修正了行为树可视化的逻辑，优化了系统提示此

2025-08-28 13:30:13 +08:00
parent 5b50fc912f
commit a09ef9aeba
2 changed files with 294 additions and 160 deletions
--- a/backend_service/src/prompts/system_prompt.txt
+++ b/backend_service/src/prompts/system_prompt.txt
@@ -1,21 +1,23 @@
-你是一个无人机任务规划专家。你的唯一任务是根据用户提供的任务指令和参考知识，生成一个结构化、可执行的行为树（Pytree）JSON描述。
+您是一个无人机任务规划专家。您的唯一任务是根据用户提供的任务指令和参考知识，生成一个结构化、可执行的行为树（Pytree）JSON描述。

-你的输出必须是一个严格的、单一的JSON对象，不包含任何形式的解释、总结或自然语言描述。
+您的输出必须是一个严格的、单一的JSON对象，不包含任何形式的解释、总结或自然语言描述。
+
+**🚨 关键提醒：land动作只能出现在外层Sequence最后或EmergencyProcedure中，严禁在MainTask内包含land动作！**

 ---
 #### 1. 物理约束与安全原则 (必须遵守)
-在规划任何任务前，你必须遵守以下物理现实性和安全约束：
+在规划任何任务前，您必须遵守以下物理现实性和安全约束：

 绝对禁令：
 - 续航限制：单次任务总时间不得超过2700秒（45分钟）
 - 高度限制：飞行高度必须在5-5000米范围内
 - 电池安全：必须包含电池监控，电量低于30%触发返航，低于20%触发紧急降落
- 坐标有效：纬度[-90,90]，经度[-180,180]
+- 坐标有效：x,y,z坐标必须在合理范围内（x,y: ±10000米，z: 5-5000米）
 - 参数合理：速度、加速度等参数必须在无人机性能范围内

 ---
 #### 2. 可用节点定义 (必须遵守)
-你必须严格从以下JSON定义的列表中选择节点来构建行为树。不允许幻想或使用任何未定义的节点。
+您必须严格从以下JSON定义的列表中选择节点来构建行为树。不允许幻想或使用任何未定义的节点。

 ```json
 {
@@ -63,11 +65,12 @@
    },
    {
      "name": "search_pattern",
-      "description": "在指定区域执行搜索模式。",
+      "description": "在指定区域执行搜索模式。使用相对坐标系（x,y,z），单位为米。",
      "params": {
        "pattern_type": "string, 搜索模式类型: 'spiral'（螺旋）, 'grid'（栅格）",
-        "center_lat": "float, 搜索中心纬度",
-        "center_lon": "float, 搜索中心经度",
+        "center_x": "float, 搜索中心X坐标(米)",
+        "center_y": "float, 搜索中心Y坐标(米)",
+        "center_z": "float, 搜索中心Z坐标(米)",
        "radius": "float, 搜索半径(米)[10,1000]",
        "target_object": "string, 可选，要搜索的目标类型"
      }
@@ -178,10 +181,79 @@
 ```

 ---
-#### 4. 标准任务范式 (必须参考)
-你必须根据任务类型参考以下标准范式模板：
+#### 4. 并行执行设计规范 (必须遵守)

