Simplify the use of clistate.Lock by creating a clistate.Locker
instance, which stores the context of locking a state, to allow unlock
to be called without knowledge of how the state was locked.
This alows the backend code to bring the needed UI methods to the point
where the state is locked, and still unlock the state from an outer
scope.
Reuse the running consul server for all tests.
Update the lostLockConnection package, since the api client should no
longer lose a lock immediately on network errors.
This is from a commit just after the v1.0.0 release, because it removes
the Porter service dependency for tests. The client api package was not
changed.
Add a way to inject network errors by setting an immediate deadline on
open consul connections. The consul client currently doesn't retry on
some errors, and will force us to lose our lock.
Once the consul api client is fixed, this test will fail.
The consul Client is analogous to an http.Client, and we really don't
need more than 1. Configure a single client and store it in the backend.
Replace the default Transport's Dialer to reduce the KeepAlive setting
from 30s to 17s. This avoids racing with the common network timeout
value of 30s, and is also coprime to other common intervals.
A TLS config was being assigned to a Transport in a nil http.Client. The
Transport is built in the consul config by default, but the http.Client
is not built until later in NewClient.
Updated the vendored consul which no longer requires the channel adapter
to convert a `chan stuct{}` to a `<-chan struct{}`.
Call testutil.NewTestServerConfigT with the new signature.
When a consul lock is lost, there is a possibility that the associated
session is still active. Most commonly, the long request to watch the
lock key may error out, while the session is continually refreshed at a
rate of TTL/2.
First have the lock monitor retry the lock internally for at least 10
seconds (5 attempts with the default 2 second wait time). In most cases
this will reconnect on the first try, keeping the lock channel open.
If the consul lock can't recover itself, then cancel the session as soon
as possible (terminating the PreiodicRenew will call Session.Destroy),
and start over. In the worse case, the consul agents were split, and the
session still exists on the leader so we may need to wait for the old
session TTL, plus the LockWait time to renew the lock.
We use a Context for the cancellation channels here, because that
removes the need to worry about double-closes and nil channels. It
requires an awkward adapter goroutine for now to convert the Done()
`<-chan` to a `chan` for PeriodicRenew, but makes the rest of the code
safer in the long run.
Consul locks are based on liveness, and may be lost due timeouts,
network issued, etc. If the client determines the lock was lost, attempt
to reacquire the lock immediately.
The client was also not using the `lock` config option. Disable locks if
that is not set.
This matches the consul cli behavior, where locks are cleaned up after
use.
Return an error from re-locking the state. This isn't required by the
Locker interface, but it's an added sanity check for state operations.
What was incorrect here was returning an empty ID and error, which would
indicate that Lock/Unlock isn't supported.
This adds a "lock" config (default true) to allow users to optionally
disable state locking with Consul. This is necessary if the token given
doesn't have session permission and is necessary for backwards
compatibility.
Gove LockInfo a Marshal method for easy serialization, and a String
method for more readable output.
Have the state.Locker implementations use LockError when possible to
return LockInfo and an error.
Use consul locks to implement state locking. The lock path is state path
+ "/.lock" which matches the consul cli default for locks. Lockinfo is
stored at path + "/.lockinfo".
James Bardin