add healthcheck router

cluster/router/health_checker.go

@@ -0,0 +1,28 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package router
+
+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
+}

cluster/router/healthcheck/default_health_check.go

@@ -0,0 +1,117 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package healthcheck
+
+import (
+	"math"
+)
+
+import (
+	"github.com/apache/dubbo-go/cluster/router"
+	"github.com/apache/dubbo-go/common"
+	"github.com/apache/dubbo-go/common/constant"
+	"github.com/apache/dubbo-go/common/extension"
+	"github.com/apache/dubbo-go/common/logger"
+	"github.com/apache/dubbo-go/protocol"
+)
+
+func init() {
+	extension.SethealthChecker(constant.DEFAULT_HEALTH_CHECKER, NewDefaultHealthChecker)
+}
+
+// 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
+	// requestSuccessiveFailureThreshold
+	requestSuccessiveFailureThreshold 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.GetOutStandingRequestConutLimit() {
+		logger.Debugf("Invoker [%s] is currently in circuitbreaker tripped state", invoker.GetUrl().Key())
+		return false
+	}
+	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()
+	if circuitBreakerTimeout <= 0 {
+		return false
+	}
+	return circuitBreakerTimeout > currentTime
+}
+
+// getCircuitBreakerTimeout get the timestamp recovered from tripped state, the unit is millisecond
+func (c *DefaultHealthChecker) getCircuitBreakerTimeout(status *protocol.RPCStatus) int64 {
+	sleepWindow := c.getCircuitBreakerSleepWindowTime(status)
+	if sleepWindow <= 0 {
+		return 0
+	}
+	return status.GetLastRequestFailedTimestamp() + sleepWindow
+}
+
+// getCircuitBreakerSleepWindowTime get the sleep window time of invoker, the unit is millisecond
+func (c *DefaultHealthChecker) getCircuitBreakerSleepWindowTime(status *protocol.RPCStatus) int64 {
+
+	successiveFailureCount := status.GetSuccessiveRequestFailureCount()
+	diff := successiveFailureCount - c.GetRequestSuccessiveFailureThreshold()
+	if diff < 0 {
+		return 0
+	} else if diff > constant.DEFAULT_SUCCESSIVE_FAILED_REQUEST_MAX_DIFF {
+		diff = constant.DEFAULT_SUCCESSIVE_FAILED_REQUEST_MAX_DIFF
+	}
+	sleepWindow := (1 << diff) * c.GetCircuitTrippedTimeoutFactor()
+	if sleepWindow > constant.MAX_CIRCUIT_TRIPPED_TIMEOUT_IN_MS {
+		sleepWindow = constant.MAX_CIRCUIT_TRIPPED_TIMEOUT_IN_MS
+	}
+	return int64(sleepWindow)
+}
+
+// GetOutStandingRequestConutLimit return the requestSuccessiveFailureThreshold bound to this DefaultHealthChecker
+func (c *DefaultHealthChecker) GetRequestSuccessiveFailureThreshold() int32 {
+	return c.requestSuccessiveFailureThreshold
+}
+
+// GetOutStandingRequestConutLimit return the circuitTrippedTimeoutFactor bound to this DefaultHealthChecker
+func (c *DefaultHealthChecker) GetCircuitTrippedTimeoutFactor() int32 {
+	return c.circuitTrippedTimeoutFactor
+}
+
+// GetOutStandingRequestConutLimit return the outStandingRequestConutLimit bound to this DefaultHealthChecker
+func (c *DefaultHealthChecker) GetOutStandingRequestConutLimit() int32 {
+	return c.outStandingRequestConutLimit
+}
+
+// NewDefaultHealthChecker constructs a new DefaultHealthChecker based on the url
+func NewDefaultHealthChecker(url *common.URL) router.HealthChecker {
+	return &DefaultHealthChecker{
+		outStandingRequestConutLimit:      int32(url.GetParamInt(constant.OUTSTANDING_REQUEST_COUNT_LIMIT_KEY, math.MaxInt32)),
+		requestSuccessiveFailureThreshold: int32(url.GetParamInt(constant.SUCCESSIVE_FAILED_REQUEST_THRESHOLD_KEY, constant.DEFAULT_SUCCESSIVE_FAILED_REQUEST_MAX_DIFF)),
+		circuitTrippedTimeoutFactor:       int32(url.GetParamInt(constant.CIRCUIT_TRIPPED_TIMEOUT_FACTOR_KEY, constant.DEFAULT_CIRCUIT_TRIPPED_TIMEOUT_FACTOR)),
+	}
+}