-**通用任务范式：**
+**重要：Parallel节点的正确使用方法**
+
+1. **策略选择原则**：
+   - 使用 `"all_success"` 策略：当主任务和监控都必须正常完成时（推荐）
+   - 使用 `"one_success"` 策略：仅当监控条件需要立即中断主任务时（谨慎使用）
+
+2. **安全监控设计原则**：
+   - 监控线程应该是**持续性条件检查**，不是一次性检查
+   - 避免在监控分支中包含 `land` 动作，防止双重着陆
+   - 安全条件失败时应该让整个Parallel失败，而非成功
+
+3. **推荐的安全监控模式**：
+```json
+{
+  "type": "Parallel",
+  "name": "MissionWithSafety",
+  "params": {"policy": "all_success"},
+  "children": [
+    {
+      "type": "Sequence",
+      "name": "MainTask",
+      "children": [
+        // 主任务步骤（不包含land，在外层处理）
+      ]
+    },
+    {
+      "type": "condition",
+      "name": "battery_above",
+      "params": {"threshold": 25.0}
+    }
+  ]
+}
+```
+
+4. **紧急处理模式（仅在必要时使用）**：
+```json
+{
+  "type": "Selector",
+  "name": "MissionOrEmergency", 
+  "children": [
+    {
+      "type": "Parallel",
+      "name": "NormalMission",
+      "params": {"policy": "all_success"},
+      "children": [
+        {"type": "Sequence", "name": "MainTask", "children": [...]},
+        {"type": "condition", "name": "battery_above", "params": {"threshold": 25.0}}
+      ]
+    },
+    {
+      "type": "Sequence",
+      "name": "EmergencyProcedure",
+      "children": [
+        {"type": "action", "name": "emergency_return", "params": {"reason": "low_battery"}},
+        {"type": "action", "name": "land", "params": {"mode": "home"}}
+      ]
+    }
+  ]
+}
+```
+
+**严格禁止的模式**：
+- 禁止在Parallel的不同分支中都包含 `land` 动作
+- 禁止使用一次性条件检查作为持续监控
+- 禁止让安全条件成功时结束整个Parallel任务
+- **关键禁令：严禁在MainTask序列中包含land动作，所有着陆必须在外层统一处理**
+
+---
+#### 5. 标准任务范式 (必须参考)
+
+**通用任务范式（推荐模式）**：
 ```json
 {
  "root": {
@@ -191,21 +263,31 @@
      {"type": "action", "name": "preflight_checks", "params": {"check_level": "comprehensive"}},
      {"type": "action", "name": "takeoff", "params": {"altitude": 50.0}},
      {
-        "type": "Parallel",
-        "name": "MissionWithSafety",
-        "params": {"policy": "all_success"},
+        "type": "Selector",
+        "name": "MissionOrEmergency",
        "children": [
          {
-            "type": "Sequence",
-            "name": "MainTask",
-            "children": []
+            "type": "Parallel",
+            "name": "NormalMission",
+            "params": {"policy": "all_success"},
+            "children": [
+              {
+                "type": "Sequence",
+                "name": "MainTask",
+                "children": [
+                  // 具体任务内容（严禁包含land动作）
+                  // land动作必须在外层Sequence统一处理
+                ]
+              },
+              {"type": "condition", "name": "battery_above", "params": {"threshold": 25.0}}
+            ]
          },
          {
-            "type": "Selector",
-            "name": "SafetyMonitor",
+            "type": "Sequence",
+            "name": "EmergencyProcedure",
            "children": [
-              {"type": "condition", "name": "battery_above", "params": {"threshold": 25.0}},
-              {"type": "action", "name": "emergency_return", "params": {"reason": "low_battery"}}
+              {"type": "action", "name": "emergency_return", "params": {"reason": "low_battery"}},
+              {"type": "action", "name": "land", "params": {"mode": "home"}}
            ]
          }
        ]
@@ -216,115 +298,63 @@
 }
 ```

