Distributor Configuration¶

Web Distributor¶

Type ID: docker_distributor_web

The Web distributor is used to publish a Docker repository in a way that can be consumed and served by Crane directly. By default the redirect files are stored as /var/lib/pulp/published/docker/v1/app/<reponame>.json and /var/lib/pulp/published/docker/v2/app/<reponame>.json for the Docker v1 and v2 content, respectively. The repo data itself is stored in /var/lib/pulp/published/docker/v1/web/<repo_id>/ and /var/lib/pulp/published/docker/v2/web/<repo_id>/.

The global configuration file for the docker_web_distributor plugin can be found in /etc/pulp/server/plugins.conf.d/docker_distributor.json.

All values from the global configuration can be overridden on the local config.

Supported keys¶

docker_publish_directory: The publish directory used for this distributor. The web server should be configured to serve <publish_directory>/v1/web and <publish_directory>/v2/web. The default value is /var/lib/pulp/published/docker.
protected: if “true” requests for this repo will be checked for an entitlement certificate authorizing the server url for this repository; if “false” no authorization checking will be done. This defaults to true.
redirect-url: The server URL that will be used when generating the redirect map for connecting the Docker API to the location the content is stored. The value defaults to https://<server_name_from_pulp_server.conf>/pulp/docker/v1/<repo_name>. This is used for v1 content.
repo-registry-id: The name that should be used for the repository when it is served by Crane. If specified it will be used for the repository field in the redirect file. If a value is not specified, then repository id is used.

Export Distributor¶

Type ID: docker_distributor_export

The export distributor is used to save the contents of a v1 publish into a tar file that can be moved easily for instances where Crane is running on a different server than your Pulp instance. By default the redirect file is stored in the root of the tar file as <reponame>.json, and the repo data itself is stored in the /<repo_id>/ sub directory of the tar file.

The global configuration file for the docker_export_distributor plugin can be found in /etc/pulp/server/plugins.conf.d/docker_distributor_export.json.

All values from the global configuration can be overridden on the local config.

Supported keys¶

docker_publish_directory: The publish directory used for this distributor. The web server should be configured to serve <publish_directory>/export. The default value is /var/lib/pulp/published/docker.
export_file: The fully qualified path and name of the tar file that will be created by the export. This defaults to <docker_publish_directory>/v1/export/repo/<repo_id>.tar
protected: if “true” requests for this repo will be checked for an entitlement certificate authorizing the server url for this repository; if “false” no authorization checking will be done.
redirect-url: The URL where image files for this repository are served. Crane will join this URL with <image_id>/<filename>
repo-registry-id: The name that should be used for the repository when it is served by Crane. If specified it will be used for the repository field in the redirect file. If a value is not specified, then repository id is used. Docker requires that this field contains only lower case letters, integers, hyphens, and periods. Additionally a single slash can be used to namespace the repo.

V2 Redirect File¶

For Docker v2 content, the distributors generate a json file with the details of the repository contents.

The file is JSON formatted with the following keys

type (string) - the type of the file. This will always be “pulp-docker-redirect”.
version (int) - version of the format for the file. For Docker v2, this will be 2.
repository (string) - the name of the repository this file is describing.
repo-registry-id (string) - the name that will be used for this repository in the Docker registry.
url (string) - the url for access to the repository’s content.
protected (bool) - whether or not the repository should be protected by an entitlement certificate.

Example Redirect File Contents:

{
 "type":"pulp-docker-redirect",
 "version":2,
 "repository":"docker",
 "repo-registry-id":"redhat/docker",
 "url":"http://www.foo.com/docker",
 "protected": true
}

V1 Redirect File¶

For legacy Docker v1 content, the distributors generate a json file with the details of the repository contents.

The file is JSON formatted with the following keys

type (string) - the type of the file. This will always be “pulp-docker-redirect”.
version (int) - version of the format for the file. For Docker v1, this will be 1.
repository (string) - the name of the repository this file is describing.
repo-registry-id (string) - the name that will be used for this repository in the Docker registry.
url (string) - the url for access to the repository’s content.
protected (bool) - whether or not the repository should be protected by an entitlement certificate.
images (array) - an array of objects describing each image/layer in the repository.
- id (str) - the image id for the image.
tags (obj) - an object containing key, value paris of “tag-name”:”image-id”.

