Recipes¶
Configuring Crane with pulp_docker¶
The Crane project is meant to be used to make Docker repositories hosted by Pulp available
to the Docker client. This allows a docker pull to be performed against data
that is published by the Pulp server.
If Crane is being run on the same server that is running Pulp, there is one setting that
must be configured in Crane in order for it to find the information that is published by Pulp.
In the /etc/crane.conf the data_dir parameter must be set to a location that
contains the app files that are generated during Pulp publish operations.
Pulp places these files in two locations, one for each version of Docker:
/var/lib/pulp/published/docker/v1/app/ and
/var/lib/pulp/published/docker/v2/app/. If you only plan to use one version
of Docker content, you can set Crane’s data_dir setting to point at the
appropriate path. If you plan to serve both, Crane can scan the whole
/var/lib/pulp/published/docker path, filtering for *.json files. Crane
will check the data_dir for updates periodically.
Note
As mentioned above, Crane is able to serve both content version V1 and V2, though it is required to have installed proper docker client version which will be capable to fetch the content. Bear in mind that in newer docker client versions, interaction with V1 registries is deprecated, and since version 1.13 support for the V1 protocol is removed. For more info check docker docs
Full documentation for /etc/crane.conf can be found in the Crane README.
Sync¶
The pulp-docker plugin supports synchronizing from docker V2 API compatible registries.
Warning
index.docker.io is a legacy registry and should be used only for V1 content, along with
--enable-v1 true and --enable-v2 false. Please note however that V1 content is
DEPRECATED and support may removed it at any time.
It is advived to use instead registry-1.docker.io for V2 content!
$ pulp-admin docker repo create --repo-id=synctest --feed=https://registry-1.docker.io --upstream-name=busybox
Repository [synctest] successfully created
$ pulp-admin docker repo sync run --repo-id synctest
+----------------------------------------------------------------------+
Synchronizing Repository [synctest]
+----------------------------------------------------------------------+
This command may be exited via ctrl+c without affecting the request.
Downloading manifests
[\]
... completed
Copying units already in pulp
[-]
... completed
Copying units already in pulp
[-]
... completed
Downloading remote files
[==================================================] 100%
11 of 11 items
... completed
Saving Manifests and Blobs
[-]
... completed
Saving Tags
[-]
... completed
Task Succeeded
Task Succeeded
Once this is complete, the data in the remote repository is now in your local Pulp instance.
Publish¶
The repositories created above can be published for use with Crane.
First the Docker repository name must be specified, which can
be different than the repo_id. The repository name should usually have a
namespace, a /, and then a name. Other than the slash between the namespace and the name,
it is required that this field can contain only lower case letters, integers, hyphens, and periods.
The command below sets the repository name
to pulpdemo/synctest:
$ pulp-admin docker repo update --repo-id=synctest --repo-registry-id=pulpdemo/synctest
This command may be exited via ctrl+c without affecting the request.
[\]
Running...
Updating distributor: docker_web_distributor_name_cli
Task Succeeded
[\]
Running...
Updating distributor: docker_export_distributor_name_cli
Task Succeeded
Then a publish operation can be executed:
$ pulp-admin docker repo publish run --repo-id=synctest
+----------------------------------------------------------------------+
Publishing Repository [synctest]
+----------------------------------------------------------------------+
This command may be exited via ctrl+c without affecting the request.
Task Succeeded
Crane can now be run on the same machine serving the Docker repository through its Docker-registry-like read-only API.
Upload v1 Images to Pulp¶
To upload a Docker v1 Image to Pulp, first you must save its repository with Docker.
Note that the below command saves all of the Images and tags in the busybox
repository to a tarball:
$ sudo docker pull busybox
$ sudo docker save busybox > busybox.tar
Then create a Pulp repository and run an upload command with pulp-admin:
$ pulp-admin docker repo create --repo-id=busybox
Repository [busybox] successfully created
$ pulp-admin docker repo uploads upload --repo-id=busybox -f busybox.tar
+----------------------------------------------------------------------+
Unit Upload
+----------------------------------------------------------------------+
Extracting necessary metadata for each request...
[==================================================] 100%
Analyzing: busybox.tar
... completed
Creating upload requests on the server...
[==================================================] 100%
Initializing: busybox.tar
... completed
Starting upload of selected units. If this process is stopped through ctrl+c,
the uploads will be paused and may be resumed later using the resume command or
canceled entirely using the cancel command.
Uploading: busybox.tar
[==================================================] 100%
2825216/2825216 bytes
... completed
Importing into the repository...
This command may be exited via ctrl+c without affecting the request.
[\]
Running...
Task Succeeded
Deleting the upload request...
