Workflow Engine

DAG-based workflow engine supporting sequential, conditional, and parallel tasks with checkpoint persistence and event-driven execution.

Workflow Engine - OpenClaw 工作流编排引擎

版本: 0.1.0
功能: DAG 执行器 + 条件分支 + 并行执行

功能特性

• DAG 编排: 有向无环图工作流定义
• 顺序执行: 简单的线性任务链
• 条件分支: 支持 if/else 条件判断
• 并行执行: 支持并行任务执行
• 状态持久化: 检查点机制支持断点续执行
• 事件驱动: 完整的事件系统

安装

cd skills/workflow-engine
npm install

快速开始

import { WorkflowEngine } from './src/workflow-engine.js';

// 创建工作流引擎
const engine = new WorkflowEngine({
  checkpointDir: './checkpoints',
  enableCheckpoint: true,
  maxConcurrency: 10
});

// 创建顺序工作流
const dag = engine.createSequentialWorkflow('My Workflow', [
  {
    name: 'Step 1',
    execute: async (context) => {
      console.log('Executing step 1');
      context.data = { value: 42 };
      return { success: true };
    }
  },
  {
    name: 'Step 2',
    execute: async (context) => {
      console.log('Executing step 2');
      console.log('Data from step 1:', context.data);
      return { success: true };
    }
  }
]);

// 执行工作流
const result = await engine.execute(dag.id, {});
console.log('Workflow completed:', result.status);

API 参考

WorkflowEngine

构造函数

new WorkflowEngine(config)

参数:

• config.checkpointDir - 检查点目录（默认：'./checkpoints'）
• config.enableCheckpoint - 启用检查点（默认：true）
• config.maxConcurrency - 最大并发数（默认：10）

createSequentialWorkflow(name, tasks)

创建顺序工作流

const dag = engine.createSequentialWorkflow('Test', [
  { name: 'Task 1', execute: async () => {} },
  { name: 'Task 2', execute: async () => {} }
]);

execute(workflowId, context)

执行工作流

const result = await engine.execute('workflow-id', {
  input: 'data'
});
// 返回: { executionId, status, context, results, duration }

WorkflowDAG

addNode(config)

添加节点

dag.addNode({
  id: 'task1',
  type: 'task', // 'task' | 'condition' | 'parallel' | 'start' | 'end'
  name: 'Task 1',
  execute: async (context) => { return { result: 'done' }; },
  retry: { count: 3, delay: 1000 },
  timeout: 30000
});

addEdge(fromId, toId)

添加边（依赖关系）

dag.addEdge('start', 'task1');
dag.addEdge('task1', 'task2');

topologicalSort()

拓扑排序

const order = dag.topologicalSort();
// 返回: ['start', 'task1', 'task2', 'end']

WorkflowNode

节点类型

• start - 开始节点
• end - 结束节点
• task - 任务节点
• condition - 条件节点
• parallel - 并行节点

节点配置

{
  id: 'unique-id',
  type: 'task',
  name: 'Task Name',
  description: 'Task description',
  execute: async (context) => { /* 执行逻辑 */ },
  retry: { count: 3, delay: 1000 },
  timeout: 30000,
  metadata: {}
}

示例

条件分支

import WorkflowDAG, { WorkflowNode } from './src/dag.js';

const dag = new WorkflowDAG({ name: 'Conditional' });

dag.addNode({ id: 'start', type: 'start' });
dag.addNode({
  id: 'check',
  type: 'condition',
  condition: (ctx) => ctx.value > 10,
  branches: { 'true': 'high', 'false': 'low' }
});
dag.addNode({
  id: 'high',
  type: 'task',
  execute: async () => console.log('High value')
});
dag.addNode({
  id: 'low',
  type: 'task',
  execute: async () => console.log('Low value')
});

dag.addEdge('start', 'check');
dag.addEdge('check', 'high');
dag.addEdge('check', 'low');

并行执行

dag.addNode({ id: 'start', type: 'start' });
dag.addNode({
  id: 'parallel',
  type: 'parallel',
  parallelTasks: ['taskA', 'taskB', 'taskC']
});
dag.addNode({ id: 'taskA', type: 'task', execute: async () => {} });
dag.addNode({ id: 'taskB', type: 'task', execute: async () => {} });
dag.addNode({ id: 'taskC', type: 'task', execute: async () => {} });
dag.addNode({ id: 'merge', type: 'task', execute: async () => {} });

dag.addEdge('start', 'parallel');
dag.addEdge('parallel', 'taskA');
dag.addEdge('parallel', 'taskB');
dag.addEdge('parallel', 'taskC');
dag.addEdge('taskA', 'merge');
dag.addEdge('taskB', 'merge');
dag.addEdge('taskC', 'merge');

事件

engine.on('execution-started', (e) => {
  console.log('Started:', e.executionId);
});

engine.on('execution-completed', (e) => {
  console.log('Completed:', e.executionId, e.state.status);
});

engine.on('node-started', (e) => {
  console.log('Node started:', e.nodeId);
});

engine.on('node-completed', (e) => {
  console.log('Node completed:', e.nodeId);
});

测试

npm test

License

MIT