Outbound: One endpoint and at most one user only (#5144)

https://github.com/XTLS/Xray-core/pull/5124#issuecomment-3281091009

Fixes https://github.com/XTLS/Xray-core/pull/5124#pullrequestreview-3218097421

common/protocol/server_spec.go

@@ -1,122 +1,30 @@
 package protocol
 
 import (
-	"sync"
-	"time"
-
-	"github.com/xtls/xray-core/common/dice"
 	"github.com/xtls/xray-core/common/net"
 )
 
-type ValidationStrategy interface {
-	IsValid() bool
-	Invalidate()
-}
-
-type alwaysValidStrategy struct{}
-
-func AlwaysValid() ValidationStrategy {
-	return alwaysValidStrategy{}
-}
-
-func (alwaysValidStrategy) IsValid() bool {
-	return true
-}
-
-func (alwaysValidStrategy) Invalidate() {}
-
-type timeoutValidStrategy struct {
-	until time.Time
-}
-
-func BeforeTime(t time.Time) ValidationStrategy {
-	return &timeoutValidStrategy{
-		until: t,
-	}
-}
-
-func (s *timeoutValidStrategy) IsValid() bool {
-	return s.until.After(time.Now())
-}
-
-func (s *timeoutValidStrategy) Invalidate() {
-	s.until = time.Time{}
-}
-
 type ServerSpec struct {
-	sync.RWMutex
-	dest  net.Destination
-	users []*MemoryUser
-	valid ValidationStrategy
+	Destination  net.Destination
+	User         *MemoryUser
 }
 
-func NewServerSpec(dest net.Destination, valid ValidationStrategy, users ...*MemoryUser) *ServerSpec {
+func NewServerSpec(dest net.Destination, user *MemoryUser) *ServerSpec {
 	return &ServerSpec{
-		dest:  dest,
-		users: users,
-		valid: valid,
+		Destination: dest,
+		User:        user,
 	}
 }
 
 func NewServerSpecFromPB(spec *ServerEndpoint) (*ServerSpec, error) {
 	dest := net.TCPDestination(spec.Address.AsAddress(), net.Port(spec.Port))
-	mUsers := make([]*MemoryUser, len(spec.User))
-	for idx, u := range spec.User {
-		mUser, err := u.ToMemoryUser()
+	var dUser *MemoryUser
+	if spec.User != nil {
+		user, err := spec.User.ToMemoryUser()
 		if err != nil {
 			return nil, err
 		}
-		mUsers[idx] = mUser
+		dUser = user
 	}
-	return NewServerSpec(dest, AlwaysValid(), mUsers...), nil
-}
-
-func (s *ServerSpec) Destination() net.Destination {
-	return s.dest
-}
-
-func (s *ServerSpec) HasUser(user *MemoryUser) bool {
-	s.RLock()
-	defer s.RUnlock()
-
-	for _, u := range s.users {
-		if u.Account.Equals(user.Account) {
-			return true
-		}
-	}
-	return false
-}
-
-func (s *ServerSpec) AddUser(user *MemoryUser) {
-	if s.HasUser(user) {
-		return
-	}
-
-	s.Lock()
-	defer s.Unlock()
-
-	s.users = append(s.users, user)
-}
-
-func (s *ServerSpec) PickUser() *MemoryUser {
-	s.RLock()
-	defer s.RUnlock()
-
-	userCount := len(s.users)
-	switch userCount {
-	case 0:
-		return nil
-	case 1:
-		return s.users[0]
-	default:
-		return s.users[dice.Roll(userCount)]
-	}
-}
-
-func (s *ServerSpec) IsValid() bool {
-	return s.valid.IsValid()
-}
-
-func (s *ServerSpec) Invalidate() {
-	s.valid.Invalidate()
+	return NewServerSpec(dest, dUser), nil
 }