Docker Registry

Artifactory supports three types of repositories when working with Docker:

• Local repositories are a place for your internal Docker images. Through Artifactory's security capabilities, these are secure private Docker registries.
• Remote repositories are used to proxy remote Docker resources such as Docker Hub.
• Virtual repositories can aggregate multiple Docker registries thus enabling a single endpoint you can use for both pushing and pulling Docker images. This enables the admin to manage the different Docker registries without his users knowing, and continue to work with the same end point.

**Make sure to go to the Advanced tab of each repository and set the Registry Port if you are using the Port method for Docker. Then, the reverse proxy generator should add a new section in for the specified port.

Local Docker Repositories

A local Docker repository is where you can deploy and host your internal Docker images. It is, in effect, a Docker registry able to host collections of tagged Docker images which are your Docker Repositories. Once your images are hosted, you can exercise fine-grained access control, and share them across your organization through replication or by being proxied by repositories in other Artifactory instances.

To define a local Docker repository:

1. From the Administration module, select Repositories | Repositories | Local.
2. Click New Local Repository and select Docker from the Select Package Type dialog. 

3. Set the Repository Key, and in the Docker Settings section, select V2 as the Docker API version.

4. Set Max Unique Tags. This specifies the maximum number of unique tags, per repository, that should be stored for a Docker image. Once the number of tags for an image exceeds this number, older tags will be removed. Leaving the field blank (default) means all tags will be stored.

With Docker, you can proxy a remote Docker registry through remote repositories. A Remote Repositories defined in Artifactory serves as a caching proxy for a registry managed at a remote URL such as https://registry-1.docker.io/ (which is the Docker Hub), or even a Docker repository managed at a remote site by another instance of Artifactory.

Docker images requested from a remote repository are cached on demand. You can remove downloaded images from the remote repository cache, however, you can not manually push Docker images to a remote Docker repository.

To define a remote repository to proxy a remote Docker registry follow the steps below:

Reverse Proxy Settings

Artifactory supports access to Docker registries either through a reverse proxy (using the subdomain method or through port bindings), or using direct access.

When accessing through a reverse proxy, if you are using the Artifactory Reverse Proxy configuration generator you can configure a Docker repository's reverse proxy settings under the Advanced settings tab. For details, please refer to Docker Reverse Proxy Settings.

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Promoting Docker Images

Artifactory supports promoting Docker images from one Docker repository in Artifactory to another. 

Promoting is useful when you need to move Docker images through different acceptance and testing stages, for example, from a development repository, through the different gateways all the way to production. Instead of rebuilding the image multiple times using promotion will ensure the image you will have in your production environment is the one built by your CI server and passed all the relevant tests. 

Promotion can be triggered using the following endpoint with cURL:the following endpoint with cURL:

POST api/docker/<repoKey>/v2/promote
{ 
    "targetRepo" : "<targetRepo>",  
    "dockerRepository" : "<dockerRepository>",  
    "tag" : "<tag>", 
	"targetTag" : "<tag>",
    "copy": <true | false>
}

where:

repoKey	Source repository key
targetRepo	The target repository to move or copy
dockerRepository	The docker repository name to promote
tag	An optional tag name to promote, if null - the entire docker repository will be promoted. Default: latest
targetTag	The new tag that the image should have after being promoted if you want to
copy	When true, a copy of the image is promoted. When false, the image is moved to the target repository

An example for promoting the docker image jfrog/ubuntu"] with all of it's tags from docker-local to docker-prod using cURL would be:

curl -i -uadmin:password -X POST "https://artprod.company.com/v2/promote" -H "Content-Type: application/json" -d '{"tagetRepo":"docker-prod","dockerRepository":"jfrog/ubuntu"}'

Notice that the above example is executed through your reverse proxy. To go directly through Artifactory, you would execute this command as follows:

curl -i -uadmin:password -X POST "http://localhost:8080/artifactory/api/docker/docker-local/v2/promote" -H "Content-Type: application/json" -d '{"targetRepo":"docker-prod","dockerRepository":"jfrog/ubuntu"}'

The following example adds retagging with a specific version of the jfrog/ubuntu image (4.9.0) being retagged to latest as it gets promoted:

curl -i -uadmin:password -X POST "https://artprod.company.com/v2/promote" -H "Content-Type: application/json" -d '{"targetRepo":"docker-prod","dockerRepository":"jfrog/ubuntu", "tag" : "4.9.0", "targetTag" : "latest"}'

Pushing and Pulling Images

Set Me Up

To get the corresponding docker push and docker pull commands for any repository, go to Artifactory | Artifacts | Artifact Repository Browser, in the Application module, and click Set Me Up.

