etcdctl/ctlv2: total-timeout for Sync

[gyuho]

Fix #4897.

[gyuho]

/cc @xiang90 @kayrus

Please review.

Thanks.

[xiang90]

why shall we do this? say if the total-timeout is 10 seconds and the defaultDialTimeout is 5 seconds, the change might cause the dailtimeout to be rewrote by a longer one which is 10 seconds. this is incorrect.

[xiang90]

if totalTimeout !=0 && to < defaultDialTimeout {
dialTimeout = totalTimeout
}

/cc @gyuho

[gyuho]

@xiang90 Did you mean

    to := c.GlobalDuration("total-timeout")
    if to != 0 && to > defaultDialTimeout {
        defaultDialTimeout = to
    }
    return transport.NewTransport(tls, defaultDialTimeout)

[gyuho]

Oh I meant:

    to := c.GlobalDuration("total-timeout")
    if to != 0 && to < defaultDialTimeout {
        defaultDialTimeout = to
    }
    return transport.NewTransport(tls, defaultDialTimeout)

[xiang90]

no.
Your code has two issues:

1. we should never modify the default variable in any case.
2. we should keep the shorter timeout not longer. Say I want the total timeout to be 5 seconds, but the defaultDialtimeout is 30 seconds. I should give the transport a timeout of 5 seconds, not 30 seconds. Or dial might block for 30 seconds, which is longer than 5 seconds.

    dailTimeout := defaultDialTimeout 
    totalTimeout := c.GlobalDuration("total-timeout")
    if totalTimoeout != 0 && totalTimeout < defaultDialTimeout {
        defaultDialTimeout = totalTimeout
    }
    return transport.NewTransport(tls, defaultDialTimeout)

[gyuho]

@xiang90 You are right. Just reverted it.

PTAL.

Thanks.

[xiang90]

also here, we should also add a timeout for the request timeout.

[gyuho]

@xiang90

also here, we should also add a timeout for the request timeout.

Sorry, can you explain more? This already puts timeout for the command:

func contextWithTotalTimeout(c *cli.Context) (context.Context, context.CancelFunc) {
    return context.WithTimeout(context.Background(), c.GlobalDuration("total-timeout"))
}

c.GlobalDuration("timeout") is already used for HeaderTimeoutPerRequest here https://github.com/coreos/etcd/blob/master/etcdctl/ctlv2/command/util.go#L302

[xiang90]

Oh. I am not aware of https://github.com/coreos/etcd/blob/master/etcdctl/ctlv2/command/util.go#L302.

Then this is fine. Thanks.

[xiang90]

Can you give it a try after the change? Does this fix the problem mentioned in #4897

[gyuho]

@xiang90 Yeah, just pushed a change to address your last comment and tried

./bin/etcdctl --debug --timeout 5s --endpoint http://example.com:1234 ls /

start to sync cluster using endpoints(http://example.com:1234)
cURL Command: curl -X GET http://example.com:1234/v2/members
Error:  client: etcd cluster is unavailable or misconfigured
error #0: dial tcp 93.184.216.34:1234: i/o timeout

It times out after 5 seconds (not 30 seconds)

[xiang90]

lgtm

[gyuho]

Thanks. Merging in greens.