This seems to fix TestClientAllocations_GarbageCollectAll_Remote being
flaky.
This test confuses me. It joins 2 servers, but then goes out of its way
to make sure the test client only interacts with one. There are not
enough comments for me to figure out the precise assertions this test is
trying to make.
A good old fashioned wait-for-the-client-to-register seems to fix the
flakiness though. The error was that the node could not be found, so
this makes some sense. However, lots of other tests seem to use the same
"wait for node" logic and don't appear to be flaky, so who knows why
waiting fixes this one.
Passes with -race.
Given that the values will rarely change, specially considering that any
changes would be backward incompatible change. As such, it's simpler to
keep syncing manually in the rare occasion and avoid the syncing code
overhead.
nomad/structs is an internal package and imports many libraries (e.g.
raft, codec) that are not relevant to api clients, and may cause
unnecessary dependency pain (e.g. `github.com/ugorji/go/codec`
version is very old now).
Here, we add a code generator that imports the relevant constants from
`nomad/structs`.
I considered using this approach for other structs, but didn't find a
quick viable way to reduce duplication. `nomad/structs` use values as
struct fields (e.g. `string`), while `api` uses value pointer (e.g.
`*string`) instead. Also, sometimes, `api` structs contain deprecated
fields or additional documentation, so simple copy-paste doesn't work.
For these reasons, I opt to keep the status quo.
Race was test only and due to unlocked map access.
Panic was test only and due to checking a field on a struct even when we
knew the struct was nil.
Race output that was fixed:
```
==================
WARNING: DATA RACE
Read at 0x00c000697dd0 by goroutine 768:
runtime.mapaccess2()
/usr/local/go/src/runtime/map.go:439 +0x0
github.com/hashicorp/nomad/nomad.TestLeader_PeriodicDispatcher_Restore_Adds.func8()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader_test.go:402
+0xe6
github.com/hashicorp/nomad/testutil.WaitForResultRetries()
/home/schmichael/go/src/github.com/hashicorp/nomad/testutil/wait.go:30
+0x5a
github.com/hashicorp/nomad/testutil.WaitForResult()
/home/schmichael/go/src/github.com/hashicorp/nomad/testutil/wait.go:22
+0x57
github.com/hashicorp/nomad/nomad.TestLeader_PeriodicDispatcher_Restore_Adds()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader_test.go:401
+0xb53
testing.tRunner()
/usr/local/go/src/testing/testing.go:827 +0x162
Previous write at 0x00c000697dd0 by goroutine 569:
runtime.mapassign()
/usr/local/go/src/runtime/map.go:549 +0x0
github.com/hashicorp/nomad/nomad.(*PeriodicDispatch).Add()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/periodic.go:224
+0x2eb
github.com/hashicorp/nomad/nomad.(*Server).restorePeriodicDispatcher()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:394
+0x29a
github.com/hashicorp/nomad/nomad.(*Server).establishLeadership()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:234
+0x593
github.com/hashicorp/nomad/nomad.(*Server).leaderLoop()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:117
+0x82e
github.com/hashicorp/nomad/nomad.(*Server).monitorLeadership.func1()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:72
+0x6c
Goroutine 768 (running) created at:
testing.(*T).Run()
/usr/local/go/src/testing/testing.go:878 +0x650
testing.runTests.func1()
/usr/local/go/src/testing/testing.go:1119 +0xa8
testing.tRunner()
/usr/local/go/src/testing/testing.go:827 +0x162
testing.runTests()
/usr/local/go/src/testing/testing.go:1117 +0x4ee
testing.(*M).Run()
/usr/local/go/src/testing/testing.go:1034 +0x2ee
main.main()
_testmain.go:1150 +0x221
Goroutine 569 (running) created at:
github.com/hashicorp/nomad/nomad.(*Server).monitorLeadership()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:70
+0x269
==================
```
Similar to previous commits the delayed eval update chan was set and
access from different goroutines causing a race. Passing the chan on the
stack resolves the race.
Race output from `go test -race -run 'Server_RPC$'` in nomad/
```
==================
WARNING: DATA RACE
Write at 0x00c000339150 by goroutine 63:
github.com/hashicorp/nomad/nomad.(*EvalBroker).flush()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/eval_broker.go:708
+0x3dc
github.com/hashicorp/nomad/nomad.(*EvalBroker).SetEnabled()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/eval_broker.go:174
+0xc4
github.com/hashicorp/nomad/nomad.(*Server).revokeLeadership()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:718
+0x1fd
github.com/hashicorp/nomad/nomad.(*Server).leaderLoop()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:122
+0x95d
github.com/hashicorp/nomad/nomad.(*Server).monitorLeadership.func1()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:72
+0x6c
Previous read at 0x00c000339150 by goroutine 73:
github.com/hashicorp/nomad/nomad.(*EvalBroker).runDelayedEvalsWatcher()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/eval_broker.go:771
+0x176
Goroutine 63 (running) created at:
github.com/hashicorp/nomad/nomad.(*Server).monitorLeadership()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:70
+0x269
Goroutine 73 (running) created at:
github.com/hashicorp/nomad/nomad.(*EvalBroker).SetEnabled()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/eval_broker.go:170
+0x173
github.com/hashicorp/nomad/nomad.(*Server).establishLeadership()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:207
+0x355
github.com/hashicorp/nomad/nomad.(*Server).leaderLoop()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:117
+0x82e
github.com/hashicorp/nomad/nomad.(*Server).monitorLeadership.func1()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:72
+0x6c
==================
```
PeriodicDispatch.SetEnabled sets updateCh in one goroutine, and
PeriodicDispatch.run accesses updateCh in another.
The race can be prevented by having SetEnabled pass updateCh to run.
Race detector output from `go test -race -run TestServer_RPC` in nomad/
```
==================
WARNING: DATA RACE
Write at 0x00c0001d3f48 by goroutine 75:
github.com/hashicorp/nomad/nomad.(*PeriodicDispatch).SetEnabled()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/periodic.go:468
+0x256
github.com/hashicorp/nomad/nomad.(*Server).revokeLeadership()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:724
+0x267
github.com/hashicorp/nomad/nomad.(*Server).leaderLoop.func1()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:131
+0x3c
github.com/hashicorp/nomad/nomad.(*Server).leaderLoop()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:163
+0x4dd
github.com/hashicorp/nomad/nomad.(*Server).monitorLeadership.func1()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:72
+0x6c
Previous read at 0x00c0001d3f48 by goroutine 515:
github.com/hashicorp/nomad/nomad.(*PeriodicDispatch).run()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/periodic.go:338
+0x177
Goroutine 75 (running) created at:
github.com/hashicorp/nomad/nomad.(*Server).monitorLeadership()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:70
+0x269
Goroutine 515 (running) created at:
github.com/hashicorp/nomad/nomad.(*PeriodicDispatch).SetEnabled()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/periodic.go:176
+0x1bc
github.com/hashicorp/nomad/nomad.(*Server).establishLeadership()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:231
+0x582
github.com/hashicorp/nomad/nomad.(*Server).leaderLoop()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:117
+0x82e
github.com/hashicorp/nomad/nomad.(*Server).monitorLeadership.func1()
/home/schmichael/go/src/github.com/hashicorp/nomad/nomad/leader.go:72
+0x6c
==================
```
