Docker堆栈部署关于顶级对象映射的错误

以下随着Docker入门指南, https: //docs.docker.com/get-started/part3/#your-first-docker-composeyml-file,我遇到了一个问题。 我已经创build了docker-compose.yml文件,并validation了内容是正确的:

version: "3" services: web: image: joshuabelden/get-started:part2 deploy: replicas: 5 resources: limits: cpus: "0.1" memory: 50M restart_policy: condition: on-failure ports: - "80:80" networks: - webnet networks: webnet: 

我也证实,我可以在群外运行我的图像。 运行该命令之后:

  docker stack deploy -c docker-compose.yml getstartedlab 

我收到以下错误:

 Top-level object must be a mapping 

我似乎无法find关于错误信息的任何信息。

你必须添加你的代码应该被复制的“卷”:

 version: "3" services: web: image: iconkam/get-started:part2 deploy: replicas: 5 resources: limits: cpus: "0.1" memory: 50M restart_policy: condition: on-failure volumes: - .:/app ports: - "80:80" networks: - webnet networks: webnet: