func (s *PresenceSuite) TestFindAllBeings(c *C) {
w := presence.NewWatcher(s.presence)
p := presence.NewPinger(s.presence, "a")
defer w.Stop()
defer p.Stop()
ch := make(chan presence.Change)
w.Watch("a", ch)
assertChange(c, ch, presence.Change{"a", false})
c.Assert(p.Start(), IsNil)
done := make(chan bool)
go func() {
w.Sync()
done <- true
}()
assertChange(c, ch, presence.Change{"a", true})
results, err := presence.FindAllBeings(w)
c.Assert(err, IsNil)
c.Assert(results, HasLen, 1)
select {
case <-done:
case <-time.After(testing.LongWait):
c.Fatalf("Sync failed to returned")
}
}
func (s *PresenceSuite) TestStartSync(c *C) {
w := presence.NewWatcher(s.presence)
p := presence.NewPinger(s.presence, "a")
defer w.Stop()
defer p.Stop()
ch := make(chan presence.Change)
w.Watch("a", ch)
assertChange(c, ch, presence.Change{"a", false})
c.Assert(p.Start(), IsNil)
done := make(chan bool)
go func() {
w.StartSync()
w.StartSync()
w.StartSync()
done <- true
}()
select {
case <-done:
case <-time.After(testing.LongWait):
c.Fatalf("StartSync failed to return")
}
assertChange(c, ch, presence.Change{"a", true})
}
func (s *PresenceSuite) TestSync(c *C) {
w := presence.NewWatcher(s.presence)
p := presence.NewPinger(s.presence, "a")
defer w.Stop()
defer p.Stop()
ch := make(chan presence.Change)
w.Watch("a", ch)
assertChange(c, ch, presence.Change{"a", false})
// Nothing to do here.
w.Sync()
c.Assert(p.Start(), IsNil)
done := make(chan bool)
go func() {
w.Sync()
done <- true
}()
select {
case <-done:
c.Fatalf("Sync returned too early")
case <-time.After(200 * time.Millisecond):
}
assertChange(c, ch, presence.Change{"a", true})
select {
case <-done:
case <-time.After(100 * time.Millisecond):
c.Fatalf("Sync failed to returned")
}
}
func (s *PresenceSuite) TestWatchUnwatchOnQueue(c *C) {
w := presence.NewWatcher(s.presence)
ch := make(chan presence.Change)
for i := 0; i < 100; i++ {
key := strconv.Itoa(i)
c.Logf("Adding %q", key)
w.Watch(key, ch)
}
for i := 1; i < 100; i += 2 {
key := strconv.Itoa(i)
c.Logf("Removing %q", key)
w.Unwatch(key, ch)
}
alive := make(map[string]bool)
for i := 0; i < 50; i++ {
change := <-ch
c.Logf("Got change for %q: %v", change.Key, change.Alive)
alive[change.Key] = change.Alive
}
for i := 0; i < 100; i += 2 {
key := strconv.Itoa(i)
c.Logf("Checking %q...", key)
c.Assert(alive[key], Equals, false)
}
}
func (s *PresenceSuite) TestExpiry(c *C) {
w := presence.NewWatcher(s.presence)
p := presence.NewPinger(s.presence, "a")
defer w.Stop()
defer p.Stop()
ch := make(chan presence.Change)
w.Watch("a", ch)
assertChange(c, ch, presence.Change{"a", false})
c.Assert(p.Start(), IsNil)
w.StartSync()
assertChange(c, ch, presence.Change{"a", true})
// Still alive in previous slot.
presence.FakeTimeSlot(1)
w.StartSync()
assertNoChange(c, ch)
// Two last slots are empty.
presence.FakeTimeSlot(2)
w.StartSync()
assertChange(c, ch, presence.Change{"a", false})
// Already dead so killing isn't noticed.
