xdsclient: create LRSClient at time of initialisation

xds/internal/xdsclient/clientimpl.go

@@ -130,6 +130,15 @@ func newClientImpl(config *bootstrap.Config, metricsRecorder estats.MetricsRecor
 		return nil, err
 	}
 	c := &clientImpl{XDSClient: client, xdsClientConfig: gConfig, bootstrapConfig: config, target: target, refCount: 1}
+	lrsC, err := lrsclient.New(lrsclient.Config{
+		Node:             c.xdsClientConfig.Node,
+		TransportBuilder: c.xdsClientConfig.TransportBuilder,
+	})
+	if err != nil {
+		c.logger.Warningf("Failed to create an lrs client to the management server to report load: %v", err)
+		return nil, err
+	}
+	c.lrsClient = lrsC
 	c.logger = prefixLogger(c)
 	return c, nil
 }

xds/internal/xdsclient/clientimpl_loadreport.go

@@ -33,15 +33,8 @@ import (
 // It returns a lrsclient.LoadStore for the user to report loads.
 func (c *clientImpl) ReportLoad(server *bootstrap.ServerConfig) (*lrsclient.LoadStore, func(context.Context)) {
 	if c.lrsClient == nil {
-		lrsC, err := lrsclient.New(lrsclient.Config{
-			Node:             c.xdsClientConfig.Node,
-			TransportBuilder: c.xdsClientConfig.TransportBuilder,
-		})
-		if err != nil {
-			c.logger.Warningf("Failed to create an lrs client to the management server to report load: %v", server, err)
-			return nil, func(context.Context) {}
-		}
-		c.lrsClient = lrsC
+		c.logger.Warningf("lrs Client not found")
+		return nil, func(context.Context) {}
 	}
 
 	load, err := c.lrsClient.ReportLoad(clients.ServerIdentifier{

xds/internal/xdsclient/tests/loadreport_test.go

@@ -23,6 +23,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"net"
+	"sync"
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
@@ -437,3 +438,39 @@ func (s) TestReportLoad_StreamCreation(t *testing.T) {
 	defer sCancel3()
 	cancel3(sCtx3)
 }
+
+// TestConcurrentReportLoad verifies that the client can safely handle concurrent
+// requests to initiate load reporting streams. It launches multiple goroutines
+// that all call client.ReportLoad simultaneously.
+func (s) TestConcurrentReportLoad(t *testing.T) {
+	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
+	defer cancel()
+
+	// Create a management server that serves LRS.
+	mgmtServer := e2e.StartManagementServer(t, e2e.ManagementServerOptions{SupportLoadReportingService: true})
+
+	// Create an xDS client with bootstrap pointing to the above server.
+	nodeID := uuid.New().String()
+	bc := e2e.DefaultBootstrapContents(t, nodeID, mgmtServer.Address)
+	client := createXDSClient(t, bc)
+
+	serverConfig, err := bootstrap.ServerConfigForTesting(bootstrap.ServerConfigTestingOptions{URI: mgmtServer.Address})
+	if err != nil {
+		t.Fatalf("Failed to create server config for testing: %v", err)
+	}
+	// Call ReportLoad() concurrently from multiple go routines.
+	var wg sync.WaitGroup
+	const numGoroutines = 10
+	wg.Add(numGoroutines)
+	for i := 0; i < numGoroutines; i++ {
+		go func() {
+			defer wg.Done()
+			store, cancelStore := client.ReportLoad(serverConfig)
+			if store == nil {
+				t.Errorf("ReportLoad() got nil store, want non-nil")
+			}
+			defer cancelStore(ctx)
+		}()
+	}
+	wg.Wait()
+}