Browsing Docker Repositories

For general information on how to browse repositories, please refer to Browsing Artifactory.

The Docker Info tab presents three sections: Tag Info, Docker Tag Visualization, and Labels.

Tag Info

Presents basic details about the selected tag.

Docker Tag Visualization

This section maps the entire set of commands used to generate the selected tag along with the digest of the corresponding layer. Essentially, you would see the same series of commands using docker history.

You can select any layer of the image to view the following properties.

Symbol	Property
	The layer ID
	The layer size
	The timestamp when the layer was created
	The command that created the layer
	The digest

Labels

This section displays the labels attached to the image.

Note also, that Artifactory extracts any labels associated with a Docker image and creates corresponding properties on the manifest.json file which you can use to specify search parameters, this can be used to easily add additional metadata to any image.

Searching for Docker Images

You can search for Docker images by their name, tag or image digest using the  Artifact Package Search or through the REST API.  

Listing Docker Images

Artifactory supports the following REST API endpoints related to Docker registries:

• List Docker Images provides a list of Docker images in the specified Artifactory Docker registry. This endpoint mimics the Docker _catalog REST API.
• List Docker Tags provides a list of tags for the specified Docker image. 

Artifactory also supports pagination for this endpoint.

To enable fetch from cache using the ListDockerRepositories and the ListDockerTags REST APIs, set the artifactory.docker.catalogs.tags.fallback.fetch.remote.cache system property to true (default false) in the artifactory.system.properties file:

## Enable fetch from cache in Docker repositories
#artifactory.docker.catalogs.tags.fallback.fetch.remote.cache=true

Artifactory needs to be restarted for this change to take effect.

Pushing Images to Bintray

Through Artifactory's close integration with JFrog Bintray, you can push Docker images from your Artifactory Docker Registries directly to Bintray. To enable this, make sure your Bintray credentials are properly configured in your User Profile page. 

To push an image to Bintray, use the Distribution Repository. 

Deletion and Cleanup

Artifactory natively supports removing tags and repositories and complies with the Docker Hub spec.

Deletion of Docker tags and repositories automatically cleans up any orphan layers that are left (layers not used by any other tag/repository).

Currently, the Docker client does not support DELETE commands, but deletion can be triggered manually. To delete an entire Docker repository using cURL, execute the following command:

curl -u<user:password> -X DELETE "<Artifactory URL>/artifactory/<Docker v2 repository name>/<image namespace>"

Or for a specific tag version:

curl -u<user:password> -X DELETE "<Artifactory URL>/artifactory/<Docker v2 repository name>/<image namespace>/<tag>"

For example, to remove the latest tag of an Ubuntu repository:

//Removing the latest tag from the "jfrog/ubuntu" repository
curl -uadmin:password -X DELETE "https://artprod.company.com/artifactory/dockerv2-local/jfrog/ubuntu/latest"

Limiting Unique Tags

To avoid clutter and bloat in your Docker registries caused by many snapshots being uploaded for an image, set the Max Unique Tags field in the Local Docker Repository configuration to limit the number of unique tags. 

Docker Build Information

You may store exhaustive build information in Artifactory by running your Docker builds with JFrog CLI. 

JFrog CLI collects build-info from your build agents and then publishes it to Artifactory. Once published, the build info can be viewed in the  Build Browser under Builds.

For more details on Docker build integration using JFrog CLI, please refer to Building Docker Images in the JFrog CLI User Guide.

Migrating from Docker V1 to Docker V2

If you are still using Docker V1, we strongly recommend upgrading to Docker V2. This requires that you migrate any Docker repositories that were created for Docker V1, and is done with a simple cURL endpoint.

For details, please refer to Migrating a V1 repository to V2 under the Using Docker V1 documentation.