[FAB-8949] Add Close() to discovery, selection services

Change-Id: I92af6c8d09140b736f03c6528ffc39ead6878e8d
Signed-off-by: Divyank Katira <Divyank.Katira@securekey.com>

Author: d1vyank

pkg/client/common/selection/dynamicselection/dynamicselection.go

@@ -8,6 +8,7 @@ package dynamicselection
 
 import (
 	"fmt"
+	"sync"
 	"time"
 
 	"github.com/hyperledger/fabric-sdk-go/pkg/util/concurrent/lazycache"
@@ -42,6 +43,8 @@ type SelectionProvider struct {
 	lbp          pgresolver.LoadBalancePolicy
 	providers    api.Providers
 	cacheTimeout time.Duration
+	refs         []*selectionService
+	refLock      sync.RWMutex
 }
 
 // Opt applies a selection provider option
@@ -114,8 +117,26 @@ func (p *SelectionProvider) CreateSelectionService(channelID string) (fab.Select
 	if err != nil {
 		return nil, errors.WithMessage(err, "Failed to create cc policy provider")
 	}
+	svc, err := newSelectionService(channelID, p.lbp, ccPolicyProvider, p.cacheTimeout)
+	if err != nil {
+		return nil, err
+	}
+
+	p.refLock.Lock()
+	p.refs = append(p.refs, svc)
+	p.refLock.Unlock()
+
+	return svc, nil
+}
+
+// Close the selection services created by this provider
+func (p *SelectionProvider) Close() {
+	p.refLock.Lock()
+	defer p.refLock.Unlock()
 
-	return newSelectionService(channelID, p.lbp, ccPolicyProvider, p.cacheTimeout)
+	for _, ref := range p.refs {
+		ref.Close()
+	}
 }
 
 func newSelectionService(channelID string, lbp pgresolver.LoadBalancePolicy, ccPolicyProvider CCPolicyProvider, cacheTimeout time.Duration) (*selectionService, error) {
@@ -159,6 +180,10 @@ func (s *selectionService) GetEndorsersForChaincode(chaincodeIDs []string, opts
 	return resolver.Resolve(params.PeerFilter).Peers(), nil
 }
 
+func (s *selectionService) Close() {
+	s.pgResolvers.Close()
+}
+
 func (s *selectionService) getPeerGroupResolver(chaincodeIDs []string) (pgresolver.PeerGroupResolver, error) {
 	value, err := s.pgResolvers.Get(newResolverKey(s.channelID, chaincodeIDs...))
 	if err != nil {

pkg/fabsdk/fabsdk.go

@@ -39,6 +39,10 @@ type options struct {
 // Option configures the SDK.
 type Option func(opts *options) error
 
+type closeable interface {
+	Close()
+}
+
 // New initializes the SDK based on the set of options provided.
 // configProvider provides the application configuration.
 func New(cp core.ConfigProvider, opts ...Option) (*FabricSDK, error) {
@@ -233,6 +237,12 @@ func initSDK(sdk *FabricSDK, config core.Config, opts []Option) error {
 
 // Close frees up caches and connections being maintained by the SDK
 func (sdk *FabricSDK) Close() {
+	if pvdr, ok := sdk.provider.DiscoveryProvider().(closeable); ok {
+		pvdr.Close()
+	}
+	if pvdr, ok := sdk.provider.SelectionProvider().(closeable); ok {
+		pvdr.Close()
+	}
 	sdk.provider.InfraProvider().Close()
 }