cluster/router/healthcheck/default_health_check_test.go

@@ -0,0 +1,157 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package healthcheck
+
+import (
+	"math"
+	"testing"
+)
+
+import (
+	"github.com/stretchr/testify/assert"
+)
+
+import (
+	"github.com/apache/dubbo-go/common"
+	"github.com/apache/dubbo-go/common/constant"
+	"github.com/apache/dubbo-go/protocol"
+)
+
+func TestDefaultHealthChecker_IsHealthy(t *testing.T) {
+
+	defer protocol.CleanAllStatus()
+	url, _ := common.NewURL("dubbo://192.168.10.10:20000/com.ikurento.user.UserProvider")
+	hc := NewDefaultHealthChecker(&url).(*DefaultHealthChecker)
+	invoker := NewMockInvoker(url, 1)
+	healthy := hc.IsHealthy(invoker)
+	assert.True(t, healthy)
+
+	url.SetParam(constant.OUTSTANDING_REQUEST_COUNT_LIMIT_KEY, "10")
+	url.SetParam(constant.SUCCESSIVE_FAILED_REQUEST_THRESHOLD_KEY, "100")
+	// fake the outgoing request
+	for i := 0; i < 11; i++ {
+		request(url, "test", 0, true, false)
+	}
+	hc = NewDefaultHealthChecker(&url).(*DefaultHealthChecker)
+	healthy = hc.IsHealthy(invoker)
+	// the outgoing request is more than OUTSTANDING_REQUEST_COUNT_LIMIT, go to unhealthy
+	assert.False(t, hc.IsHealthy(invoker))
+
+	// successive failed count is more than constant.SUCCESSIVE_FAILED_REQUEST_THRESHOLD_KEY, go to unhealthy
+	for i := 0; i < 11; i++ {
+		request(url, "test", 0, false, false)
+	}
+	url.SetParam(constant.SUCCESSIVE_FAILED_REQUEST_THRESHOLD_KEY, "10")
+	url.SetParam(constant.OUTSTANDING_REQUEST_COUNT_LIMIT_KEY, "1000")
+	hc = NewDefaultHealthChecker(&url).(*DefaultHealthChecker)
+	healthy = hc.IsHealthy(invoker)
+	assert.False(t, hc.IsHealthy(invoker))
+
+	// reset successive failed count and go to healthy
+	request(url, "test", 0, false, true)
+	healthy = hc.IsHealthy(invoker)
+	assert.True(t, hc.IsHealthy(invoker))
+}
+
+func TestDefaultHealthChecker_getCircuitBreakerSleepWindowTime(t *testing.T) {
+	defer protocol.CleanAllStatus()
+	url, _ := common.NewURL("dubbo://192.168.10.10:20000/com.ikurento.user.UserProvider")
+	defaultHc := NewDefaultHealthChecker(&url).(*DefaultHealthChecker)
+	// Increase the number of failed requests
+	for i := 0; i < 100; i++ {
+		request(url, "test", 1, false, false)
+	}
+	sleepWindowTime := defaultHc.getCircuitBreakerSleepWindowTime(protocol.GetURLStatus(url))
+	assert.True(t, sleepWindowTime == constant.MAX_CIRCUIT_TRIPPED_TIMEOUT_IN_MS)
+
+	// Adjust the threshold size to 1000
+	url.SetParam(constant.SUCCESSIVE_FAILED_REQUEST_THRESHOLD_KEY, "1000")
+	sleepWindowTime = NewDefaultHealthChecker(&url).(*DefaultHealthChecker).getCircuitBreakerSleepWindowTime(protocol.GetURLStatus(url))
+	assert.True(t, sleepWindowTime == 0)
+
+	url1, _ := common.NewURL("dubbo://192.168.10.11:20000/com.ikurento.user.UserProvider")
+	sleepWindowTime = defaultHc.getCircuitBreakerSleepWindowTime(protocol.GetURLStatus(url1))
+	assert.True(t, sleepWindowTime == 0)
+	request(url1, "test", 1, false, false)
+	request(url1, "test", 1, false, false)
+	request(url1, "test", 1, false, false)
+	request(url1, "test", 1, false, false)
+	request(url1, "test", 1, false, false)
+	request(url1, "test", 1, false, false)
+	sleepWindowTime = defaultHc.getCircuitBreakerSleepWindowTime(protocol.GetURLStatus(url1))
+	assert.True(t, sleepWindowTime > 0 && sleepWindowTime < constant.MAX_CIRCUIT_TRIPPED_TIMEOUT_IN_MS)
+}
+
+func TestDefaultHealthChecker_getCircuitBreakerTimeout(t *testing.T) {
+	defer protocol.CleanAllStatus()
