fix(openai): avoid implicit image sticky sessions

2026-04-26 17:09:41 +00:00
parent c056db740d
commit 615557ec20
3 changed files with 66 additions and 13 deletions
@@ -227,6 +227,41 @@ func TestOpenAIGatewayService_GenerateSessionHash_AttachesLegacyHashToContext(t
 	require.NotEmpty(t, openAILegacySessionHashFromContext(c.Request.Context()))
 }

+func TestOpenAIGatewayService_GenerateExplicitSessionHash_SkipsContentFallback(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+	svc := &OpenAIGatewayService{}
+	body := []byte(`{"model":"gpt-image-2","prompt":"draw a cat"}`)
+
+	t.Run("stateless image body stays unstuck", func(t *testing.T) {
+		rec := httptest.NewRecorder()
+		c, _ := gin.CreateTestContext(rec)
+		c.Request = httptest.NewRequest(http.MethodPost, "/v1/images/generations", nil)
+
+		require.Empty(t, svc.GenerateExplicitSessionHash(c, body))
+		require.Empty(t, openAILegacySessionHashFromContext(c.Request.Context()))
+	})
+
+	t.Run("prompt_cache_key is explicit", func(t *testing.T) {
+		rec := httptest.NewRecorder()
+		c, _ := gin.CreateTestContext(rec)
+		c.Request = httptest.NewRequest(http.MethodPost, "/v1/images/generations", nil)
+
+		got := svc.GenerateExplicitSessionHash(c, []byte(`{"model":"gpt-image-2","prompt_cache_key":"image-session"}`))
+		require.Equal(t, fmt.Sprintf("%016x", xxhash.Sum64String("image-session")), got)
+		require.NotEmpty(t, openAILegacySessionHashFromContext(c.Request.Context()))
+	})
+
+	t.Run("header overrides body", func(t *testing.T) {
+		rec := httptest.NewRecorder()
+		c, _ := gin.CreateTestContext(rec)
+		c.Request = httptest.NewRequest(http.MethodPost, "/v1/images/generations", nil)
+		c.Request.Header.Set("session_id", "header-session")
+
+		got := svc.GenerateExplicitSessionHash(c, []byte(`{"prompt_cache_key":"body-session"}`))
+		require.Equal(t, fmt.Sprintf("%016x", xxhash.Sum64String("header-session")), got)
+	})
+}
+
 func TestOpenAIGatewayService_GenerateSessionHashWithFallback(t *testing.T) {
 	gin.SetMode(gin.TestMode)
 	rec := httptest.NewRecorder()