Polish circuit breaking and "hot spot" param flow example

Signed-off-by: Eric Zhao <sczyh16@gmail.com>

example/circuitbreaker/circuit_breaker_example.go

@@ -7,7 +7,7 @@ import (
 	"math/rand"
 	"time"
 
-	"github.com/alibaba/sentinel-golang/api"
+	sentinel "github.com/alibaba/sentinel-golang/api"
 	"github.com/alibaba/sentinel-golang/core/circuitbreaker"
 	"github.com/alibaba/sentinel-golang/util"
 )
@@ -28,45 +28,50 @@ func (s *stateChangeTestListener) OnTransformToHalfOpen(prev circuitbreaker.Stat
 }
 
 func main() {
-	err := api.InitDefault()
+	err := sentinel.InitDefault()
 	if err != nil {
 		log.Fatal(err)
 	}
 	ch := make(chan struct{})
+	// Register a state change listener so that we could observer the state change of the internal circuit breaker.
 	circuitbreaker.RegisterStateChangeListeners(&stateChangeTestListener{})
 
 	_, err = circuitbreaker.LoadRules([]circuitbreaker.Rule{
+		// Statistic time span=10s, recoveryTimeout=3s, slowRtUpperBound=50ms, maxSlowRequestRatio=50%
 		circuitbreaker.NewSlowRtRule("abc", 10000, 3000, 50, 10, 0.5),
+		// Statistic time span=10s, recoveryTimeout=3s, maxErrorRatio=50%
 		circuitbreaker.NewErrorRatioRule("abc", 10000, 3000, 10, 0.5),
 	})
 	if err != nil {
 		log.Fatal(err)
 	}
 
+	fmt.Println("Sentinel Go circuit breaking demo is running. You may see the pass/block metric in the metric log.")
 	go func() {
 		for {
-			e, b := api.Entry("abc")
+			e, b := sentinel.Entry("abc")
 			if b != nil {
-				fmt.Println("g1blocked")
+				//fmt.Println("g1blocked")
 				time.Sleep(time.Duration(rand.Uint64()%20) * time.Millisecond)
 			} else {
 				if rand.Uint64()%20 > 9 {
-					e.SetError(errors.New("biz error"))
+					// Record current invocation as error.
+					sentinel.TraceError(e, errors.New("biz error"))
 				}
-				fmt.Println("g1passed")
-				time.Sleep(time.Duration(rand.Uint64()%80) * time.Millisecond)
+				//fmt.Println("g1passed")
+				time.Sleep(time.Duration(rand.Uint64()%80+10) * time.Millisecond)
 				e.Exit()
 			}
 		}
 	}()
 	go func() {
 		for {
-			e, b := api.Entry("abc")
+			e, b := sentinel.Entry("abc")
 			if b != nil {
-				fmt.Println("g2blocked")
+				//fmt.Println("g2blocked")
 				time.Sleep(time.Duration(rand.Uint64()%20) * time.Millisecond)
 			} else {
-				fmt.Println("g2passed")
+				//fmt.Println("g2passed")
 				time.Sleep(time.Duration(rand.Uint64()%80) * time.Millisecond)
 				e.Exit()
 			}

example/circuitbreaker/sentinel.yml

@@ -0,0 +1,4 @@
+version: "v1"
+sentinel:
+  app:
+    name: sentinel-go-circuit-breaking-demo

example/freq_params_traffic/hot_params_flow_example.go → example/hotspot_param_flow/hotspot_param_flow_example.go

@@ -20,55 +20,33 @@ func main() {
 	var Resource = "test"
 
 	// We should initialize Sentinel first.
-	err := sentinel.Init("./hot-pramas-sentinel.yml")
+	err := sentinel.InitDefault()
 	if err != nil {
 		log.Fatalf("Unexpected error: %+v", err)
 	}
 