+	url, _ := common.NewURL("dubbo://192.168.10.10:20000/com.ikurento.user.UserProvider")
+	defaultHc := NewDefaultHealthChecker(&url).(*DefaultHealthChecker)
+	timeout := defaultHc.getCircuitBreakerTimeout(protocol.GetURLStatus(url))
+	assert.True(t, timeout == 0)
+	url1, _ := common.NewURL("dubbo://192.168.10.11:20000/com.ikurento.user.UserProvider")
+	request(url1, "test", 1, false, false)
+	request(url1, "test", 1, false, false)
+	request(url1, "test", 1, false, false)
+	request(url1, "test", 1, false, false)
+	request(url1, "test", 1, false, false)
+	request(url1, "test", 1, false, false)
+	timeout = defaultHc.getCircuitBreakerTimeout(protocol.GetURLStatus(url1))
+	// timeout must after the current time
+	assert.True(t, timeout > protocol.CurrentTimeMillis())
+
+}
+
+func TestDefaultHealthChecker_isCircuitBreakerTripped(t *testing.T) {
+	defer protocol.CleanAllStatus()
+	url, _ := common.NewURL("dubbo://192.168.10.10:20000/com.ikurento.user.UserProvider")
+	defaultHc := NewDefaultHealthChecker(&url).(*DefaultHealthChecker)
+	status := protocol.GetURLStatus(url)
+	tripped := defaultHc.isCircuitBreakerTripped(status)
+	assert.False(t, tripped)
+	// Increase the number of failed requests
+	for i := 0; i < 100; i++ {
+		request(url, "test", 1, false, false)
+	}
+	tripped = defaultHc.isCircuitBreakerTripped(protocol.GetURLStatus(url))
+	assert.True(t, tripped)
+
+}
+
+func TestNewDefaultHealthChecker(t *testing.T) {
+	defer protocol.CleanAllStatus()
+	url, _ := common.NewURL("dubbo://192.168.10.10:20000/com.ikurento.user.UserProvider")
+	defaultHc := NewDefaultHealthChecker(&url).(*DefaultHealthChecker)
+	assert.NotNil(t, defaultHc)
+	assert.Equal(t, defaultHc.outStandingRequestConutLimit, int32(math.MaxInt32))
+	assert.Equal(t, defaultHc.requestSuccessiveFailureThreshold, int32(constant.DEFAULT_SUCCESSIVE_FAILED_REQUEST_MAX_DIFF))
+
+	url1, _ := common.NewURL("dubbo://192.168.10.10:20000/com.ikurento.user.UserProvider")
+	url1.SetParam(constant.OUTSTANDING_REQUEST_COUNT_LIMIT_KEY, "10")
+	url1.SetParam(constant.SUCCESSIVE_FAILED_REQUEST_THRESHOLD_KEY, "10")
+	nondefaultHc := NewDefaultHealthChecker(&url1).(*DefaultHealthChecker)
+	assert.NotNil(t, nondefaultHc)
+	assert.Equal(t, nondefaultHc.outStandingRequestConutLimit, int32(10))
+	assert.Equal(t, nondefaultHc.requestSuccessiveFailureThreshold, int32(10))
+}
+
+func request(url common.URL, method string, elapsed int64, active, succeeded bool) {
+	protocol.BeginCount(url, method)
+	if !active {
+		protocol.EndCount(url, method, elapsed, succeeded)
+	}
+}

cluster/router/healthcheck/factory.go

@@ -0,0 +1,43 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package healthcheck
+
+import (
+	"github.com/apache/dubbo-go/cluster/router"
+	"github.com/apache/dubbo-go/common"
+	"github.com/apache/dubbo-go/common/constant"
+	"github.com/apache/dubbo-go/common/extension"
+)
+
+func init() {
+	extension.SetRouterFactory(constant.HealthCheckRouterName, newHealthCheckRouteFactory)
+}
+
+// HealthCheckRouteFactory
+type HealthCheckRouteFactory struct {
+}
+
+// newHealthCheckRouteFactory construct a new HealthCheckRouteFactory
+func newHealthCheckRouteFactory() router.RouterFactory {
+	return &HealthCheckRouteFactory{}
+}
+
+// NewRouter construct a new NewHealthCheckRouter via url
+func (f *HealthCheckRouteFactory) NewRouter(url *common.URL) (router.Router, error) {
+	return NewHealthCheckRouter(url)
+}