Merge pull request #5749 from meridional/fix-close

Fix potential panic when prometheus is watching multiple zookeeper paths
This commit is contained in:
Frederic Branczyk 2019-07-10 14:06:35 +02:00 committed by GitHub
commit dd598f906d
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@ -109,6 +109,7 @@ type Discovery struct {
sources map[string]*targetgroup.Group
updates chan treecache.ZookeeperTreeCacheEvent
pathUpdates []chan treecache.ZookeeperTreeCacheEvent
treeCaches []*treecache.ZookeeperTreeCache
parse func(data []byte, path string) (model.LabelSet, error)
@ -155,7 +156,9 @@ func NewDiscovery(
logger: logger,
}
for _, path := range paths {
sd.treeCaches = append(sd.treeCaches, treecache.NewZookeeperTreeCache(conn, path, updates, logger))
pathUpdate := make(chan treecache.ZookeeperTreeCacheEvent)
sd.pathUpdates = append(sd.pathUpdates, pathUpdate)
sd.treeCaches = append(sd.treeCaches, treecache.NewZookeeperTreeCache(conn, path, pathUpdate, logger))
}
return sd, nil
}
@ -166,12 +169,26 @@ func (d *Discovery) Run(ctx context.Context, ch chan<- []*targetgroup.Group) {
for _, tc := range d.treeCaches {
tc.Stop()
}
for _, pathUpdate := range d.pathUpdates {
// Drain event channel in case the treecache leaks goroutines otherwise.
for range d.updates {
for range pathUpdate {
}
}
d.conn.Close()
}()
for _, pathUpdate := range d.pathUpdates {
go func(update chan treecache.ZookeeperTreeCacheEvent) {
for event := range update {
select {
case d.updates <- event:
case <-ctx.Done():
return
}
}
}(pathUpdate)
}
for {
select {
case <-ctx.Done():