 	_, err = hotspot.LoadRules([]*hotspot.Rule{
 		{
-			Id:                "a1",
+			Id:                "1",
 			Resource:          Resource,
-			MetricType:        hotspot.Concurrency,
-			Behavior:          hotspot.Reject,
-			ParamIndex:        0,
-			Threshold:         100,
-			MaxQueueingTimeMs: 0,
-			BurstCount:        10,
-			DurationInSec:     1,
-			SpecificItems:     make(map[hotspot.SpecificValue]int64),
-		},
-		{
-			Id:                "a2",
-			Resource:          Resource,
-			MetricType:        hotspot.Concurrency,
-			Behavior:          hotspot.Reject,
+			MetricType:        hotspot.QPS,
+			ControlBehavior:   hotspot.Reject,
 			ParamIndex:        1,
-			Threshold:         100,
+			Threshold:         50,
 			MaxQueueingTimeMs: 0,
-			BurstCount:        10,
+			BurstCount:        0,
 			DurationInSec:     1,
-			SpecificItems:     make(map[hotspot.SpecificValue]int64),
+			SpecificItems: map[hotspot.SpecificValue]int64{
+				{ValKind: hotspot.KindInt, ValStr: "9"}: 0,
+			},
 		},
 		{
-			Id:                "a3",
+			Id:                "2",
 			Resource:          Resource,
-			MetricType:        hotspot.Concurrency,
-			Behavior:          hotspot.Reject,
+			MetricType:        hotspot.QPS,
+			ControlBehavior:   hotspot.Reject,
 			ParamIndex:        2,
-			Threshold:         100,
-			MaxQueueingTimeMs: 0,
-			BurstCount:        10,
-			DurationInSec:     1,
-			SpecificItems:     make(map[hotspot.SpecificValue]int64),
-		},
-		{
-			Id:                "a4",
-			Resource:          Resource,
-			MetricType:        hotspot.Concurrency,
-			Behavior:          hotspot.Reject,
-			ParamIndex:        3,
-			Threshold:         100,
+			Threshold:         50,
 			MaxQueueingTimeMs: 0,
 			BurstCount:        10,
 			DurationInSec:     1,
@@ -88,20 +66,18 @@ func main() {
 	sc.AddStatSlotLast(&stat.StatisticSlot{})
 	sc.AddStatSlotLast(&hotspot.ConcurrencyStatSlot{})
 
-	for i := 0; i < 100; i++ {
+	for i := 0; i < 10; i++ {
 		go func() {
 			for {
-				e, b := sentinel.Entry(Resource, sentinel.WithTrafficType(base.Inbound), sentinel.WithSlotChain(sc), sentinel.WithArgs(true, rand.Int()%3000, uuid.New().String(), uuid.New().String()))
+				e, b := sentinel.Entry(Resource, sentinel.WithTrafficType(base.Inbound), sentinel.WithSlotChain(sc), sentinel.WithArgs(true, rand.Uint32()%30, "sentinel", uuid.New().String()))
 				if b != nil {
 					// Blocked. We could get the block reason from the BlockError.
 					time.Sleep(time.Duration(rand.Uint64()%10) * time.Millisecond)
-					fmt.Println(util.CurrentTimeMillis(), " blocked")
-				} else if e == nil && b == nil {
-					fmt.Println("e is ni")
+					//fmt.Println(util.CurrentTimeMillis(), "blocked")
 				} else {
 					// Passed, wrap the logic here.
-					fmt.Println(util.CurrentTimeMillis(), " passed")
-					time.Sleep(time.Duration(rand.Uint64()%10) * time.Millisecond)
+					fmt.Println(util.CurrentTimeMillis(), "passed")
+					//time.Sleep(time.Duration(rand.Uint64()%10) * time.Millisecond)
 					// Be sure the entry is exited finally.
 					e.Exit()
 				}
@@ -111,21 +87,18 @@ func main() {
 	}
 
 	for {
-		e, b := sentinel.Entry(Resource, sentinel.WithTrafficType(base.Inbound), sentinel.WithSlotChain(sc), sentinel.WithArgs(true, rand.Int()%3000, uuid.New().String(), uuid.New().String()))
+		e, b := sentinel.Entry(Resource, sentinel.WithTrafficType(base.Inbound), sentinel.WithSlotChain(sc), sentinel.WithArgs(false, uint32(9), "ahas", uuid.New().String()))
 		if b != nil {
 			// Blocked. We could get the block reason from the BlockError.
 			time.Sleep(time.Duration(rand.Uint64()%10) * time.Millisecond)
-			fmt.Println(util.CurrentTimeMillis(), " blocked")
-		} else if e == nil && b == nil {
-			fmt.Println("e is ni")
+			fmt.Println(util.CurrentTimeMillis(), "blocked")
 		} else {
 			// Passed, wrap the logic here.
-			fmt.Println(util.CurrentTimeMillis(), " passed")
+			fmt.Println(util.CurrentTimeMillis(), "passed")
 			time.Sleep(time.Duration(rand.Uint64()%10) * time.Millisecond)
 
 			// Be sure the entry is exited finally.
 			e.Exit()
 		}
-
 	}
 }

example/hotspot_param_flow/sentinel.yml

@@ -0,0 +1,4 @@
+version: "v1"
+sentinel:
+  app:
+    name: sentinel-go-param-flow-demo