WeKnora deployment source with the reviewed wiki identity, summary and recovery fixes

internal/stream/memory_manager.go

@@ -0,0 +1,118 @@
+package stream
+
+import (
+	"context"
+	"sync"
+	"time"
+
+	"github.com/Tencent/WeKnora/internal/types/interfaces"
+)
+
+// memoryStreamData holds stream events in memory
+type memoryStreamData struct {
+	events      []interfaces.StreamEvent
+	lastUpdated time.Time
+	mu          sync.RWMutex
+}
+
+// MemoryStreamManager implements StreamManager using in-memory storage
+type MemoryStreamManager struct {
+	// Map: sessionID -> messageID -> stream data
+	streams map[string]map[string]*memoryStreamData
+	mu      sync.RWMutex
+}
+
+// NewMemoryStreamManager creates a new in-memory stream manager
+func NewMemoryStreamManager() *MemoryStreamManager {
+	return &MemoryStreamManager{
+		streams: make(map[string]map[string]*memoryStreamData),
+	}
+}
+
+// getOrCreateStream gets or creates stream data
+func (m *MemoryStreamManager) getOrCreateStream(sessionID, messageID string) *memoryStreamData {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	if _, exists := m.streams[sessionID]; !exists {
+		m.streams[sessionID] = make(map[string]*memoryStreamData)
+	}
+
+	if _, exists := m.streams[sessionID][messageID]; !exists {
+		m.streams[sessionID][messageID] = &memoryStreamData{
+			events:      make([]interfaces.StreamEvent, 0),
+			lastUpdated: time.Now(),
+		}
+	}
+
+	return m.streams[sessionID][messageID]
+}
+
+// getStream gets existing stream data (returns nil if not found)
+func (m *MemoryStreamManager) getStream(sessionID, messageID string) *memoryStreamData {
+	m.mu.RLock()
+	defer m.mu.RUnlock()
+
+	if sessionMap, exists := m.streams[sessionID]; exists {
+		return sessionMap[messageID]
+	}
+	return nil
+}
+
+// AppendEvent appends a single event to the stream
+func (m *MemoryStreamManager) AppendEvent(
+	ctx context.Context,
+	sessionID, messageID string,
+	event interfaces.StreamEvent,
+) error {
+	stream := m.getOrCreateStream(sessionID, messageID)
+
+	stream.mu.Lock()
+	defer stream.mu.Unlock()
+
+	// Set timestamp if not already set
+	if event.Timestamp.IsZero() {
+		event.Timestamp = time.Now()
+	}
+
+	// Append event
+	stream.events = append(stream.events, event)
+	stream.lastUpdated = time.Now()
+
+	return nil
+}
+
+// GetEvents gets events starting from offset
+// Returns: events slice, next offset, error
+func (m *MemoryStreamManager) GetEvents(
+	ctx context.Context,
+	sessionID, messageID string,
+	fromOffset int,
+) ([]interfaces.StreamEvent, int, error) {
+	stream := m.getStream(sessionID, messageID)
+	if stream == nil {
+		// Stream doesn't exist yet
+		return []interfaces.StreamEvent{}, fromOffset, nil
+	}
+
+	stream.mu.RLock()
+	defer stream.mu.RUnlock()
+
+	// Check if offset is beyond current events
+	if fromOffset >= len(stream.events) {
+		return []interfaces.StreamEvent{}, fromOffset, nil
+	}
+
+	// Get events from offset to end
+	events := stream.events[fromOffset:]
+	nextOffset := len(stream.events)
+
+	// Return copy of events to avoid race conditions
+	eventsCopy := make([]interfaces.StreamEvent, len(events))
+	copy(eventsCopy, events)
+
+	return eventsCopy, nextOffset, nil
+}
+
+// Ensure MemoryStreamManager implements StreamManager interface
+var _ interfaces.StreamManager = (*MemoryStreamManager)(nil)