发布 0.3.0：恢复 Chat 接口并增强云端事件通知

internal/api/aigateway.go

@@ -281,7 +281,7 @@ func (h *aiGatewayHandler) streamAnthropic(c *gin.Context, body []byte, req aiwi
 	defer upstream.Close()
 	sseHeaders(c)
 	bridge := service.NewAnthRespBridge(aiRandID("msg_"), req.Model)
-	if err := forwardAnthSSE(c, upstream, bridge); err != nil {
+	if err := forwardSSEData(upstream, func(data []byte) { writeAnthEvents(c, bridge.Feed(data)) }); err != nil {
 		entry.ErrMsg = err.Error()
 	}
 	writeAnthEvents(c, bridge.Finish())
@@ -295,15 +295,16 @@ func (h *aiGatewayHandler) streamAnthropic(c *gin.Context, body []byte, req aiwi
 	h.maybeLogContent(c, callID, "anthropic", req.Model, true, req, nil)
 }
 
-// forwardAnthSSE 逐行读上游 SSE,把 data 行喂给桥并即时写出转换后的事件。
-func forwardAnthSSE(c *gin.Context, upstream io.Reader, bridge *service.AnthRespBridge) error {
+// forwardSSEData 逐行读上游 SSE,把 data 行交给 emit 即时转换写出;
+// Anthropic 与 Chat Completions 两条流式桥共用。
+func forwardSSEData(upstream io.Reader, emit func([]byte)) error {
 	reader := bufio.NewReader(upstream)
 	for {
 		line, err := reader.ReadBytes('\n')
 		if len(line) > 0 {
 			trimmed := bytes.TrimSpace(line)
 			if data, ok := bytes.CutPrefix(trimmed, []byte("data: ")); ok {
-				writeAnthEvents(c, bridge.Feed(data))
+				emit(data)
 			}
 		}
 		if err != nil {
@@ -328,6 +329,109 @@ func writeAnthEvents(c *gin.Context, events []service.AnthEvent) {
 	c.Writer.Flush()
 }
 
+// chatCompletions 是 OpenAI /ai/v1/chat/completions 端点(Tier 2 兼容层,
+// 承接只会说 Chat Completions 的存量客户端)。
+//
+// @Summary  OpenAI Chat Completions 兼容端点
+// @Tags     AI 网关
+// @Param    body body object true "OpenAI chat/completions 请求体(支持 stream;经 Responses 转换直通)"
+// @Success  200 {object} map[string]any "OpenAI 兼容响应(流式为 SSE,末尾 data: [DONE])"
+// @Router   /ai/v1/chat/completions [post]
+func (h *aiGatewayHandler) chatCompletions(c *gin.Context) {
+	var req aiwire.ChatRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		aiError(c, http.StatusBadRequest, "invalid_request_error", err.Error())
+		return
+	}
+	if strings.TrimSpace(req.Model) == "" || len(req.Messages) == 0 {
+		aiError(c, http.StatusBadRequest, "invalid_request_error", "model 与 messages 不能为空")
+		return
+	}
+	if !checkKeyModel(c, req.Model) {
+		return
+	}
+	body, err := service.ChatToResponsesBody(req)
+	if err != nil {
+		aiError(c, http.StatusBadRequest, "invalid_request_error", err.Error())
+		return
+	}
+	if req.Stream {
+		h.streamChat(c, body, req)
+		return
+	}
+	h.chatOnce(c, body, req)
+}
+
+// chatOnce 处理非流式:直通上游 → 转回 chat.completion → 记账。
+func (h *aiGatewayHandler) chatOnce(c *gin.Context, body []byte, req aiwire.ChatRequest) {
+	start := time.Now()
+	payload, meta, err := h.gw.RespPassthrough(c.Request.Context(), body, req.Model, keyGroup(c))
+	entry := h.logEntry(c, "openai", req.Model, false, meta, start)
+	if err != nil {
+		upstreamError(c, err)
+		entry.ErrMsg = err.Error()
+		h.logFailure(c, entry, req)
+		return
+	}
+	out, err := service.ResponsesToChat(payload, aiRandID("chatcmpl-"), time.Now().Unix())
+	if err != nil {
+		aiError(c, http.StatusBadGateway, "api_error", err.Error())
+		entry.ErrMsg = err.Error()
+		h.logFailure(c, entry, req)
+		return
+	}
+	entry.Status = http.StatusOK
+	fillUsage(&entry, out.Usage)
+	callID := h.gw.LogCall(entry)
+	h.maybeLogContent(c, callID, "openai", req.Model, false, req, out)
+	c.JSON(http.StatusOK, out)
+}
+
+// streamChat 流式直通并桥接:上游 Responses SSE 经 ChatRespBridge 转为
+// chat.completion.chunk 序列逐块写出,末尾发 [DONE];usage 从 completed 事件记账。
+func (h *aiGatewayHandler) streamChat(c *gin.Context, body []byte, req aiwire.ChatRequest) {
+	start := time.Now()
+	upstream, meta, err := h.gw.RespPassthroughStream(c.Request.Context(), body, req.Model, keyGroup(c))
+	entry := h.logEntry(c, "openai", req.Model, true, meta, start)
+	if err != nil {
+		upstreamError(c, err)
+		entry.ErrMsg = err.Error()
+		h.logFailure(c, entry, req)
+		return
+	}
+	defer upstream.Close()
+	sseHeaders(c)
+	includeUsage := req.StreamOptions != nil && req.StreamOptions.IncludeUsage
+	bridge := service.NewChatRespBridge(aiRandID("chatcmpl-"), req.Model, time.Now().Unix(), includeUsage)
+	if err := forwardSSEData(upstream, func(data []byte) { writeChatChunks(c, bridge.Feed(data)) }); err != nil {
+		entry.ErrMsg = err.Error()
+	}
+	writeChatChunks(c, bridge.Finish())
+	c.Writer.WriteString("data: [DONE]\n\n")
+	c.Writer.Flush()
+	entry.Status = http.StatusOK
+	entry.LatencyMs = time.Since(start).Milliseconds()
+	fillUsage(&entry, bridge.Usage())
+	callID := h.gw.LogCall(entry)
+	h.maybeLogContent(c, callID, "openai", req.Model, true, req, nil)
+}
+
+// writeChatChunks 逐块写出 chunk 的 SSE data 行并 flush。
+func writeChatChunks(c *gin.Context, chunks []aiwire.ChatChunk) {
+	for _, ch := range chunks {
+		b, err := json.Marshal(ch)
+		if err != nil {
+			continue
+		}
+		c.Writer.WriteString("data: ")
+		c.Writer.Write(b)
+		c.Writer.WriteString("\n\n")
+	}
+	if len(chunks) > 0 {
+		c.Writer.Flush()
+	}
+}
+
 // listModels 是 /ai/v1/models 端点(OpenAI 格式,从启用渠道的模型缓存聚合)。
 //
 // @Summary  可用模型列表