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Some renames in round-robin balancer
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Making a clear path for more service port changes,making this code more
comprehensible.
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@thockin
thockin committed Feb 23, 2015
1 parent 37b8c14 commit e88134f
Showing 1 changed file with 56 additions and 58 deletions.
114 changes: 56 additions & 58 deletions pkg/proxy/roundrobin.go
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Original file line number Diff line number Diff line change
Expand Up @@ -34,19 +34,18 @@ var (
ErrMissingEndpoints = errors.New("missing endpoints")
)

type sessionAffinityDetail struct {
clientIPAddress string
type affinityState struct {
clientIP string
//clientProtocol api.Protocol //not yet used
//sessionCookie string //not yet used
endpoint string
lastUsedDTTM time.Time
endpoint string
lastUsed time.Time
}

type serviceDetail struct {
name string
sessionAffinityType api.AffinityType
sessionAffinityMap map[string]*sessionAffinityDetail
stickyMaxAgeMinutes int
type affinityPolicy struct {
affinityType api.AffinityType
affinityMap map[string]*affinityState // map client IP -> affinity info
ttlMinutes int
}

// balancerKey is a string that the balancer uses to key stored state.
Expand All @@ -57,15 +56,14 @@ type LoadBalancerRR struct {
lock sync.RWMutex
endpointsMap map[balancerKey][]string
rrIndex map[balancerKey]int
serviceDtlMap map[balancerKey]serviceDetail
serviceDtlMap map[balancerKey]affinityPolicy
}

func newServiceDetail(service string, sessionAffinityType api.AffinityType, stickyMaxAgeMinutes int) *serviceDetail {
return &serviceDetail{
name: service,
sessionAffinityType: sessionAffinityType,
sessionAffinityMap: make(map[string]*sessionAffinityDetail),
stickyMaxAgeMinutes: stickyMaxAgeMinutes,
func newAffinityPolicy(affinityType api.AffinityType, ttlMinutes int) *affinityPolicy {
return &affinityPolicy{
affinityType: affinityType,
affinityMap: make(map[string]*affinityState),
ttlMinutes: ttlMinutes,
}
}

Expand All @@ -74,25 +72,25 @@ func NewLoadBalancerRR() *LoadBalancerRR {
return &LoadBalancerRR{
endpointsMap: make(map[balancerKey][]string),
rrIndex: make(map[balancerKey]int),
serviceDtlMap: make(map[balancerKey]serviceDetail),
serviceDtlMap: make(map[balancerKey]affinityPolicy),
}
}

func (lb *LoadBalancerRR) NewService(service string, sessionAffinityType api.AffinityType, stickyMaxAgeMinutes int) error {
if stickyMaxAgeMinutes == 0 {
stickyMaxAgeMinutes = 180 //default to 3 hours if not specified. Should 0 be unlimeted instead????
func (lb *LoadBalancerRR) NewService(service string, affinityType api.AffinityType, ttlMinutes int) error {
if ttlMinutes == 0 {
ttlMinutes = 180 //default to 3 hours if not specified. Should 0 be unlimeted instead????
}
if _, exists := lb.serviceDtlMap[balancerKey(service)]; !exists {
lb.serviceDtlMap[balancerKey(service)] = *newServiceDetail(service, sessionAffinityType, stickyMaxAgeMinutes)
lb.serviceDtlMap[balancerKey(service)] = *newAffinityPolicy(affinityType, ttlMinutes)
glog.V(4).Infof("NewService. Service does not exist. So I created it: %+v", lb.serviceDtlMap[balancerKey(service)])
}
return nil
}

// return true if this service detail is using some form of session affinity.
func isSessionAffinity(serviceDtl serviceDetail) bool {
// return true if this service is using some form of session affinity.
func isSessionAffinity(affinity *affinityPolicy) bool {
//Should never be empty string, but chekcing for it to be safe.
if serviceDtl.sessionAffinityType == "" || serviceDtl.sessionAffinityType == api.AffinityTypeNone {
if affinity.affinityType == "" || affinity.affinityType == api.AffinityTypeNone {
return false
}
return true
Expand All @@ -108,7 +106,7 @@ func (lb *LoadBalancerRR) NextEndpoint(service string, srcAddr net.Addr) (string
serviceDtls, exists := lb.serviceDtlMap[balancerKey(service)]
endpoints, _ := lb.endpointsMap[balancerKey(service)]
index := lb.rrIndex[balancerKey(service)]
sessionAffinityEnabled := isSessionAffinity(serviceDtls)
sessionAffinityEnabled := isSessionAffinity(&serviceDtls)

