Docker registry V2 推送镜像、拉取镜像、搜索镜像、删除镜像和垃圾回收

男娘i 2022-05-22 04:51 369阅读 0赞

*  官方文档
 *  Registry操作
    
     *  推送一个镜像到registry
     *  从registry拉取一个镜像
     *  在registry中搜索一个镜像
     *  删除registry中的镜像
     *  垃圾回收
 *  参考文档

# 官方文档 #

*  [Docker Registry HTTP API V2][]
 *  [Garbage collection][]

# Registry操作 #

## 推送一个镜像到registry ##

# docker push <registry_ip>:<registry_port>/<image_name>:<image_tag>
    docker push 192.168.37.100:5000/busybox:0.0.1

## 从registry拉取一个镜像 ##

# docker pull <registry_ip>:<registry_port>/<image_name>:<image_tag>
    docker pull 192.168.37.100:5000/busybox:0.0.1

## 在registry中搜索一个镜像 ##

Registry V2 不支持通过`docker search` 去搜索镜像。

如果执行下面的命令会遇到“Error response from daemon: Unexpected status code 404” 的错误。

docker search 192.168.37.100:5000/busybox

需要通过Registry V2的REST API去查询。

列出所有的镜像仓库（repositories):

# curl -X GET http://<registry_ip>:<registry_port>/v2/_catalog
    curl -X GET http://192.168.37.100:5000/v2/_catalog

输出例子：

{"repositories":["busybox"]}

列出指定镜像的所有标签：

# curl -X GET http://<registry_ip>:<registry_port>/v2/<image_name>/tags/list
    curl -X GET http://192.168.37.100:5000/v2/busybox/tags/list

输出例子：

{"name":"busybox","tags":["latest","0.0.1","0.0.2"]}

## 删除registry中的镜像 ##

删除registry比较复杂，需要先查到指定标签的镜像的digest (sha256校验和），再根据这个digest来删除。

下面以删除192.168.37.100:5000/busybox/:0.0.1 镜像为例。

先执行以下命令找到该镜像的digest：

curl -v --silent -H "Accept: application/vnd.docker.distribution.manifest.v2+json" -X GET  http://192.168.37.100:5000/v2/busybox/manifests/0.0.1 2>&1 | grep Docker-Content-Digest | awk '{print ($3)}'

Digest输出例子：

Docker-Content-Digest: sha256:74f634b1bc1bd74535d5209589734efbd44a25f4e2dc96d78784576a3eb5b335

执行以下命令，根据digest删除镜像：

curl -v --silent -H "Accept: application/vnd.docker.distribution.manifest.v2+json" -X DELETE http://192.168.37.100:5000/v2/busybox/manifests/sha256:74f634b1bc1bd74535d5209589734efbd44a25f4e2dc96d78784576a3eb5b335

这里的删除镜像只是删除了一些元数据，需要执行下面的垃圾回收才能真正地从硬盘上删除镜像数据。

因为缺省Docker private registry不允许删除镜像，如果遇到“405 Unsupported” 错误，需要在运行registry容器时设置REGISTRY\_STORAGE\_DELETE\_ENABLED环境变量或参数为true。

docker-compose.yaml 例子：

environment:
        REGISTRY_STORAGE_DELETE_ENABLED: "true"

`docker run` 例子：

-e REGISTRY_STORAGE_DELETE_ENABLED="true"

创建Docker private registry可以参考：[一键搭建Docker private registry并使用阿里云镜像加速器][Docker private registry]

## 垃圾回收 ##

进入registry容器，执行`garbage-collect` 命令执行垃圾回收。

docker exec -it registry  /bin/registry garbage-collect  /etc/docker/registry/config.yml

# 参考文档 #

*  《Docker容器与容器云》 3.5 Docker镜像管理，3.6.1 Docker镜像元数据管理
 *  [https://stackoverflow.com/questions/31251356/how-to-get-a-list-of-images-on-docker-registry-v2][https_stackoverflow.com_questions_31251356_how-to-get-a-list-of-images-on-docker-registry-v2]
 *  [https://stackoverflow.com/questions/37033055/how-can-i-use-the-docker-registry-api-v2-to-delete-an-image-from-a-private-regis][https_stackoverflow.com_questions_37033055_how-can-i-use-the-docker-registry-api-v2-to-delete-an-image-from-a-private-regis]
 *  [https://stackoverflow.com/questions/25436742/how-to-delete-images-from-a-private-docker-registry][https_stackoverflow.com_questions_25436742_how-to-delete-images-from-a-private-docker-registry]
 *  [https://github.com/docker/distribution/issues/1326][https_github.com_docker_distribution_issues_1326]
 *  [https://github.com/docker/distribution/issues/989][https_github.com_docker_distribution_issues_989]

[Docker Registry HTTP API V2]: https://docs.docker.com/registry/spec/api/
[Garbage collection]: https://docs.docker.com/registry/garbage-collection/#run-garbage-collection
[Docker private registry]: https://blog.csdn.net/nklinsirui/article/details/80676380
[https_stackoverflow.com_questions_31251356_how-to-get-a-list-of-images-on-docker-registry-v2]: https://stackoverflow.com/questions/31251356/how-to-get-a-list-of-images-on-docker-registry-v2
[https_stackoverflow.com_questions_37033055_how-can-i-use-the-docker-registry-api-v2-to-delete-an-image-from-a-private-regis]: https://stackoverflow.com/questions/37033055/how-can-i-use-the-docker-registry-api-v2-to-delete-an-image-from-a-private-regis
[https_stackoverflow.com_questions_25436742_how-to-delete-images-from-a-private-docker-registry]: https://stackoverflow.com/questions/25436742/how-to-delete-images-from-a-private-docker-registry
[https_github.com_docker_distribution_issues_1326]: https://github.com/docker/distribution/issues/1326
[https_github.com_docker_distribution_issues_989]: https://github.com/docker/distribution/issues/989