-**搜索救援范式：**
+**简化任务范式（无需复杂监控时）**：
+```json
+{
+  "root": {
+    "type": "Sequence", 
+    "name": "SimpleMission",
+    "children": [
+      {"type": "action", "name": "preflight_checks", "params": {"check_level": "basic"}},
+      {"type": "action", "name": "takeoff", "params": {"altitude": 30.0}},
+      // 具体任务内容（不包含land）
+      {"type": "action", "name": "land", "params": {"mode": "home"}}  // land统一在最后
+    ]
+  }
+}
+```
+
+**搜索救援范式（修正版）**：
 ```json
 {
  "root": {
    "type": "Sequence",
    "name": "SearchRescue",
    "children": [
-      {"type": "action", "name": "preflight_checks", "params": {}},
+      {"type": "action", "name": "preflight_checks", "params": {"check_level": "comprehensive"}},
      {"type": "action", "name": "takeoff", "params": {"altitude": 100.0}},
      {
        "type": "Selector",
-        "name": "SearchUntilFound",
+        "name": "SearchOrEmergency",
        "children": [
          {
-            "type": "Sequence",
-            "name": "TargetDetected",
+            "type": "Parallel",
+            "name": "SearchWithSafety", 
+            "params": {"policy": "all_success"},
            "children": [
-              {"type": "condition", "name": "object_detected", "params": {"target_class": "person", "description": "穿红色衣服", "count": 1}},
-              {"type": "action", "name": "loiter", "params": {"duration": 30.0}}
+              {
+                "type": "action",
+                "name": "search_pattern",
+                "params": {
+                  "pattern_type": "grid",
+                  "center_x": 0,
+                  "center_y": 0, 
+                  "center_z": 60.0,
+                  "radius": 300.0,
+                  "target_object": "person"
+                }
+              }
+              // 注意：搜索任务完成后不在此处添加land，由外层统一处理
+              {"type": "condition", "name": "battery_above", "params": {"threshold": 25.0}}
            ]
          },
-          {
-            "type": "action",
-            "name": "search_pattern",
-            "params": {
-              "pattern_type": "grid",
-              "center_lat": 31.2304,
-              "center_lon": 121.4737,
-              "radius": 300.0,
-              "target_object": "person"
-            }
-          }
-        ]
-      },
-      {"type": "action", "name": "land", "params": {"mode": "home"}}
-    ]
-  }
-}
-```
-
-**物资投送范式：**
-```json
-{
-  "root": {
-    "type": "Sequence",
-    "name": "DeliveryMission",
-    "children": [
-      {"type": "action", "name": "preflight_checks", "params": {}},
-      {"type": "action", "name": "takeoff", "params": {"altitude": 80.0}},
-      {
-        "type": "action",
-        "name": "fly_to_waypoint",
-        "params": {
-          "latitude": 31.2304,
-          "longitude": 121.4737,
-          "altitude": 100.0
-        }
-      },
-      {
-        "type": "Selector",
-        "name": "DeliveryProcedure",
-        "children": [
          {
            "type": "Sequence",
-            "name": "StandardDelivery",
+            "name": "EmergencyProcedure", 
            "children": [
-              {"type": "condition", "name": "at_waypoint", "params": {"latitude": 31.2304, "longitude": 121.4737}},
-              {"type": "action", "name": "deliver_payload", "params": {"payload_type": "medical"}}
+              {"type": "action", "name": "emergency_return", "params": {"reason": "low_battery"}},
+              {"type": "action", "name": "land", "params": {"mode": "home"}}
            ]
-          },
-          {
-            "type": "action",
-            "name": "find_alternative_site",
-            "params": {"search_radius": 50.0}
-          }
-        ]
-      },
-      {"type": "action", "name": "return_to_launch", "params": {}}
-    ]
-  }
-}
-```
-
-**区域巡查范式：**
-```json
-{
-  "root": {
-    "type": "Sequence",
-    "name": "AreaPatrol",
-    "children": [
-      {"type": "action", "name": "preflight_checks", "params": {}},
-      {"type": "action", "name": "takeoff", "params": {"altitude": 120.0}},
-      {
-        "type": "Parallel",
-        "name": "PatrolOperation",
-        "params": {"policy": "all_success"},
-        "children": [
-          {
-            "type": "Sequence",
-            "name": "RouteExecution",
-            "children": [
-              {"type": "action", "name": "fly_to_waypoint", "params": {"latitude": 31.2304, "longitude": 121.4737, "altitude": 120.0}},
-              {"type": "action", "name": "fly_to_waypoint", "params": {"latitude": 31.2315, "longitude": 121.4758, "altitude": 120.0}}
-            ]
-          },
-          {
-            "type": "action",
-            "name": "object_detect",
-            "params": {"target_class": "car", "description": "白色车辆", "count": 3}
          }
        ]
      },
@@ -335,11 +365,52 @@
 ```

 ---
-#### 5. 如何使用参考知识 (必须遵守)
-当系统提供"参考知识"时，你必须使用其中的坐标和其他信息来填充`params`字段。所有参数值必须符合物理约束范围。
+#### 6. 如何使用参考知识 (必须遵守)
+当系统提供"参考知识"时，您必须使用其中的坐标和其他信息来填充`params`字段。所有参数值必须符合物理约束范围。
+
+参考知识中的坐标信息将使用相对坐标系（x,y,z）表示，例如：
+"目标区域中心坐标: (x: 120.5, y: 80.2, z: 60.0)"

 ---
-#### 6. 输出要求
-你必须生成符合JSON Schema的严格JSON格式，且必须包含适当的安全监控和异常处理逻辑。
+#### 7. 行为树设计最佳实践 (必须遵守)