lb.lock.RUnlock()
if !exists {
Expand All @@ -121,11 +119,11 @@ func (lb *LoadBalancerRR) NextEndpoint(service string, srcAddr net.Addr) (string
if _, _, err := net.SplitHostPort(srcAddr.String()); err == nil {
ipaddr, _, _ = net.SplitHostPort(srcAddr.String())
}
sessionAffinity, exists := serviceDtls.sessionAffinityMap[ipaddr]
sessionAffinity, exists := serviceDtls.affinityMap[ipaddr]
glog.V(4).Infof("NextEndpoint. Key: %s. sessionAffinity: %+v", ipaddr, sessionAffinity)
if exists && int(time.Now().Sub(sessionAffinity.lastUsedDTTM).Minutes()) < serviceDtls.stickyMaxAgeMinutes {
if exists && int(time.Now().Sub(sessionAffinity.lastUsed).Minutes()) < serviceDtls.ttlMinutes {
endpoint := sessionAffinity.endpoint
sessionAffinity.lastUsedDTTM = time.Now()
sessionAffinity.lastUsed = time.Now()
glog.V(4).Infof("NextEndpoint. Key: %s. sessionAffinity: %+v", ipaddr, sessionAffinity)
return endpoint, nil
}
Expand All @@ -135,17 +133,17 @@ func (lb *LoadBalancerRR) NextEndpoint(service string, srcAddr net.Addr) (string
lb.rrIndex[balancerKey(service)] = (index + 1) % len(endpoints)

if sessionAffinityEnabled {
var affinity *sessionAffinityDetail
affinity, _ = lb.serviceDtlMap[balancerKey(service)].sessionAffinityMap[ipaddr]
var affinity *affinityState
affinity, _ = lb.serviceDtlMap[balancerKey(service)].affinityMap[ipaddr]
if affinity == nil {
affinity = new(sessionAffinityDetail) //&sessionAffinityDetail{ipaddr, "TCP", "", endpoint, time.Now()}
lb.serviceDtlMap[balancerKey(service)].sessionAffinityMap[ipaddr] = affinity
affinity = new(affinityState) //&affinityState{ipaddr, "TCP", "", endpoint, time.Now()}
lb.serviceDtlMap[balancerKey(service)].affinityMap[ipaddr] = affinity
}
affinity.lastUsedDTTM = time.Now()
affinity.lastUsed = time.Now()
affinity.endpoint = endpoint
affinity.clientIPAddress = ipaddr
affinity.clientIP = ipaddr

glog.V(4).Infof("NextEndpoint. New Affinity key %s: %+v", ipaddr, lb.serviceDtlMap[balancerKey(service)].sessionAffinityMap[ipaddr])
glog.V(4).Infof("NextEndpoint. New Affinity key %s: %+v", ipaddr, lb.serviceDtlMap[balancerKey(service)].affinityMap[ipaddr])
}

lb.lock.Unlock()
Expand All @@ -171,19 +169,19 @@ func filterValidEndpoints(endpoints []api.Endpoint) []string {

//remove any session affinity records associated to a particular endpoint (for example when a pod goes down).
func removeSessionAffinityByEndpoint(lb *LoadBalancerRR, service balancerKey, endpoint string) {
for _, affinityDetail := range lb.serviceDtlMap[service].sessionAffinityMap {
if affinityDetail.endpoint == endpoint {
glog.V(4).Infof("Removing client: %s from sessionAffinityMap for service: %s", affinityDetail.endpoint, service)
delete(lb.serviceDtlMap[service].sessionAffinityMap, affinityDetail.clientIPAddress)
for _, affinity := range lb.serviceDtlMap[service].affinityMap {
if affinity.endpoint == endpoint {
glog.V(4).Infof("Removing client: %s from affinityMap for service: %s", affinity.endpoint, service)
delete(lb.serviceDtlMap[service].affinityMap, affinity.clientIP)
}
}
}

//Loop through the valid endpoints and then the endpoints associated with the Load Balancer.
// Then remove any session affinity records that are not in both lists.
func updateServiceDetailMap(lb *LoadBalancerRR, service balancerKey, validEndpoints []string) {
func updateAffinityMap(lb *LoadBalancerRR, service balancerKey, newEndpoints []string) {
allEndpoints := map[string]int{}
for _, validEndpoint := range validEndpoints {
for _, validEndpoint := range newEndpoints {
allEndpoints[validEndpoint] = 1
}
for _, existingEndpoint := range lb.endpointsMap[service] {
Expand All @@ -193,35 +191,35 @@ func updateServiceDetailMap(lb *LoadBalancerRR, service balancerKey, validEndpoi
if mVal == 1 {
glog.V(3).Infof("Delete endpoint %s for service: %s", mKey, service)
removeSessionAffinityByEndpoint(lb, service, mKey)
delete(lb.serviceDtlMap[service].sessionAffinityMap, mKey)
delete(lb.serviceDtlMap[service].affinityMap, mKey)
}
}
}