Example Redirect File Contents:

{
 "type":"pulp-docker-redirect",
 "version":1,
 "repository":"docker",
 "repo-registry-id":"redhat/docker",
 "url":"http://www.foo.com/docker",
 "protected": true,
 "images":[
   {"id":"48e5f45168b97799ad0aafb7e2fef9fac57b5f16f6db7f67ba2000eb947637eb"},
   {"id":"511136ea3c5a64f264b78b5433614aec563103b4d4702f3ba7d4d2698e22c158"},
   {"id":"769b9341d937a3dba9e460f664b4f183a6cecdd62b337220a28b3deb50ee0a02"},
   {"id":"bf747efa0e2fa9f7c691588ce3938944c75607a7bb5e757f7369f86904d97c78"}
   ],
 "tags": {"latest": "769b9341d937a3dba9e460f664b4f183a6cecdd62b337220a28b3deb50ee0a02"}
}

Docker rsync Distributor¶

Purpose:¶

The Docker rsync distributor publishes docker content to a remote server. The distributor uses rsync over ssh to perform the file transfer. Docker images (v1) are published into the root of the remote repository. Manifests (v2) are published into manifests directory and Blobs (v2) are published into blobs directory.

The docker rsync distributor makes it easier to serve docker content on one server and run Crane on another server. It is recommended that the rsync distributor is used required to publish prior to publishing with the docker web distributor.

Configuration¶

Pulp’s SELinux policy includes a pulp_manage_rsync boolean. When enabled, the pulp_manage_rsync boolean allows Pulp to use rsync and make ssh connections. The boolean is disabled by default. The RPM Rsync distributor will fail to publish with SELinux Enforcing unless the boolean is enabled. To enable it, you can do this:

$ sudo semanage boolean --modify --on pulp_manage_rsync

Here is an example docker_rsync_distributor configuration:

{
 "distributor_id": "my_docker_rsync_distributor",
 "distributor_type_id": "docker_rsync_distributor",
 "distributor_config": {
    "remote": {
        "auth_type": "publickey",
        "ssh_user": "foo",
        "ssh_identity_file": "/home/user/.ssh/id_rsa",
        "host": "192.168.121.1",
        "root": "/home/foo/pulp_root_dir"
    },
    "postdistributor_id": "docker_web_distributor_name_cli"
 }
}

postdistributor_id: The id of the docker_distributor_web associated with the same repository. The repo-registry-id configured in the postdistributor will be used when generating tags list. The docker web distributor associated with the same repository is required to have the predistributor_id configured. postdistributor_id is a required config.

The distributor_config contains a remote section with the following settings:

ssh_user

The ssh user for remote server.

ssh_identity_file

Absolute path to the private key that will be used as identity file for ssh. The key must be owned by user apache and must not be readable by other users. If the POSIX permissions are too loose, the SSH application will refuse to use the key. Additionally, if SELinux is Enforcing, Pulp requires the key to be labeled with the httpd_sys_content_t SELinux context. This can be applied to the file with:

$ sudo chcon -t httpd_sys_content_t  /path/to/ssh_identity_file

host

The hostname of the remote server.

root

The absolute path to the remote root directory where all the data (content and published content) lives. This is the remote equivalent to /var/lib/pulp. The repo id is appended to the root path to determine the location of published repository.

Optional Configuration¶

content_units_only: If true, the distributor will publish content units only (e.g. /var/lib/pulp/content). The symlinks of a published repository will not be rsynced.
delete: If true, --delete is appended to the rsync command for symlinks and repodata so that any old files no longer present in the local published directory are removed from the remote server.
remote_units_path: The relative path from the root where unit files will live. Defaults to content/units.
relative_repo_path: The relative path from the root where the repository will be published. Defaults to the repository id.