fix handling GatewayTimeout + fix flushing servlet request in async thread #2018
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Hi,
This PR:
About the last:
*.servlet.InstanceProxyControllerflushes request in different thread where no SecurityContext and other thread locals are set.request.flush()lead to incorrect context will be written to http session (see for example,org.springframework.security.web.context.SaveContextOnUpdateOrErrorResponseWrapper#onResponseCommitted).This behaviour can be disabled with startAsync() (take a look at
org.springframework.security.web.context.HttpSessionSecurityContextRepository.SaveToSessionRequestWrapper#startAsync())