// Test public interface
func doTestIndex(t *testing.T, indexer Indexer) {
mkObj := func(id string, val string) testStoreObject {
return testStoreObject{id: id, val: val}
}
// Test Index
expected := map[string]sets.String{}
expected["b"] = sets.NewString("a", "c")
expected["f"] = sets.NewString("e")
expected["h"] = sets.NewString("g")
indexer.Add(mkObj("a", "b"))
indexer.Add(mkObj("c", "b"))
indexer.Add(mkObj("e", "f"))
indexer.Add(mkObj("g", "h"))
{
for k, v := range expected {
found := sets.String{}
indexResults, err := indexer.Index("by_val", mkObj("", k))
if err != nil {
t.Errorf("Unexpected error %v", err)
}
for _, item := range indexResults {
found.Insert(item.(testStoreObject).id)
}
items := v.List()
if !found.HasAll(items...) {
t.Errorf("missing items, index %s, expected %v but found %v", k, items, found.List())
}
}
}
}
// ChooseZone implements our heuristics for choosing a zone for volume creation based on the volume name
// Volumes are generally round-robin-ed across all active zones, using the hash of the PVC Name.
// However, if the PVCName ends with `-<integer>`, we will hash the prefix, and then add the integer to the hash.
// This means that a PetSet's volumes (`claimname-petsetname-id`) will spread across available zones,
// assuming the id values are consecutive.
func ChooseZoneForVolume(zones sets.String, pvcName string) string {
// We create the volume in a zone determined by the name
// Eventually the scheduler will coordinate placement into an available zone
var hash uint32
var index uint32
if pvcName == "" {
// We should always be called with a name; this shouldn't happen
glog.Warningf("No name defined during volume create; choosing random zone")
hash = rand.Uint32()
} else {
hashString := pvcName
// Heuristic to make sure that volumes in a PetSet are spread across zones
// PetSet PVCs are (currently) named ClaimName-PetSetName-Id,
// where Id is an integer index
lastDash := strings.LastIndexByte(pvcName, '-')
if lastDash != -1 {
petIDString := pvcName[lastDash+1:]
petID, err := strconv.ParseUint(petIDString, 10, 32)
if err == nil {
// Offset by the pet id, so we round-robin across zones
index = uint32(petID)
// We still hash the volume name, but only the base
hashString = pvcName[:lastDash]
glog.V(2).Infof("Detected PetSet-style volume name %q; index=%d", pvcName, index)
}
}
// We hash the (base) volume name, so we don't bias towards the first N zones
h := fnv.New32()
h.Write([]byte(hashString))
hash = h.Sum32()
}
// Zones.List returns zones in a consistent order (sorted)
// We do have a potential failure case where volumes will not be properly spread,
// if the set of zones changes during PetSet volume creation. However, this is
// probably relatively unlikely because we expect the set of zones to be essentially
// static for clusters.
// Hopefully we can address this problem if/when we do full scheduler integration of
// PVC placement (which could also e.g. avoid putting volumes in overloaded or
// unhealthy zones)
zoneSlice := zones.List()
zone := zoneSlice[(hash+index)%uint32(len(zoneSlice))]
glog.V(2).Infof("Creating volume for PVC %q; chose zone=%q from zones=%q", pvcName, zone, zoneSlice)
return zone
}
func CheckSetEq(lhs, rhs sets.String) bool {
return lhs.HasAll(rhs.List()...) && rhs.HasAll(lhs.List()...)
}
