session save & load from a file. (#38)

dev/start

@@ -40,6 +40,7 @@ docker run --rm -it \
     -e "NEKO_WEBRTC_UDPMUX=${NEKO_MUX}" \
     -e "NEKO_WEBRTC_TCPMUX=${NEKO_MUX}" \
     -e "NEKO_WEBRTC_NAT1TO1=${NEKO_NAT1TO1}" \
+    -e "NEKO_SESSION_FILE=/home/neko/sessions.txt" \
     -v "${PWD}/runtime/config.yml:/etc/neko/neko.yml" \
     -e "NEKO_DEBUG=1" \
     neko_server_app:latest;

internal/config/session.go

@@ -8,6 +8,8 @@ import (
 )
 
 type Session struct {
+	File string
+
 	ImplicitHosting   bool
 	InactiveCursors   bool
 	MercifulReconnect bool
@@ -20,6 +22,11 @@ type Session struct {
 }
 
 func (Session) Init(cmd *cobra.Command) error {
+	cmd.PersistentFlags().String("session.file", "", "if sessions should be stored in a file, otherwise they will be stored only in memory")
+	if err := viper.BindPFlag("session.file", cmd.PersistentFlags().Lookup("session.file")); err != nil {
+		return err
+	}
+
 	cmd.PersistentFlags().Bool("session.implicit_hosting", true, "allow implicit control switching")
 	if err := viper.BindPFlag("session.implicit_hosting", cmd.PersistentFlags().Lookup("session.implicit_hosting")); err != nil {
 		return err
@@ -65,6 +72,8 @@ func (Session) Init(cmd *cobra.Command) error {
 }
 
 func (s *Session) Set() {
+	s.File = viper.GetString("session.file")
+
 	s.ImplicitHosting = viper.GetBool("session.implicit_hosting")
 	s.InactiveCursors = viper.GetBool("session.inactive_cursors")
 	s.MercifulReconnect = viper.GetBool("session.merciful_reconnect")

internal/session/manager.go

@@ -49,6 +49,9 @@ func New(config *config.Session) *SessionManagerCtx {
 		}
 	}
 
+	// try to load sessions from file
+	manager.load()
+
 	return manager
 }
 
@@ -102,6 +105,8 @@ func (manager *SessionManagerCtx) Create(id string, profile types.MemberProfile)
 	manager.sessionsMu.Unlock()
 
 	manager.emmiter.Emit("created", session)
+	manager.save()
+
 	return session, token, nil
 }
 
@@ -118,6 +123,8 @@ func (manager *SessionManagerCtx) Update(id string, profile types.MemberProfile)
 	manager.sessionsMu.Unlock()
 
 	manager.emmiter.Emit("profile_changed", session)
+	manager.save()
+
 	session.profileChanged()
 	return nil
 }
@@ -143,6 +150,8 @@ func (manager *SessionManagerCtx) Delete(id string) error {
 	}
 
 	manager.emmiter.Emit("deleted", session)
+	manager.save()
+
 	return nil
 }
 

internal/session/serialize.go

@@ -0,0 +1,97 @@
+package session
+
+import (
+	"encoding/json"
+	"errors"
+	"os"
+
+	"github.com/demodesk/neko/pkg/types"
+)
+
+func (manager *SessionManagerCtx) save() {
+	if manager.config.File == "" {
+		return
+	}
+
+	// serialize sessions
+	sessions := make([]types.SessionProfile, 0, len(manager.sessions))
+	for _, session := range manager.sessions {
+		sessions = append(sessions, types.SessionProfile{
+			Id:      session.id,
+			Token:   session.token,
+			Profile: session.profile,
+		})
+	}
+
+	// convert to json
+	data, err := json.Marshal(sessions)
+	if err != nil {
+		manager.logger.Error().Err(err).Msg("failed to marshal sessions")
+		return
+	}
+
+	// write to file
+	err = os.WriteFile(manager.config.File, data, 0644)
+	if err != nil {
+		manager.logger.Error().Err(err).
+			Str("file", manager.config.File).
+			Msg("failed to write sessions to a file")
+	}
+}
+
+func (manager *SessionManagerCtx) load() {
+	if manager.config.File == "" {
+		return
+	}
+
+	// read file
+	data, err := os.ReadFile(manager.config.File)
+	if err != nil {
+		// if file does not exist
+		if errors.Is(err, os.ErrNotExist) {
+			manager.logger.Info().
+				Str("file", manager.config.File).
+				Msg("sessions file does not exist")
+			return
+		}
+		manager.logger.Error().Err(err).
+			Str("file", manager.config.File).
+			Msg("failed to read sessions from a file")
+		return
+	}
+
+	// if file is empty
+	if len(data) == 0 {
+		manager.logger.Info().
+			Str("file", manager.config.File).
+			Msg("sessions file is empty")
+		return
+	}
+
+	// deserialize sessions
+	sessions := make([]types.SessionProfile, 0)
+	err = json.Unmarshal(data, &sessions)
+	if err != nil {
+		manager.logger.Error().Err(err).Msg("failed to unmarshal sessions")
+		return
+	}
+
+	// create sessions
+	manager.sessionsMu.Lock()
+	for _, session := range sessions {
+		manager.tokens[session.Token] = session.Id
+		manager.sessions[session.Id] = &SessionCtx{
+			id:      session.Id,
+			token:   session.Token,
+			manager: manager,
+			logger:  manager.logger.With().Str("session_id", session.Id).Logger(),
+			profile: session.Profile,
+		}
+	}
+	manager.sessionsMu.Unlock()
+
+	manager.logger.Info().
+		Int("sessions", len(sessions)).
+		Str("file", manager.config.File).
+		Msg("loaded sessions from a file")
+}

pkg/types/session.go

@@ -17,6 +17,12 @@ type Cursor struct {
 	Y int `json:"y"`
 }
 
+type SessionProfile struct {
+	Id      string
+	Token   string
+	Profile MemberProfile
+}
+
 type SessionState struct {
 	IsConnected bool `json:"is_connected"`
 	IsWatching  bool `json:"is_watching"`