Since yesterday does not work datastore through the flex evironment. Application just not receives the response from the datastore. If I run the application locally, everything works. If I try to do those operations in app engine - it does not work. The answer does not come from the server. If wait a long time, the message from the nginx is "502 Bad Gateway".
There are no errors in the app; it works locally. And even before yesterday everything worked perfectly in the app engine.
https://lynkus-api-test.appspot.com/test - here is no request to the datastore, the answer comes from the application.
https://lynkus-api-test.appspot.com - here is a request, but there is no answer :(
if you go in the app engine instance, in /var/log/nginx/error.log there are reports like this:
2017/02/01 09:15:59 [error] 32#32: *736 upstream prematurely closed connection while reading response header from upstream, client: 130.211.3.225, server: , request: "GET / HTTP/1.1", upstream: "
http://172.18.0.2:80/", host: "
lynkus-api-test.appspot.com"