... completed
There are now Images in the Pulp repository:
$ pulp-admin docker repo list
+----------------------------------------------------------------------+
Docker Repositories
+----------------------------------------------------------------------+
Id: busybox
Display Name: busybox
Description: None
Content Unit Counts:
Docker Image: 4
Note
The number of Images associated with the repository at this point may differ from the number seen above, but should be at least 1 Image.
During an Image upload, you can specify the id of an ancestor Image that should not be uploaded to the repository. In this case, the masked ancestor and any ancestors of that Image will not be imported:
$ pulp-admin docker repo create --repo-id tutorial
Repository [tutorial] successfully created
$ pulp-admin docker repo uploads upload --repo-id tutorial
-f /home/skarmark/git/pulp1/pulp/tutorial.tar
--mask-id 'f38e479062c4953de709cc7f08fa8f85bec6bc5d01f03e340f7caf2990e8efd1'
+----------------------------------------------------------------------+
Unit Upload
+----------------------------------------------------------------------+
Extracting necessary metadata for each request...
[==================================================] 100%
Analyzing: tutorial.tar
... completed
Creating upload requests on the server...
[==================================================] 100%
Initializing: tutorial.tar
... completed
Starting upload of selected units. If this process is stopped through ctrl+c,
the uploads will be paused and may be resumed later using the resume command or
canceled entirely using the cancel command.
Uploading: tutorial.tar
[==================================================] 100%
353358336/353358336 bytes
... completed
Importing into the repository...
This command may be exited via ctrl+c without affecting the request.
[\]
Running...
Task Succeeded
Deleting the upload request...
... completed
There are now only two Images imported into the Pulp repository, instead of five total Images in the tar file:
$ pulp-admin docker repo list
+----------------------------------------------------------------------+
Docker Repositories
+----------------------------------------------------------------------+
Id: tutorial
Display Name: tutorial
Description: None
Content Unit Counts:
Docker Image: 2
v1 Export¶
The busybox repository can also be exported for a case where Crane will
be run on a different machine, or the Image files will be hosted by another
service:
$ pulp-admin docker repo export run --repo-id=busybox
+----------------------------------------------------------------------+
Publishing Repository [busybox]
+----------------------------------------------------------------------+
This command may be exited via ctrl+c without affecting the request.
Publishing Image Files.
[==================================================] 100%
4 of 4 items
... completed
Saving tar file.
[-]
... completed
Task Succeeded
Note
The number of Images that get published when you try this may differ from the number seen above, but should be at least 1 Image.
This produces a tarball at
/var/lib/pulp/published/docker/v1/export/repo/busybox.tar which contains
both a JSON file for use with crane, and the static Image files to which crane
will redirect requests. See the Crane documentation for how to use that
tarball.
Upload v2 schema 2 and schema 1 Images to Pulp¶
To upload a Docker Image to Pulp, first you must save its repository with Skopeo.
Note that the below command saves the image in the busybox
repository to a directory:
$ skopeo copy --format v2s2 docker://busybox:latest dir:existingemptydirectory
Note
With skopeo copy --format schema version v2s1 or v2s2 can be specified.
If no format is specified manifest type of source will be saved.
Before uploading the image to a Pulp repository, you need to create a tarball
with the directory contents created by skopeo copy:
$ cd existingemptydirectory/ && tar -cvf ../image-name.tar * && cd ..
Note
The tarball is only required to contain blob files for layers referenced in the manifest if they are not already contained in the specified repository. Blob files included in the tarball that are already contained in the repository will be ignored.
Then create a Pulp repository and run an upload command with pulp-admin:
$ pulp-admin docker repo create --repo-id=schema2
Repository [schema2] successfully created
$ pulp-admin docker repo uploads upload --repo-id schema2 -f image-name.tar
+----------------------------------------------------------------------+
Unit Upload
+----------------------------------------------------------------------+
Extracting necessary metadata for each request...
[==================================================] 100%
Analyzing: image-name.tar
... completed
Creating upload requests on the server...
[==================================================] 100%
Initializing: image-name.tar
... completed
Starting upload of selected units. If this process is stopped through ctrl+c,
the uploads will be paused and may be resumed later using the resume command or
canceled entirely using the cancel command.
Uploading: image-name.tar
[==================================================] 100%
737280/737280 bytes
... completed
Importing into the repository...
This command may be exited via ctrl+c without affecting the request.
[\]
Running...
Task Succeeded
Deleting the upload request...