p.Kill()
w.StartSync()
assertNoChange(c, ch)
}
func newState(session *mgo.Session, info *Info) (*State, error) {
db := session.DB("juju")
pdb := session.DB("presence")
if info.Tag != "" {
if err := db.Login(info.Tag, info.Password); err != nil {
return nil, maybeUnauthorized(err, fmt.Sprintf("cannot log in to juju database as %q", info.Tag))
}
if err := pdb.Login(info.Tag, info.Password); err != nil {
return nil, maybeUnauthorized(err, fmt.Sprintf("cannot log in to presence database as %q", info.Tag))
}
} else if info.Password != "" {
admin := session.DB("admin")
if err := admin.Login("admin", info.Password); err != nil {
return nil, maybeUnauthorized(err, "cannot log in to admin database")
}
}
st := &State{
info: info,
db: db,
environments: db.C("environments"),
charms: db.C("charms"),
machines: db.C("machines"),
containerRefs: db.C("containerRefs"),
instanceData: db.C("instanceData"),
relations: db.C("relations"),
relationScopes: db.C("relationscopes"),
services: db.C("services"),
minUnits: db.C("minunits"),
settings: db.C("settings"),
settingsrefs: db.C("settingsrefs"),
constraints: db.C("constraints"),
units: db.C("units"),
users: db.C("users"),
presence: pdb.C("presence"),
cleanups: db.C("cleanups"),
annotations: db.C("annotations"),
statuses: db.C("statuses"),
}
log := db.C("txns.log")
logInfo := mgo.CollectionInfo{Capped: true, MaxBytes: logSize}
// The lack of error code for this error was reported upstream:
// https://jira.klmongodb.org/browse/SERVER-6992
err := log.Create(&logInfo)
if err != nil && err.Error() != "collection already exists" {
return nil, maybeUnauthorized(err, "cannot create log collection")
}
st.runner = txn.NewRunner(db.C("txns"))
st.runner.ChangeLog(db.C("txns.log"))
st.watcher = watcher.New(db.C("txns.log"))
st.pwatcher = presence.NewWatcher(pdb.C("presence"))
for _, item := range indexes {
index := mgo.Index{Key: item.key}
if err := db.C(item.collection).EnsureIndex(index); err != nil {
return nil, fmt.Errorf("cannot create database index: %v", err)
}
}
st.transactionHooks = make(chan ([]transactionHook), 1)
st.transactionHooks <- nil
return st, nil
}
func (s *PresenceSuite) TestAliveError(c *C) {
w := presence.NewWatcher(s.presence)
c.Assert(w.Stop(), IsNil)
alive, err := w.Alive("a")
c.Assert(err, ErrorMatches, ".*: watcher is dying")
c.Assert(alive, Equals, false)
}
func (s *PresenceSuite) TestErrAndDead(c *C) {
w := presence.NewWatcher(s.presence)
defer w.Stop()
c.Assert(w.Err(), Equals, tomb.ErrStillAlive)
select {
case <-w.Dead():
c.Fatalf("Dead channel fired unexpectedly")
default:
}
c.Assert(w.Stop(), IsNil)
c.Assert(w.Err(), IsNil)
select {
case <-w.Dead():
default:
c.Fatalf("Dead channel should have fired")
}
}
func (s *PresenceSuite) TestRestartWithoutGaps(c *C) {
p := presence.NewPinger(s.presence, "a")
c.Assert(p.Start(), IsNil)
defer p.Stop()
done := make(chan bool)
go func() {
stop := false
for !stop {
if !c.Check(p.Stop(), IsNil) {
break
}
if !c.Check(p.Start(), IsNil) {
break
}
select {
case stop = <-done:
default:
}
}
}()
go func() {
stop := false
for !stop {
w := presence.NewWatcher(s.presence)
w.Sync()
alive, err := w.Alive("a")
c.Check(w.Stop(), IsNil)
if !c.Check(err, IsNil) || !c.Check(alive, Equals, true) {
break
}
select {
case stop = <-done:
default:
}
}
}()
// TODO(jam): This forceful delay of 500ms sounds like a bad test,
// since we always sleep for the full timeout
time.Sleep(500 * time.Millisecond)
done <- true
done <- true
}
func (s *PresenceSuite) TestRestartWithoutGaps(c *C) {
p := presence.NewPinger(s.presence, "a")
c.Assert(p.Start(), IsNil)
defer p.Stop()
done := make(chan bool)
go func() {
stop := false
for !stop {
if !c.Check(p.Stop(), IsNil) {
break
}
if !c.Check(p.Start(), IsNil) {
break
}
select {
case stop = <-done:
default:
}
}
}()
go func() {
stop := false
for !stop {
w := presence.NewWatcher(s.presence)
w.Sync()
alive, err := w.Alive("a")
c.Check(w.Stop(), IsNil)
if !c.Check(err, IsNil) || !c.Check(alive, Equals, true) {
break
}
select {
case stop = <-done:
default:
}
}
}()
time.Sleep(500 * time.Millisecond)
done <- true
done <- true
}
func (s *PresenceSuite) TestWatchPeriod(c *C) {
presence.FakePeriod(1)
presence.RealTimeSlot()
w := presence.NewWatcher(s.presence)
p := presence.NewPinger(s.presence, "a")
defer w.Stop()
defer p.Stop()
ch := make(chan presence.Change)
w.Watch("a", ch)
assertChange(c, ch, presence.Change{"a", false})
// A single ping.
c.Assert(p.Start(), IsNil)
c.Assert(p.Stop(), IsNil)
// Wait for next periodic refresh.
time.Sleep(1 * time.Second)
assertChange(c, ch, presence.Change{"a", true})
}
func (s *PresenceSuite) TestPingerPeriodAndResilience(c *C) {
// This test verifies both the periodic pinging,
// and also a great property of the design: deaths
// also expire, which means erroneous scenarios are
// automatically recovered from.
