X-Git-Url: http://git.giacomolli.uk/onechat/blobdiff_plain/c9183f90d757006e7221ecd0d4dc0db2a25f87e0..ec38dadaaf127d8bd2ffb72df450e8d3f5ac88c0:/memory.go?ds=sidebyside

diff --git a/memory.go b/memory.go
index c3e9f45..6937726 100644
--- a/memory.go
+++ b/memory.go
@@ -39,6 +39,10 @@ type Task struct {
 // start. It never builds the views again from the log, because a new view
 // differs from the live one and so loses the prompt cache.
 //
+// Each write goes to the operating system at once, and a syncer makes the
+// writes durable by group commit in the background. Flush waits until the
+// writes so far are durable.
+//
 // The summarizer builds the nodes in the queue in the background. The start
 // reads the indexes once to fill the queue again. After that, only a new
 // message or a new node adds work. Memory keeps the nodes of the views and the
@@ -48,10 +52,11 @@ type Memory struct {
 	mutex      sync.Mutex
 	root       string
 	log        *Log
+	syncer     *syncer
 	tree       *Tree
 	chat       *View
 	cview      *View
-	queue      *queue
+	queue      *BuildQueue
 	summarizer Summarizer
 	ctx        context.Context
 	cancel     context.CancelFunc
@@ -61,8 +66,8 @@ type Memory struct {
 
 // viewFile is the content of view.json.
 type viewFile struct {
-	Chat       viewState `json:"chat"`
-	Compaction viewState `json:"compaction"`
+	Chat       ViewState `json:"chat"`
+	Compaction ViewState `json:"compaction"`
 }
 
 // openMemory opens the chat in root and starts the builds that are ready. The
@@ -77,13 +82,18 @@ func openMemory(ctx context.Context, root string, clock func() time.Time, summar
 	m := &Memory{
 		root:       root,
 		log:        log,
-		queue:      newQueue(),
+		queue:      newBuildQueue(),
 		summarizer: summarizer,
 		changed:    make(chan struct{}),
 	}
 
 	m.ctx, m.cancel = context.WithCancel(ctx)
 
+	m.syncer, err = openSyncer(root)
+	if err != nil {
+		return nil, errors.Join(err, m.Close())
+	}
+
 	m.tree, err = openTree(ctx, root, log.Len(), clock)
 	if err != nil {
 		return nil, errors.Join(err, m.Close())
@@ -105,6 +115,7 @@ func openMemory(ctx context.Context, root string, clock func() time.Time, summar
 	}
 
 	m.mutex.Lock()
+	m.syncer.Written()
 	m.dispatch()
 	m.mutex.Unlock()
 
@@ -115,8 +126,8 @@ func openMemory(ctx context.Context, root string, clock func() time.Time, summar
 func (m *Memory) load() error {
 	data, err := os.ReadFile(m.viewPath())
 	if errors.Is(err, os.ErrNotExist) && m.log.Len() == 0 {
-		m.chat = newView(chatHigh, chatLow)
-		m.cview = newView(compactionHigh, compactionLow)
+		m.chat = newView(viewChatHigh, viewChatLow)
+		m.cview = newView(viewCompactionHigh, viewCompactionLow)
 
 		return nil
 	}
@@ -135,12 +146,12 @@ func (m *Memory) load() error {
 		return fmt.Errorf("decode view: %w", err)
 	}
 
-	m.chat, err = restoreView(file.Chat, chatHigh, chatLow, m.tree)
+	m.chat, err = restoreView(file.Chat, viewChatHigh, viewChatLow, m.tree)
 	if err != nil {
 		return fmt.Errorf("chat view: %w", err)
 	}
 
-	m.cview, err = restoreView(file.Compaction, compactionHigh, compactionLow, m.tree)
+	m.cview, err = restoreView(file.Compaction, viewCompactionHigh, viewCompactionLow, m.tree)
 	if err != nil {
 		return fmt.Errorf("compaction view: %w", err)
 	}
@@ -227,8 +238,8 @@ func (m *Memory) catchUp() error {
 	return m.save()
 }
 
-// Close stops the builds, waits for them, closes the files of the chat, and
-// releases its lock.
+// Close stops the builds, waits for them, makes the writes durable, closes the
+// files of the chat, and releases its lock.
 func (m *Memory) Close() error {
 	m.cancel()
 	m.workers.Wait()
@@ -237,8 +248,12 @@ func (m *Memory) Close() error {
 	defer m.mutex.Unlock()
 
 	var err error
+	if m.syncer != nil {
+		err = m.syncer.Close()
+	}
+
 	if m.tree != nil {
-		err = m.tree.Close()
+		err = errors.Join(err, m.tree.Close())
 	}
 
 	return errors.Join(err, m.log.Close())
@@ -255,6 +270,8 @@ func (m *Memory) Append(kind, text string) (Message, error) {
 		return Message{}, err
 	}
 
+	defer m.syncer.Written()
+
 	err = m.addMessage(message)
 	if err != nil {
 		return Message{}, err
@@ -457,6 +474,7 @@ func (m *Memory) run(key nodeKey, task Task) {
 			Text:  text,
 			Size:  len(text),
 		})
+		m.syncer.Written()
 	}
 
 	if err != nil {
@@ -490,6 +508,11 @@ func (m *Memory) Wait(ctx context.Context) error {
 	}
 }
 
+// Flush returns when every write before the call is durable.
+func (m *Memory) Flush(ctx context.Context) error {
+	return m.syncer.Flush(ctx)
+}
+
 // save writes the views to view.json.
 func (m *Memory) save() error {
 	data, err := json.Marshal(viewFile{
@@ -520,6 +543,39 @@ func (m *Memory) View() string {
 	return m.chat.Render()
 }
 
+// ViewLines returns the lines of the chat view, each with its newline, without
+// the leaf lines of the messages in skip.
+func (m *Memory) ViewLines(skip map[int]bool) []string {
+	m.mutex.Lock()
+	defer m.mutex.Unlock()
+
+	return m.chat.LinesWithout(skip)
+}
+
+// Len returns the number of messages in the log.
+func (m *Memory) Len() int {
+	m.mutex.Lock()
+	defer m.mutex.Unlock()
+
+	return m.log.Len()
+}
+
+// Message reads the message with the given ID.
+func (m *Memory) Message(id int) (Message, error) {
+	m.mutex.Lock()
+	defer m.mutex.Unlock()
+
+	return m.log.Message(id)
+}
+
+// Node reads the node (l, i) if it is built.
+func (m *Memory) Node(level, index int) (Node, bool, error) {
+	m.mutex.Lock()
+	defer m.mutex.Unlock()
+
+	return m.tree.Node(level, index)
+}
+
 // Context returns the compaction view for the build of node (l, i). It ends
 // before the message of a leaf, or after the last message of a merge, and it
 // stops at the first line that is not built.