使用 needs 语法控制任务依赖

云效流水线 YAML 支持 stages.<stage_id>.jobs.<job_id>.needs 语法定义 Job 依赖。典型场景如下：app1、app2 需要一起构建部署：app1构建任务依赖app1单元测试和app1代码扫描任务都完成，app2构建任务依赖app2单元测试和app2代码扫描任务都完成，app1和app2构建阶段可以并行，用于提升效率；app2部署依赖app1部署完成。上述场景示例 YAML 和运行效果如下：

sources: 
  my_repo1:
    type: gitSample
    name: app1代码源
    endpoint: https://atomgit.com/flow-example/spring-boot.git
    branch: master
  my_repo2:
    type: gitSample
    name: app2代码源
    endpoint: https://atomgit.com/flow-example/node-expressjs.git
    branch: master
defaultWorkspace: my_repo1
stages:
  build_stage:
    name: 构建
    jobs:
      test_job1:
        name: app1单元测试
        steps:
          command_step:
            name: 执行命令
            step: Command
            with:
              run: |
                echo This is build job...
      scan_job1:
        name: app1代码扫描
        steps:
          command_step:
            name: 执行命令
            step: Command
            with:
              run: |
                echo This is build job...
      test_job2:
        name: app2单元测试
        steps:
          command_step:
            name: 执行命令
            step: Command
            with:
              run: |
                echo This is build job...
      scan_job2:
        name: app2代码扫描
        steps:
          command_step:
            name: 执行命令
            step: Command
            with:
              run: |
                echo This is build job...
      build_job1:
        name: app1构建
        # 声明依赖任务，app1构建依赖app1单元测试和代码扫描任务都完成
        needs: 
          - test_job1
          - scan_job1
        steps:
          command_step:
            name: 执行命令
            step: Command
            with:
              run: |
                echo This is build job...
      build_job2:
        name: app2构建
        # 声明依赖任务，app2构建依赖app2单元测试和代码扫描任务都完成
        needs: 
          - test_job2
          - scan_job2
        steps:
          command_step:
            name: 执行命令
            step: Command
            with:
              run: |
                echo This is build job...
  deploy_stage:
    name: 部署
    jobs:
      deploy_job1:
        name: app1部署
        steps:
          command_step:
            name: 执行命令
            step: Command
            with:
              run: echo This is deploy env 1...
      deploy_job2:
        name: app2部署
        # 声明依赖任务，app2部署依赖app1部署任务完成
        needs: deploy_job1
        steps:
          command_step:
            name: 执行命令
            step: Command
            with:
              run: echo This is deploy env 2...