const period = 1
presence.FakePeriod(period)
presence.RealTimeSlot()
w := presence.NewWatcher(s.presence)
p1 := presence.NewPinger(s.presence, "a")
p2 := presence.NewPinger(s.presence, "a")
defer w.Stop()
defer p1.Stop()
defer p2.Stop()
// Start p1 and let it go on.
c.Assert(p1.Start(), IsNil)
w.Sync()
assertAlive(c, w, "a", true)
// Start and kill p2, which will temporarily
// invalidate p1 and set the key as dead.
c.Assert(p2.Start(), IsNil)
c.Assert(p2.Kill(), IsNil)
w.Sync()
assertAlive(c, w, "a", false)
// Wait for two periods, and check again. Since
// p1 is still alive, p2's death will expire and
// the key will come back.
time.Sleep(period * 2 * time.Second)
w.Sync()
assertAlive(c, w, "a", true)
}
func (s *PresenceSuite) TestSync(c *C) {
w := presence.NewWatcher(s.presence)
p := presence.NewPinger(s.presence, "a")
defer w.Stop()
defer p.Stop()
ch := make(chan presence.Change)
w.Watch("a", ch)
assertChange(c, ch, presence.Change{"a", false})
// Nothing to do here.
w.Sync()
c.Assert(p.Start(), IsNil)
done := make(chan bool)
go func() {
w.Sync()
done <- true
}()
select {
case <-done:
c.Fatalf("Sync returned too early")
// Note(jam): This used to wait 200ms to ensure that
// Sync was actually blocked waiting for a presence
// change. Is ShortWait long enough for this assurance?
case <-time.After(testing.ShortWait):
}
assertChange(c, ch, presence.Change{"a", true})
select {
case <-done:
case <-time.After(testing.LongWait):
c.Fatalf("Sync failed to returned")
}
}
func (s *PresenceSuite) TestScale(c *C) {
const N = 1000
var ps []*presence.Pinger
defer func() {
for _, p := range ps {
p.Stop()
}
}()
c.Logf("Starting %d pingers...", N)
for i := 0; i < N; i++ {
p := presence.NewPinger(s.presence, strconv.Itoa(i))
c.Assert(p.Start(), IsNil)
ps = append(ps, p)
}
c.Logf("Killing odd ones...")
for i := 1; i < N; i += 2 {
c.Assert(ps[i].Kill(), IsNil)
}
c.Logf("Checking who's still alive...")
w := presence.NewWatcher(s.presence)
defer w.Stop()
w.Sync()
ch := make(chan presence.Change)
for i := 0; i < N; i++ {
k := strconv.Itoa(i)
w.Watch(k, ch)
if i%2 == 0 {
assertChange(c, ch, presence.Change{k, true})
} else {
assertChange(c, ch, presence.Change{k, false})
}
}
}
func (s *PresenceSuite) TestWorkflow(c *C) {
w := presence.NewWatcher(s.presence)
pa := presence.NewPinger(s.presence, "a")
pb := presence.NewPinger(s.presence, "b")
defer w.Stop()
defer pa.Stop()
defer pb.Stop()
assertAlive(c, w, "a", false)
assertAlive(c, w, "b", false)
// Buffer one entry to avoid blocking the watcher here.
cha := make(chan presence.Change, 1)
chb := make(chan presence.Change, 1)
w.Watch("a", cha)
w.Watch("b", chb)
// Initial events with current status.
assertChange(c, cha, presence.Change{"a", false})
assertChange(c, chb, presence.Change{"b", false})
w.StartSync()
assertNoChange(c, cha)
assertNoChange(c, chb)
c.Assert(pa.Start(), IsNil)
w.StartSync()
assertChange(c, cha, presence.Change{"a", true})
assertNoChange(c, cha)
assertNoChange(c, chb)
assertAlive(c, w, "a", true)
assertAlive(c, w, "b", false)
// Changes while the channel is out are not observed.
w.Unwatch("a", cha)
assertNoChange(c, cha)
pa.Kill()
w.Sync()
pa = presence.NewPinger(s.presence, "a")
pa.Start()
w.StartSync()
assertNoChange(c, cha)
// We can still query it manually, though.
assertAlive(c, w, "a", true)
assertAlive(c, w, "b", false)
// Initial positive event. No refresh needed.
w.Watch("a", cha)
assertChange(c, cha, presence.Change{"a", true})
c.Assert(pb.Start(), IsNil)
w.StartSync()
assertChange(c, chb, presence.Change{"b", true})
assertNoChange(c, cha)
assertNoChange(c, chb)
c.Assert(pa.Stop(), IsNil)
w.StartSync()
assertNoChange(c, cha)
assertNoChange(c, chb)
// pb is running, pa isn't.
c.Assert(pa.Kill(), IsNil)
c.Assert(pb.Kill(), IsNil)
w.StartSync()
assertChange(c, cha, presence.Change{"a", false})
assertChange(c, chb, presence.Change{"b", false})
c.Assert(w.Stop(), IsNil)
}