VOL-1905 added openolt-adapter unit tests for Main.go

Change-Id: I2cd1a58db1ab836fb6638a8bdc3eff346f72d98d
diff --git a/vendor/go.etcd.io/etcd/pkg/mock/mockserver/mockserver.go b/vendor/go.etcd.io/etcd/pkg/mock/mockserver/mockserver.go
new file mode 100644
index 0000000..59c543e
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/mock/mockserver/mockserver.go
@@ -0,0 +1,188 @@
+// Copyright 2018 The etcd 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 mockserver
+
+import (
+	"context"
+	"fmt"
+	"io/ioutil"
+	"net"
+	"os"
+	"sync"
+
+	pb "go.etcd.io/etcd/etcdserver/etcdserverpb"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/resolver"
+)
+
+// MockServer provides a mocked out grpc server of the etcdserver interface.
+type MockServer struct {
+	ln         net.Listener
+	Network    string
+	Address    string
+	GrpcServer *grpc.Server
+}
+
+func (ms *MockServer) ResolverAddress() resolver.Address {
+	switch ms.Network {
+	case "unix":
+		return resolver.Address{Addr: fmt.Sprintf("unix://%s", ms.Address)}
+	case "tcp":
+		return resolver.Address{Addr: ms.Address}
+	default:
+		panic("illegal network type: " + ms.Network)
+	}
+}
+
+// MockServers provides a cluster of mocket out gprc servers of the etcdserver interface.
+type MockServers struct {
+	mu      sync.RWMutex
+	Servers []*MockServer
+	wg      sync.WaitGroup
+}
+
+// StartMockServers creates the desired count of mock servers
+// and starts them.
+func StartMockServers(count int) (ms *MockServers, err error) {
+	return StartMockServersOnNetwork(count, "tcp")
+}
+
+// StartMockServersOnNetwork creates mock servers on either 'tcp' or 'unix' sockets.
+func StartMockServersOnNetwork(count int, network string) (ms *MockServers, err error) {
+	switch network {
+	case "tcp":
+		return startMockServersTcp(count)
+	case "unix":
+		return startMockServersUnix(count)
+	default:
+		return nil, fmt.Errorf("unsupported network type: %s", network)
+	}
+}
+
+func startMockServersTcp(count int) (ms *MockServers, err error) {
+	addrs := make([]string, 0, count)
+	for i := 0; i < count; i++ {
+		addrs = append(addrs, "localhost:0")
+	}
+	return startMockServers("tcp", addrs)
+}
+
+func startMockServersUnix(count int) (ms *MockServers, err error) {
+	dir := os.TempDir()
+	addrs := make([]string, 0, count)
+	for i := 0; i < count; i++ {
+		f, err := ioutil.TempFile(dir, "etcd-unix-so-")
+		if err != nil {
+			return nil, fmt.Errorf("failed to allocate temp file for unix socket: %v", err)
+		}
+		fn := f.Name()
+		err = os.Remove(fn)
+		if err != nil {
+			return nil, fmt.Errorf("failed to remove temp file before creating unix socket: %v", err)
+		}
+		addrs = append(addrs, fn)
+	}
+	return startMockServers("unix", addrs)
+}
+
+func startMockServers(network string, addrs []string) (ms *MockServers, err error) {
+	ms = &MockServers{
+		Servers: make([]*MockServer, len(addrs)),
+		wg:      sync.WaitGroup{},
+	}
+	defer func() {
+		if err != nil {
+			ms.Stop()
+		}
+	}()
+	for idx, addr := range addrs {
+		ln, err := net.Listen(network, addr)
+		if err != nil {
+			return nil, fmt.Errorf("failed to listen %v", err)
+		}
+		ms.Servers[idx] = &MockServer{ln: ln, Network: network, Address: ln.Addr().String()}
+		ms.StartAt(idx)
+	}
+	return ms, nil
+}
+
+// StartAt restarts mock server at given index.
+func (ms *MockServers) StartAt(idx int) (err error) {
+	ms.mu.Lock()
+	defer ms.mu.Unlock()
+
+	if ms.Servers[idx].ln == nil {
+		ms.Servers[idx].ln, err = net.Listen(ms.Servers[idx].Network, ms.Servers[idx].Address)
+		if err != nil {
+			return fmt.Errorf("failed to listen %v", err)
+		}
+	}
+
+	svr := grpc.NewServer()
+	pb.RegisterKVServer(svr, &mockKVServer{})
+	ms.Servers[idx].GrpcServer = svr
+
+	ms.wg.Add(1)
+	go func(svr *grpc.Server, l net.Listener) {
+		svr.Serve(l)
+	}(ms.Servers[idx].GrpcServer, ms.Servers[idx].ln)
+	return nil
+}
+
+// StopAt stops mock server at given index.
+func (ms *MockServers) StopAt(idx int) {
+	ms.mu.Lock()
+	defer ms.mu.Unlock()
+
+	if ms.Servers[idx].ln == nil {
+		return
+	}
+
+	ms.Servers[idx].GrpcServer.Stop()
+	ms.Servers[idx].GrpcServer = nil
+	ms.Servers[idx].ln = nil
+	ms.wg.Done()
+}
+
+// Stop stops the mock server, immediately closing all open connections and listeners.
+func (ms *MockServers) Stop() {
+	for idx := range ms.Servers {
+		ms.StopAt(idx)
+	}
+	ms.wg.Wait()
+}
+
+type mockKVServer struct{}
+
+func (m *mockKVServer) Range(context.Context, *pb.RangeRequest) (*pb.RangeResponse, error) {
+	return &pb.RangeResponse{}, nil
+}
+
+func (m *mockKVServer) Put(context.Context, *pb.PutRequest) (*pb.PutResponse, error) {
+	return &pb.PutResponse{}, nil
+}
+
+func (m *mockKVServer) DeleteRange(context.Context, *pb.DeleteRangeRequest) (*pb.DeleteRangeResponse, error) {
+	return &pb.DeleteRangeResponse{}, nil
+}
+
+func (m *mockKVServer) Txn(context.Context, *pb.TxnRequest) (*pb.TxnResponse, error) {
+	return &pb.TxnResponse{}, nil
+}
+
+func (m *mockKVServer) Compact(context.Context, *pb.CompactionRequest) (*pb.CompactionResponse, error) {
+	return &pb.CompactionResponse{}, nil
+}