Video Clip MCP

Instructions

Implementation Reference

• src/mcp/server.ts:424-438 (handler)

  MCP tool handler for cancelTask: calls batchManager.cancelTask and returns formatted result

  private async handleCancelTask(args: MCPToolParams['cancelTask']) {
    const success = this.batchManager.cancelTask(args.taskId);
    const result: MCPToolResults['cancelTask'] = {
      success,
      message: success ? '任务已取消' : '任务取消失败或任务不存在'
    };
    return {
      content: [
        {
          type: 'text',
          text: JSON.stringify(result, null, 2),
        },
      ],
    };
  }

• src/mcp/server.ts:311-324 (registration)

  Tool registration/definition for cancelTask in getToolDefinitions() method, including name, description, and input schema

  {
    name: 'cancelTask',
    description: '取消指定的处理任务',
    inputSchema: {
      type: 'object',
      properties: {
        taskId: {
          type: 'string',
          description: '任务ID'
        }
      },
      required: ['taskId']
    }
  },

• src/types/mcp.ts:38-41 (schema)

  TypeScript interface definition for cancelTask input parameters (MCPToolParams['cancelTask'])

  // 取消任务工具参数
  cancelTask: {
    taskId: string;
  };

• src/types/mcp.ts:64-67 (schema)

  TypeScript interface definition for cancelTask output result (MCPToolResults['cancelTask'])

  cancelTask: {
    success: boolean;
    message: string;
  };

• src/core/batch-manager.ts:72-115 (helper)

  BatchManager.cancelTask: handles cancelling pending tasks by removing from queue or processing tasks by calling videoEngine.cancelTask

  public cancelTask(taskId: string): boolean {
    const task = this.tasks.get(taskId);
    if (!task) {
      return false;
    }
  
    if (task.status === 'pending') {
      // 从队列中移除
      const queueIndex = this.processingQueue.indexOf(taskId);
      if (queueIndex > -1) {
        this.processingQueue.splice(queueIndex, 1);
      }
      task.status = 'failed';
      task.result = {
        success: false,
        outputPaths: [],
        duration: 0,
        error: '任务已取消'
      };
      task.completedAt = new Date();
      return true;
    }
  
    if (task.status === 'processing') {
      // 尝试取消正在处理的任务
      const videoEngine = VideoEngine.getInstance();
      const cancelled = videoEngine.cancelTask(taskId);
      if (cancelled) {
        task.status = 'failed';
        task.result = {
          success: false,
          outputPaths: [],
          duration: Date.now() - (task.startedAt?.getTime() || 0),
          error: '任务已取消'
        };
        task.completedAt = new Date();
        this.currentProcessingCount--;
        this.processQueue(); // 继续处理队列
        return true;
      }
    }
  
    return false;
  }

• src/core/video-engine.ts:299-307 (helper)

  VideoEngine.cancelTask: kills the running FFmpeg process for the task if found

  public cancelTask(taskId: string): boolean {
    const task = this.processingTasks.get(taskId);
    if (task) {
      task.kill('SIGKILL');
      this.processingTasks.delete(taskId);
      return true;
    }
    return false;
  }