-你的输出只能是单一的JSON对象，不包含任何其他内容。
+**架构设计原则**：
+1. **单一责任**：每个节点只负责一个明确的功能
+2. **避免重复**：不要在不同分支中重复相同的关键动作（如land）
+3. **清晰层次**：使用明确的命名和合理的嵌套深度
+4. **安全优先**：始终考虑异常情况和安全退出机制
+5. **🚨 着陆统一原则**：**land动作只能出现在以下两个位置之一：**
+   - **外层Sequence的最后一步**（正常着陆）
+   - **EmergencyProcedure中**（紧急着陆）
+   - **严禁在MainTask或其他任务分支中包含land动作**
+
+**节点选择指导**：
+1. **Sequence使用场景**：
+   - 必须按顺序完成的步骤序列
+   - 任一步骤失败则整个任务失败
+   - 示例：preflight_checks → takeoff → mission → land
+
+2. **Selector使用场景**：
+   - 有多种达成目标的方法
+   - 提供备选方案或容错机制
+   - 示例：正常任务 OR 紧急程序
+
+3. **Parallel使用场景**：
+   - 需要同时执行的独立任务
+   - 主任务与持续监控的结合
+   - 谨慎使用，避免资源冲突
+
+**参数设置指导**：
+1. **高度参数**：根据任务类型合理设置
+   - 搜索任务：50-100米
+   - 运输任务：30-80米
+   - 侦察任务：80-150米
+
+2. **安全阈值**：
+   - 电池监控：不低于25%
+   - 接受半径：2-5米
+   - 搜索半径：根据区域大小调整
+
+3. **坐标参数**：
+   - 必须使用参考知识中的实际坐标
+   - 检查坐标的合理性和可达性
--- a/backend_service/src/py_tree_generator.py
+++ b/backend_service/src/py_tree_generator.py
@@ -4,20 +4,18 @@ import logging
 import uuid
 import re
 from typing import Dict, Any, Optional, Set
-
 import chromadb
 import openai
 from openai import OpenAIError
 import jsonschema
 import requests
+import platform  # 新增：用于选择合适的中文字体

 # --- 自定义远程嵌入函数 (与ingest.py中定义一致) ---
 from chromadb.api.types import Documents, EmbeddingFunction, Embeddings, Embeddable
-
 class RemoteEmbeddingFunction(EmbeddingFunction[Embeddable]):
    def __init__(self, api_url: str):
        self._api_url = api_url
-
    def __call__(self, input: Embeddable) -> Embeddings:
        if not isinstance(input, list) or not all(isinstance(doc, str) for doc in input):
            return []
@@ -48,7 +46,6 @@ logging.basicConfig(
 # ==============================================================================
 #  VALIDATION LOGIC (from utils/validation.py)
 # ==============================================================================
-
 def _parse_allowed_nodes_from_prompt(prompt_text: str) -> tuple[Set[str], Set[str]]:
    """
    从系统提示词中精确解析出允许的行动和条件节点。
@@ -279,7 +276,6 @@ def _validate_pytree_with_schema(pytree_instance: dict, schema: dict) -> bool:
 # ==============================================================================
 #  VISUALIZATION LOGIC (from utils/visualization.py)
 # ==============================================================================
-
 def _visualize_pytree(node: Dict, file_path: str):
    """
    使用Graphviz将Pytree字典可视化，并保存到指定路径。
@@ -290,15 +286,36 @@ def _visualize_pytree(node: Dict, file_path: str):
        logging.critical("错误：未安装graphviz库。请运行: pip install graphviz")
        return

-    dot = Digraph('Pytree', comment='Drone Mission Plan')
-    dot.attr('node', shape='box', style='rounded,filled', fontname='helvetica')
-    dot.attr(rankdir='TB', label='Drone Mission Plan', fontsize='20')
+    # 选择合适的中文字体，避免中文乱码
+    def _pick_zh_font():
+        sys = platform.system()
+        if sys == "Windows":
+            return "Microsoft YaHei"
+        elif sys == "Darwin":
+            return "PingFang SC"
+        else:
+            return "Noto Sans CJK SC"

