从第 3 方存储库中检索 Docker 个图像标签

Retrieve Docker image tags from a 3rd party repo

对于直接来自 Docker Hub 的 Docker 图像,我可以通过访问它们的存储库 API 来检索图像的当前标签列表。例如,https://registry.hub.docker.com/v1/repositories/python/tags 会给我一个可以与 docker pull python:<tag>.

一起使用的标签列表

对于 Elastic Search,我使用的是他们的官方存储库,可以使用类似 docker pull docker.elastic.co/elasticsearch/elasticsearch:6.4.0

的方式拉取图像

但是,我不知道如何从该存储库中提取标签列表。我试过了

https://docker.elastic.co/elasticsearch/elasticsearch/tags
https://docker.elastic.co/v1/repositories/elasticsearch
https://docker.elastic.co/v2/repositories/elasticsearch/elasticsearch/_manifests/tags

..和其他几个变体。什么 URL/API 端点是 docker 命令行工具在后端请求中将 repository/image 名称翻译成什么?

您可以尝试使用与 python 相同的方法来获取可用版本的标签/列表。

示例:https://registry.hub.docker.com/v1/repositories/elasticsearch/tags

样本输出:[{"layer": "", "name": "1"}, {"layer": "", "name": "1-alpine"}]

所以您要尝试做的是,您将在 shell 脚本中提供标签的供应/显示列表,并要求他们选择。然后基于此,您将在自定义 Docker 文件中执行 docker pull 和 运行 那些命令?

原来docker.elastic.co是运行一个V2docker注册表,所以它需要V2API命令和token认证。尝试最初获取标签会导致 401,其中包含有关如何获取令牌的信息:

http https://docker.elastic.co/v2/elasticsearch/elasticsearch/tags/list                                                                                                                       (566ms)  
HTTP/1.1 401 Unauthorized
Connection: keep-alive
Content-Length: 170
Content-Type: application/json; charset=utf-8
Date: Thu, 09 May 2019 15:24:42 GMT
Docker-Distribution-Api-Version: registry/2.0
Www-Authenticate: Bearer realm="https://docker-auth.elastic.co/auth",service="token-service",scope="repository:elasticsearch/elasticsearch:pull"
X-Content-Type-Options: nosniff

{
    "errors": [
        {
            "code": "UNAUTHORIZED",
            "detail": [
                {
                    "Action": "pull",
                    "Class": "",
                    "Name": "elasticsearch/elasticsearch",
                    "Type": "repository"
                }
            ],
            "message": "authentication required"
        }
    ]
}

使用 WWW-Authenticate 中的信息为给定的 servicescope 请求令牌:

http "https://docker-auth.elastic.co/auth?service=token-service&scope=repository:elasticsearch/elasticsearch:pull"                                                                            (567ms)  
HTTP/1.1 200 OK
Connection: keep-alive
Content-Length: 790
Content-Type: application/json
Date: Thu, 09 May 2019 15:25:37 GMT

{
    "token": "some-long-token"
}

最后,使用令牌发出请求:

http -v https://docker.elastic.co/v2/elasticsearch/elasticsearch/tags/list 'Authorization: Bearer some-long-token'
HTTP/1.1 200 OK
Connection: keep-alive
Content-Length: 1765
Content-Type: application/json; charset=utf-8
Date: Thu, 09 May 2019 15:26:18 GMT
Docker-Distribution-Api-Version: registry/2.0
X-Content-Type-Options: nosniff

{
    "name": "elasticsearch/elasticsearch",
    "tags": [
        "5.0.0-731e78df",
        "5.0.0-86a0b164",
        "5.0.0-alpha5",
        "5.0.0-beta1",
        "5.0.0-ccd69424",
        "5.0.0-rc1",
        "5.0.0",
        ...
        ...
        ...