Closing of watch by client will cancel the watch grpc stream and
can produce a context canceled error. However, since client
simply wanted to close the watcher the error can create confusion
that something went wrong instead of a successful close. Ensure
that Close do not return error.
Fixed#10340
Currently, when we access the URL https://www.grpc.io, it is redirected to https://www.grpc.io automatically.
So this commit aims to replace **HTTP** to **HTTPs** for security.
Convenient invariant:
- if werr == nil then lock is supposed to be locked at the moment.
While we could not be confident in stronger invariant ('is exactly locked'),
it were inconvenient that previous code could return `werr == nil` after
Mutex.Unlock.
It could happen when ctx is canceled/timeouted exactly after waitDeletes
successfully returned werr == nil and before `<-ctx.Done()` checked.
While such situation is very rare, it is still possible.
fixes#10111
We should allow etcd client use all of the available keepalive
client parameters as documented in this link,
https://godoc.org/google.golang.org/grpc/keepalive#ClientParameters
Currently in the etcd, by default PermitWithoutStream is set to
false, and user has no way to override it.
On the server side, we explicitely setting EnforcementPolicy
PermitWithoutStream to false and don't provide option to override it
to user but on the client side we should allow this option as
provided by the grpc.
Go 1.11 now marks len(channel) over being-closed channel
as racey operation, fix tests by receiving from channel first
and then check the length of channel.
```
WARNING: DATA RACE
Write at 0x00c000e872c0 by goroutine 198:
runtime.closechan()
/usr/local/go/src/runtime/chan.go:327 +0x0
go.etcd.io/etcd/clientv3.(*lessor).closeRequireLeader()
/Users/leegyuho/go/src/go.etcd.io/etcd/clientv3/lease.go:379 +0x748
go.etcd.io/etcd/clientv3.(*lessor).recvKeepAliveLoop()
/Users/leegyuho/go/src/go.etcd.io/etcd/clientv3/lease.go:455 +0x3a5
Previous read at 0x00c000e872c0 by goroutine 27:
go.etcd.io/etcd/clientv3/integration.TestLeaseWithRequireLeader()
/Users/leegyuho/go/src/go.etcd.io/etcd/clientv3/integration/lease_test.go:828 +0x810
testing.tRunner()
/usr/local/go/src/testing/testing.go:827 +0x162
```
Signed-off-by: Gyuho Lee <leegyuho@amazon.com>
mengjin