init

internal/api/handler/chat.go

@@ -0,0 +1,157 @@
+package handler
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"net/http"
+	"qd-sc/internal/model"
+	"qd-sc/internal/service"
+	"time"
+
+	"github.com/gin-gonic/gin"
+)
+
+// 使用服务层定义的固定模型名称
+
+// ChatHandler 聊天处理器
+type ChatHandler struct {
+	chatService *service.ChatService
+	response    *Response
+}
+
+// NewChatHandler 创建聊天处理器
+func NewChatHandler(chatService *service.ChatService) *ChatHandler {
+	return &ChatHandler{
+		chatService: chatService,
+		response:    DefaultResponse,
+	}
+}
+
+// ChatCompletions 处理聊天completions请求
+func (h *ChatHandler) ChatCompletions(c *gin.Context) {
+	var req model.ChatCompletionRequest
+
+	// 只支持 JSON 请求（文件通过 image_url 字段以 URL 方式传递）
+	if err := c.ShouldBindJSON(&req); err != nil {
+		h.response.Error(c, http.StatusBadRequest, "invalid_request", "无效的请求格式: "+err.Error())
+		return
+	}
+
+	// 验证请求
+	if req.Model == "" {
+		h.response.Error(c, http.StatusBadRequest, "invalid_request", "缺少model参数")
+		return
+	}
+	// 验证模型名称（只接受固定模型名）
+	if req.Model != service.ExposedModelName {
+		h.response.Error(c, http.StatusBadRequest, "invalid_request", fmt.Sprintf("不支持的模型，请使用: %s", service.ExposedModelName))
+		return
+	}
+	if len(req.Messages) == 0 {
+		h.response.Error(c, http.StatusBadRequest, "invalid_request", "messages不能为空")
+		return
+	}
+
+	// 根据stream参数决定返回方式
+	if req.Stream {
+		h.handleStreamResponse(c, &req)
+	} else {
+		h.handleNonStreamResponse(c, &req)
+	}
+}
+
+// handleNonStreamResponse 处理非流式响应
+func (h *ChatHandler) handleNonStreamResponse(c *gin.Context, req *model.ChatCompletionRequest) {
+	resp, err := h.chatService.ProcessChatRequest(req)
+	if err != nil {
+		log.Printf("处理聊天请求失败: %v", err)
+		h.response.Error(c, http.StatusInternalServerError, "internal_error", "处理请求失败: "+err.Error())
+		return
+	}
+
+	h.response.Success(c, resp)
+}
+
+// handleStreamResponse 处理流式响应
+func (h *ChatHandler) handleStreamResponse(c *gin.Context, req *model.ChatCompletionRequest) {
+	// 设置SSE响应头
+	c.Header("Content-Type", "text/event-stream")
+	c.Header("Cache-Control", "no-cache")
+	c.Header("Connection", "keep-alive")
+	c.Header("Transfer-Encoding", "chunked")
+
+	// 传递context以支持取消
+	ctx := c.Request.Context()
+	chunkChan, errChan := h.chatService.ProcessChatRequestStream(ctx, req)
+
+	// 持续发送流式数据
+	for {
+		select {
+		case chunk, ok := <-chunkChan:
+			if !ok {
+				// 通道已关闭，发送[DONE]标记（OpenAI标准格式）
+				if _, err := fmt.Fprintf(c.Writer, "data: [DONE]\n\n"); err != nil {
+					log.Printf("写入[DONE]标记失败: %v", err)
+				}
+				c.Writer.Flush()
+				log.Printf("SSE流已结束，已发送[DONE]标记")
+				return
+			}
+
+			// 发送chunk
+			chunkJSON, err := json.Marshal(chunk)
+			if err != nil {
+				log.Printf("序列化chunk失败: %v", err)
+				continue
+			}
+
+			// 写入SSE格式
+			if _, err := fmt.Fprintf(c.Writer, "data: %s\n\n", string(chunkJSON)); err != nil {
+				log.Printf("写入SSE数据失败: %v", err)
+				return
+			}
+			c.Writer.Flush()
+
+			// 如果这个chunk包含finish_reason，记录日志
+			if len(chunk.Choices) > 0 && chunk.Choices[0].FinishReason != "" {
+				log.Printf("已发送finish_reason=%s的chunk", chunk.Choices[0].FinishReason)
+			}
+
+		case err, ok := <-errChan:
+			if ok && err != nil {
+				log.Printf("流式处理错误: %v", err)
+				// 发送错误信息
+				errChunk := model.ChatCompletionChunk{
+					ID:      fmt.Sprintf("chatcmpl-%d", time.Now().Unix()),
+					Object:  "chat.completion.chunk",
+					Created: time.Now().Unix(),
+					Model:   service.ExposedModelName,
+					Choices: []model.ChunkChoice{
+						{
+							Index: 0,
+							Delta: model.Message{
+								Role:    "assistant",
+								Content: fmt.Sprintf("\n\n错误：%s", err.Error()),
+							},
+							FinishReason: "error",
+						},
+					},
+				}
+				chunkJSON, _ := json.Marshal(errChunk)
+				fmt.Fprintf(c.Writer, "data: %s\n\n", string(chunkJSON))
+				c.Writer.Flush()
+
+				// 发送DONE
+				fmt.Fprintf(c.Writer, "data: [DONE]\n\n")
+				c.Writer.Flush()
+				return
+			}
+
+		case <-c.Request.Context().Done():
+			// 客户端断开连接
+			log.Printf("客户端断开连接")
+			return
+		}
+	}
+}