// OnUpdate manages the registered service endpoints.
// Registered endpoints are updated if found in the update set or
// unregistered if missing from the update set.
func (lb *LoadBalancerRR) OnUpdate(endpoints []api.Endpoints) {
func (lb *LoadBalancerRR) OnUpdate(allEndpoints []api.Endpoints) {
registeredEndpoints := make(map[balancerKey]bool)
lb.lock.Lock()
defer lb.lock.Unlock()
// Update endpoints for services.
for _, endpoint := range endpoints {
existingEndpoints, exists := lb.endpointsMap[balancerKey(endpoint.Name)]
validEndpoints := filterValidEndpoints(endpoint.Endpoints)
if !exists || !reflect.DeepEqual(slice.SortStrings(slice.CopyStrings(existingEndpoints)), slice.SortStrings(validEndpoints)) {
glog.V(3).Infof("LoadBalancerRR: Setting endpoints for %s to %+v", endpoint.Name, endpoint.Endpoints)
updateServiceDetailMap(lb, balancerKey(endpoint.Name), validEndpoints)
for _, svcEndpoints := range allEndpoints {
curEndpoints, exists := lb.endpointsMap[balancerKey(svcEndpoints.Name)]
newEndpoints := filterValidEndpoints(svcEndpoints.Endpoints)
if !exists || !reflect.DeepEqual(slice.SortStrings(slice.CopyStrings(curEndpoints)), slice.SortStrings(newEndpoints)) {
glog.V(3).Infof("LoadBalancerRR: Setting endpoints for %s to %+v", svcEndpoints.Name, svcEndpoints.Endpoints)
updateAffinityMap(lb, balancerKey(svcEndpoints.Name), newEndpoints)
// On update can be called without NewService being called externally.
// to be safe we will call it here. A new service will only be created
// if one does not already exist.
lb.NewService(endpoint.Name, api.AffinityTypeNone, 0)
lb.endpointsMap[balancerKey(endpoint.Name)] = slice.ShuffleStrings(validEndpoints)
lb.NewService(svcEndpoints.Name, api.AffinityTypeNone, 0)
lb.endpointsMap[balancerKey(svcEndpoints.Name)] = slice.ShuffleStrings(newEndpoints)

// Reset the round-robin index.
lb.rrIndex[balancerKey(endpoint.Name)] = 0
lb.rrIndex[balancerKey(svcEndpoints.Name)] = 0
}
registeredEndpoints[balancerKey(endpoint.Name)] = true
registeredEndpoints[balancerKey(svcEndpoints.Name)] = true
}
// Remove endpoints missing from the update.
for k, v := range lb.endpointsMap {
Expand All @@ -234,11 +232,11 @@ func (lb *LoadBalancerRR) OnUpdate(endpoints []api.Endpoints) {
}

func (lb *LoadBalancerRR) CleanupStaleStickySessions(service string) {
stickyMaxAgeMinutes := lb.serviceDtlMap[balancerKey(service)].stickyMaxAgeMinutes
for key, affinityDetail := range lb.serviceDtlMap[balancerKey(service)].sessionAffinityMap {
if int(time.Now().Sub(affinityDetail.lastUsedDTTM).Minutes()) >= stickyMaxAgeMinutes {
glog.V(4).Infof("Removing client: %s from sessionAffinityMap for service: %s. Last used is greater than %d minutes....", affinityDetail.clientIPAddress, service, stickyMaxAgeMinutes)
delete(lb.serviceDtlMap[balancerKey(service)].sessionAffinityMap, key)
ttlMinutes := lb.serviceDtlMap[balancerKey(service)].ttlMinutes
for ip, affinity := range lb.serviceDtlMap[balancerKey(service)].affinityMap {
if int(time.Now().Sub(affinity.lastUsed).Minutes()) >= ttlMinutes {
glog.V(4).Infof("Removing client: %s from affinityMap for service: %s. Last used is greater than %d minutes....", affinity.clientIP, service, ttlMinutes)
delete(lb.serviceDtlMap[balancerKey(service)].affinityMap, ip)
}
}
}

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