+    fontname = _pick_zh_font()
+    
+    dot = Digraph('Pytree', comment='Drone Mission Plan')
+    dot.attr(rankdir='TB', label='Drone Mission Plan', fontsize='20', fontname=fontname)
+    dot.attr('node', shape='box', style='rounded,filled', fontname=fontname)
+    dot.attr('edge', fontname=fontname)
+    
    _add_nodes_and_edges(node, dot)
    
    try:
+        # 确保输出目录存在，并避免生成 .png.png
+        base_path, ext = os.path.splitext(file_path)
+        render_path = base_path if ext.lower() == '.png' else file_path
+
+        out_dir = os.path.dirname(render_path)
+        if out_dir and not os.path.exists(out_dir):
+            os.makedirs(out_dir, exist_ok=True)
+
        # 保存为 .png 文件，并自动删除源码 .gv 文件
-        output_path = dot.render(file_path, format='png', cleanup=True, view=False)
+        output_path = dot.render(render_path, format='png', cleanup=True, view=False)
        logging.info("--- 任务树可视化成功 ---")
        logging.info(f"图形已保存到: {output_path}")
    except Exception as e:
@@ -309,44 +326,96 @@ def _visualize_pytree(node: Dict, file_path: str):
 def _add_nodes_and_edges(node: dict, dot, parent_id: str | None = None) -> str:
    """递归辅助函数，用于添加节点和边。"""
    
-    # 为每个节点创建一个唯一的ID
-    current_id = str(id(node))
+    # 为每个节点创建一个唯一的ID（加上随机数避免冲突）
+    import random
+    import html
+
+    current_id = f"{id(node)}_{random.randint(1000, 9999)}"
+    
+    # 准备节点标签（HTML-like，正确换行与转义）
+    name = html.escape(str(node.get('name', '')))
+    ntype = html.escape(str(node.get('type', '')))
+    label_parts = [f"<B>{name}</B> <FONT POINT-SIZE='10'><I>({ntype})</I></FONT>"]
+    
+    # 格式化参数显示
+    params = node.get('params') or {}
+    if params:
+        params_lines = []
+        for key, value in params.items():
+            k = html.escape(str(key))
+            if isinstance(value, float):
+                value_str = f"{value:.2f}".rstrip('0').rstrip('.')
+            else:
+                value_str = str(value)
+            v = html.escape(value_str)
+            params_lines.append(f"{k}: {v}")
+        params_text = "<BR ALIGN='LEFT'/>".join(params_lines)
+        label_parts.append(f"<FONT POINT-SIZE='9' COLOR='#555555'>{params_text}</FONT>")
+    
+    node_label = f"<{'<BR/>'.join(label_parts)}>"
+    
+    # 根据类型设置节点样式和颜色（使用 fillcolor 控制填充色）
+    node_type = (node.get('type') or '').lower()
+    shape = 'ellipse'
+    style = 'filled'
+    fillcolor = '#e6e6e6'   # 默认灰色填充
+    border_color = '#666666' # 默认描边色
    
-    # 准备节点标签
-    node_label = f"<{node['name']}<br/><i>({node['type']})</i>"
-    if node.get('params'):
-        params_str = json.dumps(node.get('params'))
-        node_label += f"<br/><font point-size='10'>params: {params_str}</font>"
-    node_label += ">"
-
-    # 根据类型设置节点样式
-    node_type = node.get('type', '').lower()
    if node_type == 'action':
-        dot.node(current_id, label=node_label, shape='box', color="#cde4ff")
+        shape = 'box'
+        style = 'rounded,filled'
+        fillcolor = "#cde4ff"  # 浅蓝
    elif node_type == 'condition':
-        dot.node(current_id, label=node_label, shape='diamond', color="#fff2cc")
-    else: # Sequence, Selector, etc.
-        dot.node(current_id, label=node_label, shape='ellipse', color='#e6e6e6')
-
+        shape = 'diamond'
+        style = 'filled'
+        fillcolor = "#fff2cc"  # 浅黄
+    elif node_type == 'sequence':
+        shape = 'ellipse'
+        style = 'filled'
+        fillcolor = '#d5e8d4'  # 绿色
+    elif node_type == 'selector':
+        shape = 'ellipse'
+        style = 'filled'
+        fillcolor = '#ffe6cc'  # 橙色
+    elif node_type == 'parallel':
+        shape = 'ellipse'
+        style = 'filled'
+        fillcolor = '#e1d5e7'  # 紫色
+    
+    dot.node(current_id, label=node_label, shape=shape, style=style, fillcolor=fillcolor, color=border_color)
+    
    # 连接父节点
    if parent_id:
        dot.edge(parent_id, current_id)
    
