c# - 是否可以从Docker容器内部访问任务定义

Question

我希望能够从容器内部访问ECS的task.json中烘焙的某些值。可能吗？我知道我们可以在任务定义中添加environment部分，并且可以在docker容器中引用它，但是我也可以访问其他实体，例如，假设我想从容器内部访问awslogs-group。怎么做？

{
  "family": "task-poc",
  "containerDefinitions": [
    {
      "image": "ABC 123",
      "name": "logging-poc-1",
      "cpu": 1024,
      "memory": 1024,
      "essential": true,
      "logConfiguration": {
        "logDriver": "awslogs",
        "options": {
          "awslogs-group": "my_log_group",
          "awslogs-region": "us-east-1",
          "awslogs-stream-prefix": "foo-transactions-stg-secops"
        }
      }
    }
  ]
}

对于环境变量，我可以像

在C#中- Environment.GetEnvironmentVariable("MyKey");

Answer 1

不，您不能像获取环境变量那样简单地获取日志组，但是可以在下面获取这些指标。

curl $ECS_CONTAINER_METADATA_URI

您可以从应用程序向 get container meta data发出此调用

要么

对于Linux实例:

cat $ECS_CONTAINER_METADATA_FILE

对于Windows实例(PowerShell):

Get-Content -path $env:ECS_CONTAINER_METADATA_FILE

这将返回

The following example shows a container metadata file in the READY status.

{
    "Cluster": "default",
    "ContainerInstanceARN": "arn:aws:ecs:us-west-2:012345678910:container-instance/1f73d099-b914-411c-a9ff-81633b7741dd",
    "TaskARN": "arn:aws:ecs:us-west-2:012345678910:task/2b88376d-aba3-4950-9ddf-bcb0f388a40c",
    "ContainerID": "98e44444008169587b826b4cd76c6732e5899747e753af1e19a35db64f9e9c32",
    "ContainerName": "metadata",
    "DockerContainerName": "/ecs-metadata-7-metadata-f0edfbd6d09fdef20800",
    "ImageID": "sha256:c24f66af34b4d76558f7743109e2476b6325fcf6cc167c6e1e07cd121a22b341",
    "ImageName": "httpd:2.4",
    "PortMappings": [
        {
            "ContainerPort": 80,
            "HostPort": 80,
            "BindIp": "",
            "Protocol": "tcp"
        }
    ],
    "Networks": [
        {
            "NetworkMode": "bridge",
            "IPv4Addresses": [
                "172.17.0.2"
            ]
        }
    ],
    "MetadataFileStatus": "READY"
}

最短方法:

将日志配置的值全部传递给ENV。

        "options": {
          "awslogs-group": "my_log_group",
          "awslogs-region": "us-east-1",
          "awslogs-stream-prefix": "foo-transactions-stg-secops"
        }

将以上内容传递给ENV

          "environment": [
                {
                    "name": "awslogs-group",
                    "value": "my_log_group"
                },
                {
                    "name": "awslogs-region",
                    "value": "us-east-1"
                },
                {
                    "name": "awslogs-stream-prefix",
                    "value": "foo-transactions-stg-secops"
                }
            ],

然后在C#中获得ENV

n C# - Environment.GetEnvironmentVariable("awslogs-group");

很长的路:

从容器元数据d

获取 TaskARN

在应用程序中使用TaskArn描述任务

从describe Task获得任务定义ARN

描述任务定义，您将获得日志组