feat: Enhance DeepSeek API compatibility by updating SSE parsing, standardizing error responses, and improving API key management in the tester UI.

internal/adapter/openai/handler.go

@@ -42,7 +42,7 @@ func (h *Handler) ChatCompletions(w http.ResponseWriter, r *http.Request) {
 		if err == auth.ErrNoAccount {
 			status = http.StatusTooManyRequests
 		}
-		writeJSON(w, status, map[string]any{"error": detail})
+		writeOpenAIError(w, status, detail)
 		return
 	}
 	defer h.Auth.Release(a)
@@ -50,18 +50,18 @@ func (h *Handler) ChatCompletions(w http.ResponseWriter, r *http.Request) {
 
 	var req map[string]any
 	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
-		writeJSON(w, http.StatusBadRequest, map[string]any{"error": "invalid json"})
+		writeOpenAIError(w, http.StatusBadRequest, "invalid json")
 		return
 	}
 	model, _ := req["model"].(string)
 	messagesRaw, _ := req["messages"].([]any)
 	if model == "" || len(messagesRaw) == 0 {
-		writeJSON(w, http.StatusBadRequest, map[string]any{"error": "Request must include 'model' and 'messages'."})
+		writeOpenAIError(w, http.StatusBadRequest, "Request must include 'model' and 'messages'.")
 		return
 	}
 	thinkingEnabled, searchEnabled, ok := config.GetModelConfig(model)
 	if !ok {
-		writeJSON(w, http.StatusServiceUnavailable, map[string]any{"error": fmt.Sprintf("Model '%s' is not available.", model)})
+		writeOpenAIError(w, http.StatusServiceUnavailable, fmt.Sprintf("Model '%s' is not available.", model))
 		return
 	}
 
@@ -74,12 +74,16 @@ func (h *Handler) ChatCompletions(w http.ResponseWriter, r *http.Request) {
 
 	sessionID, err := h.DS.CreateSession(r.Context(), a, 3)
 	if err != nil {
-		writeJSON(w, http.StatusUnauthorized, map[string]any{"error": "invalid token."})
+		if a.UseConfigToken {
+			writeOpenAIError(w, http.StatusUnauthorized, "Account token is invalid. Please re-login the account in admin.")
+		} else {
+			writeOpenAIError(w, http.StatusUnauthorized, "Invalid token. If this should be a DS2API key, add it to config.keys first.")
+		}
 		return
 	}
 	pow, err := h.DS.GetPow(r.Context(), a, 3)
 	if err != nil {
-		writeJSON(w, http.StatusUnauthorized, map[string]any{"error": "Failed to get PoW (invalid token or unknown error)."})
+		writeOpenAIError(w, http.StatusUnauthorized, "Failed to get PoW (invalid token or unknown error).")
 		return
 	}
 	payload := map[string]any{
@@ -92,7 +96,7 @@ func (h *Handler) ChatCompletions(w http.ResponseWriter, r *http.Request) {
 	}
 	resp, err := h.DS.CallCompletion(r.Context(), a, payload, pow, 3)
 	if err != nil {
-		writeJSON(w, http.StatusInternalServerError, map[string]any{"error": "Failed to get completion."})
+		writeOpenAIError(w, http.StatusInternalServerError, "Failed to get completion.")
 		return
 	}
 	if toBool(req["stream"]) {
@@ -106,7 +110,7 @@ func (h *Handler) handleNonStream(w http.ResponseWriter, ctx context.Context, re
 	defer resp.Body.Close()
 	if resp.StatusCode != http.StatusOK {
 		body, _ := io.ReadAll(resp.Body)
-		writeJSON(w, resp.StatusCode, map[string]any{"error": string(body)})
+		writeOpenAIError(w, resp.StatusCode, string(body))
 		return
 	}
 	thinking := strings.Builder{}
@@ -183,7 +187,7 @@ func (h *Handler) handleStream(w http.ResponseWriter, r *http.Request, resp *htt
 	defer resp.Body.Close()
 	if resp.StatusCode != http.StatusOK {
 		body, _ := io.ReadAll(resp.Body)
-		writeJSON(w, resp.StatusCode, map[string]any{"error": string(body)})
+		writeOpenAIError(w, resp.StatusCode, string(body))
 		return
 	}
 	w.Header().Set("Content-Type", "text/event-stream")
@@ -191,7 +195,7 @@ func (h *Handler) handleStream(w http.ResponseWriter, r *http.Request, resp *htt
 	w.Header().Set("Connection", "keep-alive")
 	flusher, ok := w.(http.Flusher)
 	if !ok {
-		writeJSON(w, http.StatusInternalServerError, map[string]any{"error": "streaming unsupported"})
+		writeOpenAIError(w, http.StatusInternalServerError, "streaming unsupported")
 		return
 	}
 
