snapshot of https://github.com/grpc/grpc-go.git (master, 2026-09-15; blobs > 131072B omitted)

internal/xds/xdsclient/requests_counter_test.go

@@ -0,0 +1,162 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed 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 xdsclient
+
+import (
+	"sync"
+	"sync/atomic"
+	"testing"
+)
+
+const testService = "test-service-name"
+
+type counterTest struct {
+	name              string
+	maxRequests       uint32
+	numRequests       uint32
+	expectedSuccesses uint32
+	expectedErrors    uint32
+}
+
+var tests = []counterTest{
+	{
+		name:              "does-not-exceed-max-requests",
+		maxRequests:       1024,
+		numRequests:       1024,
+		expectedSuccesses: 1024,
+		expectedErrors:    0,
+	},
+	{
+		name:              "exceeds-max-requests",
+		maxRequests:       32,
+		numRequests:       64,
+		expectedSuccesses: 32,
+		expectedErrors:    32,
+	},
+}
+
+func resetClusterRequestsCounter() {
+	src = &clusterRequestsCounter{
+		clusters: make(map[clusterNameAndServiceName]*ClusterRequestsCounter),
+	}
+}
+
+func testCounter(t *testing.T, test counterTest) {
+	requestsStarted := make(chan struct{})
+	requestsSent := sync.WaitGroup{}
+	requestsSent.Add(int(test.numRequests))
+	requestsDone := sync.WaitGroup{}
+	requestsDone.Add(int(test.numRequests))
+	var lastError atomic.Value
+	var successes, errors uint32
+	for i := 0; i < int(test.numRequests); i++ {
+		go func() {
+			counter := GetClusterRequestsCounter(test.name, testService)
+			defer requestsDone.Done()
+			err := counter.StartRequest(test.maxRequests)
+			if err == nil {
+				atomic.AddUint32(&successes, 1)
+			} else {
+				atomic.AddUint32(&errors, 1)
+				lastError.Store(err)
+			}
+			requestsSent.Done()
+			if err == nil {
+				<-requestsStarted
+				counter.EndRequest()
+			}
+		}()
+	}
+	requestsSent.Wait()
+	close(requestsStarted)
+	requestsDone.Wait()
+	loadedError := lastError.Load()
+	if test.expectedErrors > 0 && loadedError == nil {
+		t.Error("no error when error expected")
+	}
+	if test.expectedErrors == 0 && loadedError != nil {
+		t.Errorf("error starting request: %v", loadedError.(error))
+	}
+	// We allow the limits to be exceeded during races.
+	//
+	// But we should never over-limit, so this test fails if there are less
+	// successes than expected.
+	if successes < test.expectedSuccesses || errors > test.expectedErrors {
+		t.Errorf("unexpected number of (successes, errors), expected (%v, %v), encountered (%v, %v)", test.expectedSuccesses, test.expectedErrors, successes, errors)
+	}
+}
+
+func (s) TestRequestsCounter(t *testing.T) {
+	defer resetClusterRequestsCounter()
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			testCounter(t, test)
+		})
+	}
+}
+
+func (s) TestGetClusterRequestsCounter(t *testing.T) {
+	defer resetClusterRequestsCounter()
+	for _, test := range tests {
+		counterA := GetClusterRequestsCounter(test.name, testService)
+		counterB := GetClusterRequestsCounter(test.name, testService)
+		if counterA != counterB {
+			t.Errorf("counter %v %v != counter %v %v", counterA, *counterA, counterB, *counterB)
+		}
+	}
+}
+
+func startRequests(t *testing.T, n uint32, max uint32, counter *ClusterRequestsCounter) {
+	for i := uint32(0); i < n; i++ {
+		if err := counter.StartRequest(max); err != nil {
+			t.Fatalf("error starting initial request: %v", err)
+		}
+	}
+}
+
+func (s) TestSetMaxRequestsIncreased(t *testing.T) {
+	defer resetClusterRequestsCounter()
+	const clusterName string = "set-max-requests-increased"
+	var initialMax uint32 = 16
+
+	counter := GetClusterRequestsCounter(clusterName, testService)
+	startRequests(t, initialMax, initialMax, counter)
+	if err := counter.StartRequest(initialMax); err == nil {
+		t.Fatal("unexpected success on start request after max met")
+	}
+
+	newMax := initialMax + 1
+	if err := counter.StartRequest(newMax); err != nil {
+		t.Fatalf("unexpected error on start request after max increased: %v", err)
+	}
+}
+
+func (s) TestSetMaxRequestsDecreased(t *testing.T) {
+	defer resetClusterRequestsCounter()
+	const clusterName string = "set-max-requests-decreased"
+	var initialMax uint32 = 16
+
+	counter := GetClusterRequestsCounter(clusterName, testService)
+	startRequests(t, initialMax-1, initialMax, counter)
+
+	newMax := initialMax - 1
+	if err := counter.StartRequest(newMax); err == nil {
+		t.Fatalf("unexpected success on start request after max decreased: %v", err)
+	}
+}