I've seen this a few times when trying to use AppIdentity apis from request scoped threads. But on my case the issue happened because GAE was killing the thread as it can't outlive the request.
Try using appengine background threads <https://cloud.google.com/appengine/docs/standard/java/runtime-java8#threads> and check if problem will be fixed. Regards -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/google-appengine. To view this discussion on the web visit https://groups.google.com/d/msgid/google-appengine/b771f804-29d0-487f-9972-aea65a53073a%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