@@ -436,3 +440,32 @@ func writeJSON(w http.ResponseWriter, status int, payload any) {
 	w.WriteHeader(status)
 	_ = json.NewEncoder(w).Encode(payload)
 }
+
+func writeOpenAIError(w http.ResponseWriter, status int, message string) {
+	writeJSON(w, status, map[string]any{
+		"error": map[string]any{
+			"message": message,
+			"type":    openAIErrorType(status),
+		},
+	})
+}
+
+func openAIErrorType(status int) string {
+	switch status {
+	case http.StatusBadRequest:
+		return "invalid_request_error"
+	case http.StatusUnauthorized:
+		return "authentication_error"
+	case http.StatusForbidden:
+		return "permission_error"
+	case http.StatusTooManyRequests:
+		return "rate_limit_error"
+	case http.StatusServiceUnavailable:
+		return "service_unavailable_error"
+	default:
+		if status >= 500 {
+			return "api_error"
+		}
+		return "invalid_request_error"
+	}
+}

internal/deepseek/transport/transport.go

@@ -3,6 +3,7 @@ package transport
 import (
 	"context"
 	"crypto/tls"
+	"fmt"
 	"net"
 	"net/http"
 	"time"
@@ -44,16 +45,36 @@ func safariTLSDialer() func(ctx context.Context, network, addr string) (net.Conn
 			return nil, err
 		}
 		host, _, _ := net.SplitHostPort(addr)
-		uCfg := &utls.Config{
-			ServerName: host,
-			NextProtos: []string{"http/1.1"},
-		}
+		uCfg := &utls.Config{ServerName: host}
 		uConn := utls.UClient(plainConn, uCfg, utls.HelloSafari_Auto)
+		if err := forceHTTP11ALPN(uConn); err != nil {
+			_ = plainConn.Close()
+			return nil, err
+		}
 		err = uConn.HandshakeContext(ctx)
 		if err != nil {
 			_ = plainConn.Close()
 			return nil, err
 		}
+		if negotiated := uConn.ConnectionState().NegotiatedProtocol; negotiated != "" && negotiated != "http/1.1" {
+			_ = uConn.Close()
+			return nil, fmt.Errorf("unexpected ALPN protocol negotiated: %s", negotiated)
+		}
 		return uConn, nil
 	}
 }
+
+func forceHTTP11ALPN(uConn *utls.UConn) error {
+	if err := uConn.BuildHandshakeState(); err != nil {
+		return err
+	}
+	for _, ext := range uConn.Extensions {
+		alpnExt, ok := ext.(*utls.ALPNExtension)
+		if !ok {
+			continue
+		}
+		alpnExt.AlpnProtocols = []string{"http/1.1"}
+		return nil
+	}
+	return nil
+}

internal/sse/parser.go

@@ -59,6 +59,42 @@ func ParseSSEChunkForContent(chunk map[string]any, thinkingEnabled bool, current
 		}
 	}
 	newType := currentFragmentType
+	parts := make([]ContentPart, 0, 8)
+
+	// Newer DeepSeek responses may emit fragment APPEND directly on
+	// path "response/fragments" instead of wrapping it in path "response".
+	if path == "response/fragments" {
+		if op, _ := chunk["o"].(string); strings.EqualFold(op, "APPEND") {
+			if frags, ok := v.([]any); ok {
+				for _, frag := range frags {
+					fm, ok := frag.(map[string]any)
+					if !ok {
+						continue
+					}
+					t, _ := fm["type"].(string)
+					content, _ := fm["content"].(string)
+					t = strings.ToUpper(t)
+					switch t {
+					case "THINK", "THINKING":
+						newType = "thinking"
+						if content != "" {
+							parts = append(parts, ContentPart{Text: content, Type: "thinking"})
+						}
+					case "RESPONSE":
+						newType = "text"
+						if content != "" {
+							parts = append(parts, ContentPart{Text: content, Type: "text"})
+						}
+					default:
+						if content != "" {
+							parts = append(parts, ContentPart{Text: content, Type: "text"})
+						}
+					}
+				}
+			}
+		}
+	}
+
 	if path == "response" {
 		if arr, ok := v.([]any); ok {
 			for _, it := range arr {
@@ -99,7 +135,6 @@ func ParseSSEChunkForContent(chunk map[string]any, thinkingEnabled bool, current
 			partType = newType
 		}
 	}
-	parts := make([]ContentPart, 0, 8)
 	switch val := v.(type) {
 	case string:
 		if val == "FINISHED" && (path == "" || path == "status") {

internal/sse/parser_test.go

@@ -47,3 +47,43 @@ func TestIsCitation(t *testing.T) {
 		t.Fatal("expected citation false")
 	}
 }
+
+func TestParseSSEChunkForContentFragmentsAppendSwitchToResponse(t *testing.T) {
+	chunk := map[string]any{
+		"p": "response/fragments",
+		"o": "APPEND",
+		"v": []any{
+			map[string]any{
+				"type":    "RESPONSE",
+				"content": "你好",
+			},
+		},
+	}
+	parts, finished, nextType := ParseSSEChunkForContent(chunk, true, "thinking")
+	if finished {
+		t.Fatal("expected unfinished")
+	}
+	if nextType != "text" {
+		t.Fatalf("expected next type text, got %q", nextType)
+	}
+	if len(parts) != 1 || parts[0].Type != "text" || parts[0].Text != "你好" {
+		t.Fatalf("unexpected parts: %#v", parts)
+	}
+}
+
+func TestParseSSEChunkForContentAfterAppendUsesUpdatedType(t *testing.T) {
+	chunk := map[string]any{
+		"p": "response/fragments/-1/content",
+		"v": "！",
+	}
+	parts, finished, nextType := ParseSSEChunkForContent(chunk, true, "text")
+	if finished {
+		t.Fatal("expected unfinished")
+	}
+	if nextType != "text" {
+		t.Fatalf("expected next type text, got %q", nextType)
+	}
+	if len(parts) != 1 || parts[0].Type != "text" || parts[0].Text != "！" {
+		t.Fatalf("unexpected parts: %#v", parts)
+	}
+}