feat: implement high-performance JSONL session persistence with incremental append support

pkg/session/manager.go

@@ -1,9 +1,11 @@
 package session
 
 import (
+	"bufio"
 	"encoding/json"
 	"os"
 	"path/filepath"
+	"strings"
 	"sync"
 	"time"
 
@@ -68,16 +70,43 @@ func (sm *SessionManager) GetOrCreate(key string) *Session {
 }
 
 func (sm *SessionManager) AddMessage(sessionKey, role, content string) {
-	session := sm.GetOrCreate(sessionKey)
-
-	session.mu.Lock()
-	defer session.mu.Unlock()
-
-	session.Messages = append(session.Messages, providers.Message{
+	sm.AddMessageFull(sessionKey, providers.Message{
 		Role:    role,
 		Content: content,
 	})
+}
+
+func (sm *SessionManager) AddMessageFull(sessionKey string, msg providers.Message) {
+	session := sm.GetOrCreate(sessionKey)
+
+	session.mu.Lock()
+	session.Messages = append(session.Messages, msg)
 	session.Updated = time.Now()
+	session.mu.Unlock()
+
+	// 立即持久化 (Append-only)
+	sm.appendMessage(sessionKey, msg)
+}
+
+func (sm *SessionManager) appendMessage(sessionKey string, msg providers.Message) error {
+	if sm.storage == "" {
+		return nil
+	}
+
+	sessionPath := filepath.Join(sm.storage, sessionKey+".jsonl")
+	f, err := os.OpenFile(sessionPath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	data, err := json.Marshal(msg)
+	if err != nil {
+		return err
+	}
+
+	_, err = f.Write(append(data, '\n'))
+	return err
 }
 
 func (sm *SessionManager) GetHistory(key string) []providers.Message {
@@ -147,21 +176,20 @@ func (sm *SessionManager) TruncateHistory(key string, keepLast int) {
 }
 
 func (sm *SessionManager) Save(session *Session) error {
+	// 现已通过 AddMessageFull 实时增量持久化
+	// 这里保留 Save 方法用于更新 Summary 等元数据
 	if sm.storage == "" {
 		return nil
 	}
 
-	session.mu.RLock()
-	defer session.mu.RUnlock()
-
-	sessionPath := filepath.Join(sm.storage, session.Key+".json")
-
-	data, err := json.MarshalIndent(session, "", "  ")
-	if err != nil {
-		return err
+	metaPath := filepath.Join(sm.storage, session.Key+".meta")
+	meta := map[string]interface{}{
+		"summary": session.Summary,
+		"updated": session.Updated,
+		"created": session.Created,
 	}
-
-	return os.WriteFile(sessionPath, data, 0644)
+	data, _ := json.MarshalIndent(meta, "", "  ")
+	return os.WriteFile(metaPath, data, 0644)
 }
 
 func (sm *SessionManager) loadSessions() error {
@@ -175,22 +203,47 @@ func (sm *SessionManager) loadSessions() error {
 			continue
 		}
 
-		if filepath.Ext(file.Name()) != ".json" {
-			continue
+		// 处理 JSONL 历史消息
+		if filepath.Ext(file.Name()) == ".jsonl" {
+			sessionKey := strings.TrimSuffix(file.Name(), ".jsonl")
+			session := sm.GetOrCreate(sessionKey)
+
+			f, err := os.Open(filepath.Join(sm.storage, file.Name()))
+			if err != nil {
+				continue
+			}
+			
+			scanner := bufio.NewScanner(f)
+			session.mu.Lock()
+			for scanner.Scan() {
+				var msg providers.Message
+				if err := json.Unmarshal(scanner.Bytes(), &msg); err == nil {
+					session.Messages = append(session.Messages, msg)
+				}
+			}
+			session.mu.Unlock()
+			f.Close()
 		}
 
-		sessionPath := filepath.Join(sm.storage, file.Name())
-		data, err := os.ReadFile(sessionPath)
-		if err != nil {
-			continue
-		}
+		// 处理元数据
+		if filepath.Ext(file.Name()) == ".meta" {
+			sessionKey := strings.TrimSuffix(file.Name(), ".meta")
+			session := sm.GetOrCreate(sessionKey)
 
-		var session Session
-		if err := json.Unmarshal(data, &session); err != nil {
-			continue
+			data, err := os.ReadFile(filepath.Join(sm.storage, file.Name()))
+			if err == nil {
+				var meta struct {
+					Summary string    `json:"summary"`
+					Updated time.Time `json:"updated"`
+					Created time.Time `json:"created"`
+				}
+				if err := json.Unmarshal(data, &meta); err == nil {
+					session.Summary = meta.Summary
+					session.Updated = meta.Updated
+					session.Created = meta.Created
+				}
+			}
 		}
-
-		sm.sessions[session.Key] = &session
 	}
 
 	return nil