grpc-go/xds/internal/xdsclient/singleton_test.go

119 lines
4.0 KiB
Go

/*
*
* Copyright 2022 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 (
"context"
"testing"
"github.com/google/uuid"
"google.golang.org/grpc/internal/testutils"
"google.golang.org/grpc/internal/testutils/xds/e2e"
)
// Test that multiple New() returns the same Client. And only when the last
// client is closed, the underlying client is closed.
func (s) TestClientNewSingleton(t *testing.T) {
// Create a bootstrap configuration, place it in a file in the temp
// directory, and set the bootstrap env vars to point to it.
nodeID := uuid.New().String()
contents := e2e.DefaultBootstrapContents(t, nodeID, "non-existent-server-address")
testutils.CreateBootstrapFileForTesting(t, contents)
// Override the singleton creation hook to get notified.
origSingletonClientImplCreateHook := singletonClientImplCreateHook
singletonCreationCh := testutils.NewChannel()
singletonClientImplCreateHook = func() {
singletonCreationCh.Replace(nil)
}
defer func() { singletonClientImplCreateHook = origSingletonClientImplCreateHook }()
// Override the singleton close hook to get notified.
origSingletonClientImplCloseHook := singletonClientImplCloseHook
singletonCloseCh := testutils.NewChannel()
singletonClientImplCloseHook = func() {
singletonCloseCh.Replace(nil)
}
defer func() { singletonClientImplCloseHook = origSingletonClientImplCloseHook }()
// The first call to New() should create a new singleton client.
_, closeFunc, err := New()
if err != nil {
t.Fatalf("failed to create xDS client: %v", err)
}
ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
defer cancel()
if _, err := singletonCreationCh.Receive(ctx); err != nil {
t.Fatalf("Timeout when waiting for singleton xDS client to be created: %v", err)
}
// Calling New() again should not create new singleton client implementations.
const count = 9
closeFuncs := make([]func(), 9)
for i := 0; i < count; i++ {
func() {
_, closeFuncs[i], err = New()
if err != nil {
t.Fatalf("%d-th call to New() failed with error: %v", i, err)
}
sCtx, sCancel := context.WithTimeout(ctx, defaultTestShortTimeout)
defer sCancel()
if _, err := singletonCreationCh.Receive(sCtx); err == nil {
t.Fatalf("%d-th call to New() created a new singleton client", i)
}
}()
}
// Call Close() multiple times on each of the clients created in the above for
// loop. Close() calls are idempotent, and the underlying client
// implementation will not be closed until we release the first reference we
// acquired above, via the first call to New().
for i := 0; i < count; i++ {
func() {
closeFuncs[i]()
closeFuncs[i]()
sCtx, sCancel := context.WithTimeout(ctx, defaultTestShortTimeout)
defer sCancel()
if _, err := singletonCloseCh.Receive(sCtx); err == nil {
t.Fatal("singleton client implementation closed before all references are released")
}
}()
}
// Call the last Close(). The underlying implementation should be closed.
closeFunc()
if _, err := singletonCloseCh.Receive(ctx); err != nil {
t.Fatalf("Timeout waiting for singleton client implementation to be closed: %v", err)
}
// Calling New() again, after the previous Client was actually closed, should
// create a new one.
_, closeFunc, err = New()
if err != nil {
t.Fatalf("failed to create client: %v", err)
}
defer closeFunc()
if _, err := singletonCreationCh.Receive(ctx); err != nil {
t.Fatalf("Timeout when waiting for singleton xDS client to be created: %v", err)
}
}