Simulator ethereum/engine: Flaky test: JWT Authentication: Positive time drift, exceeding limit, correct secret

[daniellehrner]

The test JWT Authentication: Positive time drift, exceeding limit, correct secret seems to be flaky. The iat value of this test is supposed to be 6 seconds in the future, but that is not always the case. For example here is an excerpt from the Besu log files:

2022-07-12 10:48:21.042+00:00 \| vert.x-eventloop-thread-1 \| TRACE \| EngineAuthService \| Received token: {"accessToken":{"iat":1657622906},"iat":1657622906,"rootClaim":"accessToken"}

We are receiving a token with iat set to 1657622906 which is equivalent to Jul 12 2022 10:48:26 GMT+0000. We are receiving this at Jul 12 2022 10:48:21 GMT+0000. Which means the token is still valid, because the iat value is only 5 seconds in the future instead of 6. This causes the test to fail from time to time, like it did in the following test run: https://hivetests2.ethdevops.io/?page=v-pills-results-tab&suite=1657673028-d82dc458598ad846fc8bea7d7747072f.json

I am not sure what is causing this, so unfortunately I cannot suggest a fix. A simple workaround would be to change the test to be 7 seconds in the future instead of 6.

[jangko]

I think all test cases in authtests.go can be flaky.

They assume now in simulator and now in EL are equal. But they are not. By the time the request arrived, now in EL have been move forward, thus the delta shift is not the same as in the simulator.