Initial commit: Pixel AI comic/video creation platform

- FastAPI backend with SQLModel, Alembic migrations, AgentScope agents
- Next.js 15 frontend with React 19, Tailwind, Zustand, React Flow
- Multi-provider AI system (DashScope, Kling, MiniMax, Volcengine, OpenAI, etc.)
- All HTTP clients migrated from sync requests to async httpx
- Admin-managed API keys via environment variables
- SSRF vulnerability fixed in ensure_url()

backend/tests/test_image_generation_api.py

@@ -0,0 +1,79 @@
+"""
+集成测试 - 图片生成 API (Task 5.4)
+
+测试图片生成 API 端点的集成测试:
+1. 测试使用复合 ID 生成图片成功
+2. 测试无效格式返回 400
+3. 测试模型不存在返回 404
+"""
+import pytest
+import sys
+import os
+
+# 添加项目根目录到路径
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), '..'))
+
+from fastapi.testclient import TestClient
+from src.main import app
+
+client = TestClient(app)
+
+
+class TestImageGenerationAPI:
+    """图片生成 API 集成测试"""
+    
+    def test_generate_image_with_valid_composite_id(self):
+        """测试使用有效的复合 ID 生成图片成功"""
+        response = client.post("/api/v1/generations/image", json={
+            "prompt": "a beautiful cat sitting on a windowsill",
+            "model": "dashscope/qwen-image",
+            "aspectRatio": "1:1",
+            "n": 1
+        })
+        
+        # 应该返回 200 或 202（任务已创建）
+        assert response.status_code in [200, 202], f"Expected 200 or 202, got {response.status_code}: {response.text}"
+        
+        data = response.json()
+        assert "data" in data, f"Response missing 'data' field: {data}"
+        assert "task_id" in data["data"], f"Response data missing 'task_id': {data}"
+        
+        # 验证 task_id 不为空
+        task_id = data["data"]["task_id"]
+        assert task_id, "task_id should not be empty"
+        assert isinstance(task_id, str), "task_id should be a string"
+    
+    def test_generate_image_invalid_format_no_separator(self):
+        """测试无效的 model 格式（缺少分隔符）返回 400"""
+        response = client.post("/api/v1/generations/image", json={
+            "prompt": "a cat",
+            "model": "qwen-image"  # ❌ 缺少 provider
+        })
+        
+        # 应该返回 400 或 422（验证错误）
+        assert response.status_code in [400, 422], f"Expected 400 or 422, got {response.status_code}: {response.text}"
+        
+        data = response.json()
+        # 错误消息应该提示正确的格式
+        error_text = str(data).lower()
+        assert "provider/model_key" in error_text or "format" in error_text, \
+            f"Error message should mention correct format: {data}"
+    
+    def test_generate_image_model_not_found(self):
+        """测试模型不存在返回 404"""
+        response = client.post("/api/v1/generations/image", json={
+            "prompt": "a cat",
+            "model": "invalid/nonexistent-model"  # 不存在的模型
+        })
+        
+        # 应该返回 404
+        assert response.status_code == 404, f"Expected 404, got {response.status_code}: {response.text}"
+        
+        data = response.json()
+        # 错误消息应该提示模型未找到
+        error_text = str(data).lower()
+        assert "not found" in error_text, f"Error message should mention 'not found': {data}"
+
+
+if __name__ == "__main__":
+    pytest.main([__file__, "-v", "--tb=short"])