diff --git a/cluster/router/condition/default_health_check.go b/cluster/router/condition/default_health_check.go
index f006d70f388a4d2f2cad998268280fc5740aa23c..ef4e2e53b1d459b7e276563fec5d87810545d09b 100644
--- a/cluster/router/condition/default_health_check.go
+++ b/cluster/router/condition/default_health_check.go
@@ -28,14 +28,19 @@ func init() {
extension.SethealthChecker(DEFAULT_HEALTH_CHECKER, NewDefaultHealthChecker)
}
-// DefaultHealthChecker is the default
+// DefaultHealthChecker is the default implementation of HealthChecker, which determines the health status of
+// the invoker based on the number of successive bad request and the current active request.
type DefaultHealthChecker struct {
+ // OutStandingRequestConutLimit
OutStandingRequestConutLimit int32
- // the circuitbreaker threshold
+ // RequestSuccessiveFailureThreshold
RequestSuccessiveFailureThreshold int32
- CircuitTrippedTimeoutFactor int32
+ // RequestSuccessiveFailureThreshold
+ CircuitTrippedTimeoutFactor int32
}
+// IsHealthy evaluates the healthy state on the given Invoker based on the number of successive bad request
+// and the current active request
func (c *DefaultHealthChecker) IsHealthy(invoker protocol.Invoker) bool {
urlStatus := protocol.GetURLStatus(invoker.GetUrl())
if c.isCircuitBreakerTripped(urlStatus) || urlStatus.GetActive() > c.OutStandingRequestConutLimit {
@@ -44,6 +49,8 @@ func (c *DefaultHealthChecker) IsHealthy(invoker protocol.Invoker) bool {
}
return true
}
+
+// isCircuitBreakerTripped determine whether the invoker is in the tripped state by the number of successive bad request
func (c *DefaultHealthChecker) isCircuitBreakerTripped(status *protocol.RPCStatus) bool {
circuitBreakerTimeout := c.getCircuitBreakerTimeout(status)
currentTime := protocol.CurrentTimeMillis()
@@ -53,6 +60,7 @@ func (c *DefaultHealthChecker) isCircuitBreakerTripped(status *protocol.RPCStatu
return circuitBreakerTimeout > currentTime
}
+// getCircuitBreakerTimeout get the timestamp recovered from tripped state
func (c *DefaultHealthChecker) getCircuitBreakerTimeout(status *protocol.RPCStatus) int64 {
sleepWindow := c.getCircuitBreakerSleepWindowTime(status)
if sleepWindow <= 0 {
@@ -61,6 +69,7 @@ func (c *DefaultHealthChecker) getCircuitBreakerTimeout(status *protocol.RPCStat
return status.GetLastRequestFailedTimestamp() + sleepWindow
}
+// getCircuitBreakerSleepWindowTime get the sleep window time of invoker
func (c *DefaultHealthChecker) getCircuitBreakerSleepWindowTime(status *protocol.RPCStatus) int64 {
successiveFailureCount := status.GetSuccessiveRequestFailureCount()
@@ -77,6 +86,7 @@ func (c *DefaultHealthChecker) getCircuitBreakerSleepWindowTime(status *protocol
return int64(sleepWindow)
}
+// NewDefaultHealthChecker constructs a new DefaultHealthChecker based on the url
func NewDefaultHealthChecker(url *common.URL) router.HealthChecker {
return &DefaultHealthChecker{
OutStandingRequestConutLimit: int32(url.GetParamInt(OUTSTANDING_REQUEST_COUNT_LIMIT_KEY, math.MaxInt32)),
diff --git a/cluster/router/condition/factory.go b/cluster/router/condition/factory.go
index 0e3d40c2f4297c5ea15757693856e95af368af7d..084903d341d3c9f715076d3dde6aa123851ec45d 100644
--- a/cluster/router/condition/factory.go
+++ b/cluster/router/condition/factory.go
@@ -27,6 +27,7 @@ import (
func init() {
extension.SetRouterFactory(constant.ConditionRouterName, newConditionRouterFactory)
extension.SetRouterFactory(constant.ConditionAppRouterName, newAppRouterFactory)
+ extension.SetRouterFactory(constant.HealthCheckRouterName, newHealthCheckRouteFactory)
}
// ConditionRouterFactory Condition router factory
