wip `/api/chat`

api/types.go

@@ -31,6 +31,22 @@ func (e StatusError) Error() string {
 	}
 }
 
+// /api/chat
+type Message struct {
+	Role    string `json:"role"`
+	Content string `json:"content"`
+}
+
+type ChatRequest struct {
+	Model    string    `json:"model"`
+	Messages []Message `json:"messages"`
+}
+
+type ChatResponse struct {
+	CreatedAt time.Time `json:"created_at"`
+	Message   Message   `json:"message"`
+}
+
 type GenerateRequest struct {
 	Model    string `json:"model"`
 	Prompt   string `json:"prompt"`

server/images.go

@@ -54,6 +54,54 @@ type Model struct {
 	Embeddings    []vector.Embedding
 }
 
+func (m *Model) ChatPrompt(messages []api.Message) (string, error) {
+	tmpl, err := template.New("").Parse(m.Template)
+	if err != nil {
+		return "", err
+	}
+
+	var vars struct {
+		System string
+		Prompt string
+		First  bool
+	}
+
+	vars.First = true
+
+	var sb strings.Builder
+	flush := func() {
+		tmpl.Execute(&sb, vars)
+		vars.System = ""
+		vars.Prompt = ""
+	}
+
+	// build the chat history from messages
+	for _, m := range messages {
+		if m.Role == "system" {
+			if vars.System != "" {
+				flush()
+			}
+			vars.System = m.Content
+		}
+
+		if m.Role == "user" {
+			if vars.Prompt != "" {
+				flush()
+			}
+			vars.Prompt = m.Content
+		}
+
+		if m.Role == "assistant" {
+			flush()
+			sb.Write([]byte(m.Content))
+		}
+	}
+
+	flush()
+
+	return sb.String(), nil
+}
+
 func (m *Model) Prompt(request api.GenerateRequest, embedding string) (string, error) {
 	t := m.Template
 	if request.Template != "" {

server/routes.go

@@ -156,6 +156,54 @@ func load(ctx context.Context, workDir string, model *Model, reqOpts map[string]
 	return nil
 }
 
+func ChatModelHandler(c *gin.Context) {
+	loaded.mu.Lock()
+	defer loaded.mu.Unlock()
+
+	var req api.ChatRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	model, err := GetModel(req.Model)
+	if err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	prompt, err := model.ChatPrompt(req.Messages)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	var response string
+	fn := func(r api.GenerateResponse) {
+		response += r.Response
+	}
+
+	workDir := c.GetString("workDir")
+	if err := load(c.Request.Context(), workDir, model, nil, defaultSessionDuration); err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+
+	fmt.Println(prompt)
+
+	if err := loaded.llm.Predict(c.Request.Context(), []int{}, prompt, fn); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+	}
+
+	c.JSON(http.StatusOK, api.ChatResponse{
+		Message: api.Message{
+			Role:    "assistant",
+			Content: response,
+		},
+		CreatedAt: time.Now().UTC(),
+	})
+}
+
 func GenerateHandler(c *gin.Context) {
 	loaded.mu.Lock()
 	defer loaded.mu.Unlock()
@@ -552,6 +600,7 @@ func Serve(ln net.Listener, allowOrigins []string) error {
 		},
 	)
 
+	r.POST("/api/chat", ChatModelHandler)
 	r.POST("/api/pull", PullModelHandler)
 	r.POST("/api/generate", GenerateHandler)
 	r.POST("/api/embeddings", EmbeddingHandler)