Merge pull request #1045 from apache/feature/dubbo_invoker_reqnum

Imp: destroy invoker smoothly

protocol/dubbo/dubbo_invoker.go

@@ -22,13 +22,11 @@ import (
 	"strconv"
 	"strings"
 	"sync"
-	"sync/atomic"
 	"time"
 )
 
 import (
 	"github.com/opentracing/opentracing-go"
-	perrors "github.com/pkg/errors"
 )
 
 import (
@@ -41,28 +39,20 @@ import (
 	"github.com/apache/dubbo-go/remoting"
 )
 
-var (
-	// ErrNoReply
-	ErrNoReply = perrors.New("request need @response")
-	// ErrDestroyedInvoker
-	ErrDestroyedInvoker = perrors.New("request Destroyed invoker")
-)
-
 var (
 	attachmentKey = []string{constant.INTERFACE_KEY, constant.GROUP_KEY, constant.TOKEN_KEY, constant.TIMEOUT_KEY,
 		constant.VERSION_KEY}
 )
 
-// DubboInvoker is implement of protocol.Invoker. A dubboInvoker refer to one service and ip.
+// DubboInvoker is implement of protocol.Invoker. A dubboInvoker refers to one service and ip.
 type DubboInvoker struct {
 	protocol.BaseInvoker
 	// the exchange layer, it is focus on network communication.
-	client   *remoting.ExchangeClient
-	quitOnce sync.Once
+	clientGuard *sync.RWMutex
+	client      *remoting.ExchangeClient
+	quitOnce    sync.Once
 	// timeout for service(interface) level.
 	timeout time.Duration
-	// Used to record the number of requests. -1 represent this DubboInvoker is destroyed
-	reqNum int64
 }
 
 // NewDubboInvoker constructor
@@ -73,12 +63,28 @@ func NewDubboInvoker(url *common.URL, client *remoting.ExchangeClient) *DubboInv
 	if t, err := time.ParseDuration(requestTimeoutStr); err == nil {
 		requestTimeout = t
 	}
-	return &DubboInvoker{
+	di := &DubboInvoker{
 		BaseInvoker: *protocol.NewBaseInvoker(url),
+		clientGuard: &sync.RWMutex{},
 		client:      client,
-		reqNum:      0,
 		timeout:     requestTimeout,
 	}
+
+	return di
+}
+
+func (di *DubboInvoker) setClient(client *remoting.ExchangeClient) {
+	di.clientGuard.Lock()
+	defer di.clientGuard.Unlock()
+
+	di.client = client
+}
+
+func (di *DubboInvoker) getClient() *remoting.ExchangeClient {
+	di.clientGuard.RLock()
+	defer di.clientGuard.RUnlock()
+
+	return di.client
 }
 
 // Invoke call remoting.
@@ -87,15 +93,30 @@ func (di *DubboInvoker) Invoke(ctx context.Context, invocation protocol.Invocati
 		err    error
 		result protocol.RPCResult
 	)
-	if atomic.LoadInt64(&di.reqNum) < 0 {
+	if !di.BaseInvoker.IsAvailable() {
 		// Generally, the case will not happen, because the invoker has been removed
 		// from the invoker list before destroy,so no new request will enter the destroyed invoker
 		logger.Warnf("this dubboInvoker is destroyed")
-		result.Err = ErrDestroyedInvoker
+		result.Err = protocol.ErrDestroyedInvoker
+		return &result
+	}
+
+	di.clientGuard.RLock()
+	defer di.clientGuard.RUnlock()
+
+	if di.client == nil {
+		result.Err = protocol.ErrClientClosed
+		logger.Debugf("result.Err: %v", result.Err)
+		return &result
+	}
+
+	if !di.BaseInvoker.IsAvailable() {
+		// Generally, the case will not happen, because the invoker has been removed
+		// from the invoker list before destroy,so no new request will enter the destroyed invoker
+		logger.Warnf("this dubboInvoker is destroying")
+		result.Err = protocol.ErrDestroyedInvoker
 		return &result
 	}
-	atomic.AddInt64(&(di.reqNum), 1)
-	defer atomic.AddInt64(&(di.reqNum), -1)
 