diff --git a/cluster/router/condition/health_check_route.go b/cluster/router/condition/health_check_route.go
index 6cdc9b6ebc98c25bb62f782cf1bd9ebaf55e0cc6..b40d22ddb5f35e13679a215477372e6a070a46e0 100644
--- a/cluster/router/condition/health_check_route.go
+++ b/cluster/router/condition/health_check_route.go
@@ -12,12 +12,14 @@ const (
HEALTH_ROUTE_ENABLED_KEY = "health.route.enabled"
)
+// HealthCheckRouter provides a health-first routing mechanism through HealthChecker
type HealthCheckRouter struct {
url *common.URL
enabled bool
checker router.HealthChecker
}
+// NewHealthCheckRouter construct an HealthCheckRouter via url
func NewHealthCheckRouter(url *common.URL) (router.Router, error) {
r := &HealthCheckRouter{}
r.url = url
@@ -29,16 +31,19 @@ func NewHealthCheckRouter(url *common.URL) (router.Router, error) {
return r, nil
}
+// Route gets a list of healthy invoker
func (r *HealthCheckRouter) Route(invokers []protocol.Invoker, url *common.URL, invocation protocol.Invocation) []protocol.Invoker {
if !r.enabled {
return invokers
}
var healthyInvokers []protocol.Invoker
+ // Add healthy invoker to the list
for _, invoker := range invokers {
if r.checker.IsHealthy(invoker) {
healthyInvokers = append(healthyInvokers, invoker)
}
}
+ // If all Invoke are considered unhealthy, downgrade to all inovker
if len(healthyInvokers) == 0 {
logger.Warnf(" Now all invokers are unhealthy, so downgraded to all! Service: [%s]", url.ServiceKey())
return invokers
@@ -47,6 +52,7 @@ func (r *HealthCheckRouter) Route(invokers []protocol.Invoker, url *common.URL,
}
}
+// Priority
func (r *HealthCheckRouter) Priority() int64 {
return 0
}
@@ -56,6 +62,7 @@ func (r *HealthCheckRouter) URL() common.URL {
return *r.url
}
+// HealthyChecker returns the HealthChecker bound to this HealthCheckRouter
func (r *HealthCheckRouter) HealthyChecker() router.HealthChecker {
return r.checker
}
diff --git a/cluster/router/health_checker.go b/cluster/router/health_checker.go
index 58a4cbff97c9327bd762ec8ca818068f06354ffd..44e1f7ace624f17fa6b7ec755b1d1a73eb312b2c 100644
--- a/cluster/router/health_checker.go
+++ b/cluster/router/health_checker.go
@@ -4,6 +4,8 @@ import (
"github.com/apache/dubbo-go/protocol"
)
+// HealthChecker is used to determine whether the invoker is healthy or not
type HealthChecker interface {
+ // IsHealthy evaluates the healthy state on the given Invoker
IsHealthy(invoker protocol.Invoker) bool
}
diff --git a/common/constant/key.go b/common/constant/key.go
index 4536d945c333a57b59464a2d37aef78974a4b394..fc9c7af366ffe5df3d7b427677804918cbfe8209 100644
--- a/common/constant/key.go
+++ b/common/constant/key.go
@@ -159,6 +159,7 @@ const (
ConditionAppRouterName = "app"
// ListenableRouterName Specify listenable router name
ListenableRouterName = "listenable"
+ HealthCheckRouterName = "health_check"
// ConditionRouterRuleSuffix Specify condition router suffix
ConditionRouterRuleSuffix = ".condition-router"
diff --git a/common/extension/health_checker.go b/common/extension/health_checker.go
index 67deb0cc377a90ba19c152c9379b1e721b99067d..62ad1d47ff982389052347cbab7aec3a8712893a 100644
--- a/common/extension/health_checker.go
+++ b/common/extension/health_checker.go
@@ -9,10 +9,12 @@ var (
healthCheckers = make(map[string]func(url *common.URL) router.HealthChecker)
)
+// SethealthChecker set the HealthChecker with name
func SethealthChecker(name string, fcn func(url *common.URL) router.HealthChecker) {
healthCheckers[name] = fcn
}
+// GetHealthChecker get the HealthChecker with name
func GetHealthChecker(name string, url *common.URL) router.HealthChecker {
if healthCheckers[name] == nil {
panic("healthCheckers for " + name + " is not existing, make sure you have import the package.")