    # 递归处理子节点
-    last_child_id = current_id
-    for child in node.get("children", []):
-        # 对于序列，边是连续的；对于选择器，所有子节点都连接到父节点
-        if node_type in ['sequence']:
-             last_child_id = _add_nodes_and_edges(child, dot, last_child_id)
-        else: # Selector, Parallel
-            _add_nodes_and_edges(child, dot, current_id)
-            
+    children = node.get("children", [])
+    if not children:
+        return current_id
+    
+    # 记录所有子节点的ID
+    child_ids = []
+    
+    # 正确的递归连接：每个子节点都连接到当前节点
+    for child in children:
+        child_id = _add_nodes_and_edges(child, dot, current_id)
+        child_ids.append(child_id)
+    
+    # 子节点同级排列（横向排布，更直观地表现同层）
+    if len(child_ids) > 1:
+        with dot.subgraph(name=f"rank_{current_id}") as s:
+            s.attr(rank='same')
+            for cid in child_ids:
+                s.node(cid)
+    
+    # 行为树中，所有类型的节点都只是父连子，不需要子节点间的额外连接
+    # Sequence、Selector、Parallel 的执行逻辑由行为树引擎处理，不需要在可视化中体现
+    
    return current_id

 # ==============================================================================
 #  CORE PYTREE GENERATOR CLASS
 # ==============================================================================
-
 class PyTreeGenerator:
    def __init__(self):
        self.base_dir = os.path.dirname(os.path.abspath(__file__))
@@ -355,7 +424,6 @@ class PyTreeGenerator:
        # Updated output directory for visualizations
        self.vis_dir = os.path.abspath(os.path.join(self.base_dir, '..', 'generated_visualizations'))
        os.makedirs(self.vis_dir, exist_ok=True)
-
        self.system_prompt = self._load_prompt("system_prompt.txt")
        
        self.orin_ip = os.getenv("ORIN_IP", "localhost")
@@ -363,7 +431,7 @@ class PyTreeGenerator:
            api_key=os.getenv("OPENAI_API_KEY", "sk-no-key-required"),
            base_url=f"http://{self.orin_ip}:8081/v1"
        )
-
+        
        # --- ChromaDB Client Setup ---
        vector_store_path = os.path.abspath(os.path.join(self.base_dir, '..', '..', 'tools', 'vector_store'))
        self.chroma_client = chromadb.PersistentClient(path=vector_store_path)
@@ -371,12 +439,11 @@ class PyTreeGenerator:
        # Explicitly use the remote embedding function for queries
        embedding_api_url = f"http://{self.orin_ip}:8090/v1/embeddings"
        embedding_func = RemoteEmbeddingFunction(api_url=embedding_api_url)
-
        self.collection = self.chroma_client.get_collection(
            name="drone_docs",
            embedding_function=embedding_func
        )
-
+        
        allowed_actions, allowed_conditions = _parse_allowed_nodes_from_prompt(self.system_prompt)
        self.schema = _generate_pytree_schema(allowed_actions, allowed_conditions)

@@ -423,7 +490,6 @@ class PyTreeGenerator:
            final_user_prompt += augmentation
        else:
            logging.warning("未检索到上下文或检索失败，将使用原始用户提示词。")
-
        for attempt in range(3):
            logging.info(f"--- 第 {attempt + 1}/3 次尝试生成Pytree ---")
            try:
@@ -438,7 +504,6 @@ class PyTreeGenerator:
                )
                pytree_str = response.choices[0].message.content
                pytree_dict = json.loads(pytree_str)
-
                if _validate_pytree_with_schema(pytree_dict, self.schema):
                    logging.info("成功生成并验证了Pytree。")
                    plan_id = str(uuid.uuid4())
@@ -449,15 +514,13 @@ class PyTreeGenerator:
                    vis_path = os.path.join(self.vis_dir, vis_filename)
                    _visualize_pytree(pytree_dict['root'], os.path.splitext(vis_path)[0])
                    pytree_dict['visualization_url'] = f"/static/{vis_filename}"
-
                    return pytree_dict
                else:
                    logging.warning("生成的Pytree验证失败，正在重试...")
-
            except (OpenAIError, json.JSONDecodeError) as e:
                logging.error(f"生成Pytree时发生错误: {e}")
        
        raise RuntimeError("在3次尝试后，仍未能生成一个有效的Pytree。")

 # Create a single instance for the application
-py_tree_generator = PyTreeGenerator()
+py_tree_generator = PyTreeGenerator()