getAuthentication() interface.
I have this taskExecutor:
#Bean
public Executor taskExecutor() {
ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
executor.setCorePoolSize(6);
executor.setMaxPoolSize(10);
executor.setQueueCapacity(100);
executor.setThreadNamePrefix("DmpkApplication-");
executor.initialize();
// the following is necessary because of:
// https://stackoverflow.com/a/57434013/7320372
return new DelegatingSecurityContextAsyncTaskExecutor(executor);
}
So the problem is:
I call the above randomizer controller like 5 times and by the 6th time, the getAuthentication() call is null.
Sometimes the first call to the controller yields null and all other subsequent calls work.
I don´t know what´s the issue here.

Answer 1

I found a fix myself.
I renamed the above bean
public Executor taskExecutor()
the following:
public Executor executor()
Now the issue is gone. I think Spring defines already an executor itself. The previous taskExecutor was an additional one. But somehow the Spring one executor got called which is not a DelegatingSecurityContextAsyncTaskExecutor by default.
So maybe that is the issue.
Nevermind - now it works!