fix(P2-6): use NamedTemporaryFile for automatic temp file cleanup

apps/worker/video_processing/processor.py

@@ -1,5 +1,5 @@
 """
-视频处理核心类
+视频处理器模块
 """
 
 import os
@@ -13,7 +13,7 @@ import ffmpeg
 
 @dataclass
 class VideoResult:
-    """视频生成结果"""
+    """视频结果"""
 
     output_path: str
     thumbnail_path: str
@@ -29,10 +29,10 @@ class VideoProcessor:
 
     def __init__(self, temp_dir: str = None):
         """
-        初始化视频处理器
+        初始化处理器
 
         Args:
-            temp_dir: 临时文件目录，默认使用系统临时目录
+            temp_dir: 临时目录路径，默认为系统临时目录
         """
         self.temp_dir = temp_dir or tempfile.gettempdir()
 
@@ -44,35 +44,41 @@ class VideoProcessor:
         fps: int = 25,
     ) -> VideoResult:
         """
-        拼接多个视频
+        合并多个视频
 
         Args:
             input_paths: 输入视频路径列表
             output_path: 输出视频路径
-            resolution: 输出分辨率 (width, height)
-            fps: 输出帧率
+            resolution: 分辨率 (width, height)
+            fps: 帧率
 
         Returns:
-            VideoResult: 生成结果
+            VideoResult: 视频结果
         """
         if not input_paths:
             raise ValueError("input_paths cannot be empty")
 
-        # 确保输出目录存在
+        # 创建输出目录
         os.makedirs(os.path.dirname(output_path), exist_ok=True)
 
         try:
-            # 创建临时文件列表
-            concat_file = os.path.join(self.temp_dir, f"concat_{os.getpid()}.txt")
-            with open(concat_file, "w") as f:
+            # P2-6: Use NamedTemporaryFile for automatic cleanup
+            concat_file_fd = tempfile.NamedTemporaryFile(
+                mode='w', 
+                suffix='.txt', 
+                delete=True,
+                dir=self.temp_dir
+            )
+            with concat_file_fd as concat_file:
                 for path in input_paths:
-                    # FFmpeg concat demuxer 格式
-                    f.write(f"file '{os.path.abspath(path)}'\n")
+                    # FFmpeg concat demuxer 要求绝对路径
+                    concat_file.write(f"file '{os.path.abspath(path)}'\n")
+                # Flush is automatic with context manager
 
-            # 使用 FFmpeg 拼接视频
+            # 使用 FFmpeg 合并
             width, height = resolution
             (
-                ffmpeg.input(concat_file, format="concat", safe=0)
+                ffmpeg.input(concat_file.name, format="concat", safe=0)
                 .output(
                     output_path,
                     vcodec="libx264",
@@ -86,19 +92,16 @@ class VideoProcessor:
                 .run(capture_stdout=True, capture_stderr=True)
             )
 
-            # 清理临时文件
-            os.remove(concat_file)
-
-            # 获取视频元数据
+            # 获取视频信息
             probe = ffmpeg.probe(output_path)
-            video_info = next(s for s in probe["streams"] if s["codec_type"] == "video")
+            video_stream = next(s for s in probe["streams"] if s["codec_type"] == "video")
 
             duration = float(probe["format"]["duration"])
-            width = int(video_info["width"])
-            height = int(video_info["height"])
+            width = int(video_stream["width"])
+            height = int(video_stream["height"])
 
-            # 计算帧率
-            fps_str = video_info.get("r_frame_rate", "25/1")
+            # 生成帧率
+            fps_str = video_stream.get("r_frame_rate", "25/1")
             fps_parts = fps_str.split("/")
             fps_value = float(fps_parts[0]) / float(fps_parts[1]) if len(fps_parts) == 2 else float(fps_parts[0])
 
@@ -131,15 +134,15 @@ class VideoProcessor:
         生成视频缩略图
 
         Args:
-            video_path: 视频文件路径
-            timestamp: 截图时间点（秒）
-            output_path: 输出路径，默认为视频路径 + .jpg
+            video_path: 视频路径
+            timestamp: 截图时间点
+            output_path: 输出路径，默认在视频同目录下生成 thumbnail.jpg
 
         Returns:
             缩略图路径
         """
         if output_path is None:
-            output_path = f"{os.path.splitext(video_path)[0]}_thumb.jpg"
+            output_path = f"{os.path.splitext(video_path)[0]}_thumbnail.jpg"
 
         try:
             (
@@ -160,10 +163,10 @@ class VideoProcessor:
         获取视频信息
 
         Args:
-            video_path: 视频文件路径
+            video_path: 视频路径
 
         Returns:
-            视频元数据字典
+            视频信息字典
         """
         try:
             probe = ffmpeg.probe(video_path)