 	inv := invocation.(*invocation_impl.RPCInvocation)
 	// init param
@@ -125,14 +146,13 @@ func (di *DubboInvoker) Invoke(ctx context.Context, invocation protocol.Invocati
 	timeout := di.getTimeout(inv)
 	if async {
 		if callBack, ok := inv.CallBack().(func(response common.CallbackResponse)); ok {
-			//result.Err = di.client.AsyncCall(NewRequest(url.Location, url, inv.MethodName(), inv.Arguments(), inv.Attachments()), callBack, response)
 			result.Err = di.client.AsyncRequest(&invocation, url, timeout, callBack, rest)
 		} else {
 			result.Err = di.client.Send(&invocation, url, timeout)
 		}
 	} else {
 		if inv.Reply() == nil {
-			result.Err = ErrNoReply
+			result.Err = protocol.ErrNoReply
 		} else {
 			result.Err = di.client.Request(&invocation, url, timeout, rest)
 		}
@@ -162,27 +182,23 @@ func (di *DubboInvoker) getTimeout(invocation *invocation_impl.RPCInvocation) ti
 }
 
 func (di *DubboInvoker) IsAvailable() bool {
-	return di.client.IsAvailable()
+	client := di.getClient()
+	if client != nil {
+		return client.IsAvailable()
+	}
+
+	return false
 }
 
 // Destroy destroy dubbo client invoker.
 func (di *DubboInvoker) Destroy() {
 	di.quitOnce.Do(func() {
-		for {
-			if di.reqNum == 0 {
-				di.reqNum = -1
-				logger.Infof("dubboInvoker is destroyed,url:{%s}", di.GetUrl().Key())
-				di.BaseInvoker.Destroy()
-				if di.client != nil {
-					di.client.Close()
-					di.client = nil
-				}
-				break
-			}
-			logger.Warnf("DubboInvoker is to be destroyed, wait {%v} req end,url:{%s}", di.reqNum, di.GetUrl().Key())
-			time.Sleep(1 * time.Second)
+		di.BaseInvoker.Destroy()
+		client := di.getClient()
+		if client != nil {
+			di.setClient(nil)
+			client.Close()
 		}
-
 	})
 }
 

protocol/grpc/grpc_invoker.go

@@ -24,40 +24,82 @@ import (
 )
 
 import (
+	hessian2 "github.com/apache/dubbo-go-hessian2"
 	"github.com/pkg/errors"
 	"google.golang.org/grpc/connectivity"
 )
 
 import (
-	hessian2 "github.com/apache/dubbo-go-hessian2"
-
 	"github.com/apache/dubbo-go/common"
+	"github.com/apache/dubbo-go/common/logger"
 	"github.com/apache/dubbo-go/protocol"
 )
 
-var errNoReply = errors.New("request need @response")
+var (
+	errNoReply = errors.New("request need @response")
+)
 
 // nolint
 type GrpcInvoker struct {
 	protocol.BaseInvoker
-	quitOnce sync.Once
-	client   *Client
+	quitOnce    sync.Once
+	clientGuard *sync.RWMutex
+	client      *Client
 }
 
 // NewGrpcInvoker returns a Grpc invoker instance
 func NewGrpcInvoker(url *common.URL, client *Client) *GrpcInvoker {
 	return &GrpcInvoker{
 		BaseInvoker: *protocol.NewBaseInvoker(url),
+		clientGuard: &sync.RWMutex{},
 		client:      client,
 	}
 }
 
+func (gi *GrpcInvoker) setClient(client *Client) {
+	gi.clientGuard.Lock()
+	defer gi.clientGuard.Unlock()
+
+	gi.client = client
+}
+
+func (gi *GrpcInvoker) getClient() *Client {
+	gi.clientGuard.RLock()
+	defer gi.clientGuard.RUnlock()
+
+	return gi.client
+}
+
 // Invoke is used to call service method by invocation
 func (gi *GrpcInvoker) Invoke(ctx context.Context, invocation protocol.Invocation) protocol.Result {
 	var (
 		result protocol.RPCResult
 	)
 
+	if !gi.BaseInvoker.IsAvailable() {
+		// Generally, the case will not happen, because the invoker has been removed
+		// from the invoker list before destroy,so no new request will enter the destroyed invoker
+		logger.Warnf("this grpcInvoker is destroyed")
+		result.Err = protocol.ErrDestroyedInvoker
+		return &result
+	}
+
+	gi.clientGuard.RLock()
+	defer gi.clientGuard.RUnlock()
+
+	if gi.client == nil {
+		result.Err = protocol.ErrClientClosed
+		return &result
+	}
+
+	if !gi.BaseInvoker.IsAvailable() {
+		// Generally, the case will not happen, because the invoker has been removed
+		// from the invoker list before destroy,so no new request will enter the destroyed invoker
+		logger.Warnf("this grpcInvoker is destroying")
+		result.Err = protocol.ErrDestroyedInvoker
+		return &result
+	}
+
 	if invocation.Reply() == nil {
 		result.Err = errNoReply
 	}
@@ -83,21 +125,32 @@ func (gi *GrpcInvoker) Invoke(ctx context.Context, invocation protocol.Invocatio
 
