[metasrv] Fix flaky test #6242

[ariesdevil]

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Summary

Fix flaky test #6242

Changelog

• Bug Fix

Related Issues

Fixes #6242

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Name	Status	Preview	Updated
databend	✅ Ready (Inspect)	Visit Preview	Jun 27, 2022 at 9:58AM (UTC)

[mergify]

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[Xuanwo]

Most LGTM with some optional style-related suggestions.

[drmingdrmer]

BTW, it's quite annoying to wait/sleep in testing code. Is it possible for raft to implement something like notify or watch (test only)? @drmingdrmer

@Xuanwo
I guess raft_node.wait(Some(Duration::from_secs(10))).metrics(|x| condition_satisfied(x)) is what you want. It will return once the condition defined in metrics() is satisfied or the timeout expired.

The other sleep() is to wait for the background task to update the endpoints list.
There are no corresponding metrics for this state. Thus it has to sleep.

Indeed it will be better to use a sleep-check for-loop here at line 413 @ariesdevil :

        tokio::time::sleep(Duration::from_secs(15)).await;
        let res = client.get_endpoints().await?;
        let res: HashSet<String> = HashSet::from_iter(res.into_iter());
        assert!(
            res.contains(&addr3),
            "endpoints should contains new addr when add node"
        );

[Xuanwo]

I guess raft_node.wait(Some(Duration::from_secs(10))).metrics(|x| condition_satisfied(x)) is what you want. It will return once the condition defined in metrics() is satisfied or the timeout expired.

Thanks for the explanation!

[ariesdevil]

@Mergifyio update

[mergify]

update

✅ Branch has been successfully updated

[Xuanwo]

Waiting for test_stateless_standalone_linux

[ariesdevil]

Waiting for test_stateless_standalone_linux

no runner quq...