 // IsAvailable get available status
 func (gi *GrpcInvoker) IsAvailable() bool {
-	return gi.BaseInvoker.IsAvailable() && gi.client.GetState() != connectivity.Shutdown
+	client := gi.getClient()
+	if client != nil {
+		return gi.BaseInvoker.IsAvailable() && client.GetState() != connectivity.Shutdown
+	}
+
+	return false
 }
 
 // IsDestroyed get destroyed status
 func (gi *GrpcInvoker) IsDestroyed() bool {
-	return gi.BaseInvoker.IsDestroyed() && gi.client.GetState() == connectivity.Shutdown
+	client := gi.getClient()
+	if client != nil {
+		return gi.BaseInvoker.IsDestroyed() && client.GetState() == connectivity.Shutdown
+	}
+
+	return false
 }
 
 // Destroy will destroy gRPC's invoker and client, so it is only called once
 func (gi *GrpcInvoker) Destroy() {
 	gi.quitOnce.Do(func() {
 		gi.BaseInvoker.Destroy()
-
-		if gi.client != nil {
-			_ = gi.client.Close()
+		client := gi.getClient()
+		if client != nil {
+			gi.setClient(nil)
+			client.Close()
 		}
 	})
 }

protocol/invoker.go

@@ -21,11 +21,25 @@ import (
 	"context"
 )
 
+import (
+	perrors "github.com/pkg/errors"
+	uatomic "go.uber.org/atomic"
+)
+
 import (
 	"github.com/apache/dubbo-go/common"
 	"github.com/apache/dubbo-go/common/logger"
 )
 
+var (
+	// ErrClientClosed means client has clossed.
+	ErrClientClosed = perrors.New("remoting client has closed")
+	// ErrNoReply
+	ErrNoReply = perrors.New("request need @response")
+	// ErrDestroyedInvoker
+	ErrDestroyedInvoker = perrors.New("request Destroyed invoker")
+)
+
 // Invoker the service invocation interface for the consumer
 //go:generate mockgen -source invoker.go -destination mock/mock_invoker.go  -self_package github.com/apache/dubbo-go/protocol/mock --package mock  Invoker
 // Extension - Invoker
@@ -42,17 +56,19 @@ type Invoker interface {
 // BaseInvoker provides default invoker implement
 type BaseInvoker struct {
 	url       *common.URL
-	available bool
-	destroyed bool
+	available uatomic.Bool
+	destroyed uatomic.Bool
 }
 
 // NewBaseInvoker creates a new BaseInvoker
 func NewBaseInvoker(url *common.URL) *BaseInvoker {
-	return &BaseInvoker{
-		url:       url,
-		available: true,
-		destroyed: false,
+	ivk := &BaseInvoker{
+		url: url,
 	}
+	ivk.available.Store(true)
+	ivk.destroyed.Store(false)
+
+	return ivk
 }
 
 // GetUrl gets base invoker URL
@@ -62,12 +78,12 @@ func (bi *BaseInvoker) GetUrl() *common.URL {
 
 // IsAvailable gets available flag
 func (bi *BaseInvoker) IsAvailable() bool {
-	return bi.available
+	return bi.available.Load()
 }
 
 // IsDestroyed gets destroyed flag
 func (bi *BaseInvoker) IsDestroyed() bool {
-	return bi.destroyed
+	return bi.destroyed.Load()
 }
 
 // Invoke provides default invoker implement
@@ -77,7 +93,7 @@ func (bi *BaseInvoker) Invoke(context context.Context, invocation Invocation) Re
 
 // Destroy changes available and destroyed flag
 func (bi *BaseInvoker) Destroy() {
-	logger.Infof("Destroy invoker: %s", bi.GetUrl().String())
-	bi.destroyed = true
-	bi.available = false
+	logger.Infof("Destroy invoker: %s", bi.GetUrl())
+	bi.destroyed.Store(true)
+	bi.available.Store(false)
 }