... completed
The Blobs and Manifest are now in the Pulp repository:
+----------------------------------------------------------------------+
Docker Repositories
+----------------------------------------------------------------------+
Id: schema2
Display Name: None
Description: None
Content Unit Counts:
Docker Blob: 2
Docker Manifest: 1
Note
skopeo copy looses all the tags in the repository, therefore the manifests
need to be tagged as a separate step after uploading it.
$ pulp-admin docker repo search manifest --repo-id schema2
Created: 2018-02-14T16:06:12Z
Metadata:
Config Layer: sha256:5b0d59026729b68570d99bc4f3f7c31a2e4f2a5736435641565
d93e7c25bd2c3
Digest: sha256:d5483f2ed144c808d4b077f5ec6821d2b3c378ca6cd5a3a5ef9
927b99ac28f99
Downloaded: True
Fs Layers:
Blob Sum: sha256:57310166fe88e0dc63a80ca5c219283a932db0f3969712e2f8a86ada1
43bf566
Layer Type: application/vnd.docker.image.rootfs.diff.tar.gzip
Pulp User Metadata:
Schema Version: 2
Repo Id: schema2
Unit Id: db9071ed-36f0-44dc-b759-fdf58f065bef
Unit Type Id: docker_manifest
Updated: 2018-02-14T16:06:12Z
Tip
To upload v2 schema 1 image manifest repeat steps mentioned aboved, just specify the format
skopeo copy --format v2s1
Uploading a Manifest List¶
Manifests referenced by the Manifest List must already be associated to the target repository. For this example, start with a synced busybox repository.:
$ pulp-admin docker repo sync run --repo-id busybox
To upload your Manifest List, use the upload command:
$ pulp-admin docker repo uploads upload --repo-id=busybox --manifest-list -f your_manifest_list.json
+----------------------------------------------------------------------+
Unit Upload
+----------------------------------------------------------------------+
Extracting necessary metadata for each request...
[==================================================] 100%
Analyzing: your_manifest_list.json
... completed
Creating upload requests on the server...
[==================================================] 100%
Initializing: your_manifest_list.json
... completed
Starting upload of selected units. If this process is stopped through ctrl+c,
the uploads will be paused and may be resumed later using the resume command or
canceled entirely using the cancel command.
Uploading: your_manifest_list.json
[==================================================] 100%
1358/1358 bytes
... completed
Importing into the repository...
This command may be exited via ctrl+c without affecting the request.
[\]
Running...
Task Succeeded
Deleting the upload request...
... completed
Tagging a Manifest¶
Using the docker repo tag command, we can point a docker tag to a manifest. If
the tag we specify does not exist, it will be created. If the tag exists
however, it will be updated as tag name is unique per repository and can point
to only one manifest.
Note
Pulp now supports image manifest schema 1 and schema 2 versions, same as manifest lists schema 2. So when tagging a manifest( image or list), bear in mind that within a repo there could be two tags with the same name but pointing to manifests with different schema versions.
For instance, suppose we have the following image manifest that is tagged
pulp-admin docker repo search tag --repo-id man-list --str-eq='name=uclibc'
Created: 2017-07-12T11:43:29Z
Metadata:
Manifest Digest: sha256:26b0ddb0504097612cd7ed2265eade43f2490cd111a7cfcf7d1
51dba83b20a5e
Manifest Type: image
Name: uclibc
Pulp User Metadata:
Repo Id: man-list
Schema Version: 1
Repo Id: man-list
Unit Id: a37aa675-194c-4f07-925b-e1e12d98ad85
Unit Type Id: docker_tag
Updated: 2017-07-12T11:43:29Z
If we have a tag named uclibc and it points to the manifest with digest sha256:26b0ddb0…, we can point it to the new manifest with the following command:
$ pulp-admin docker repo tag --repo-id busybox --tag-name latest --digest sha256:c152ddeda2b828fbb610cb9e4cb121e1879dd5301d336f0a6c070b2844a0f56d
We can also create a new tag and point it to the same manifest with:
$ pulp-admin docker repo tag --repo-id busybox --tag-name 1.2 --digest sha256:c152ddeda2b828fbb610cb9e4cb121e1879dd5301d336f0a6c070b2844a0f56d
Copy¶
The docker repo copy command can be used to copy docker v1 and v2 content.
In this recipe, we will go through the copy process of different docker content types
$ pulp-admin docker repo list
+----------------------------------------------------------------------+
Docker Repositories
+----------------------------------------------------------------------+
Id: containers
Display Name: None
Description: None
Content Unit Counts:
Docker Blob: 93
Docker Manifest: 115
Docker Manifest List: 4
Docker Tag: 128
Id: containers2
Display Name: None
Description: None
Content Unit Counts:
Let’s copy all image manifests from repo containers to the destination repo containers2
$ pulp-admin docker repo copy manifest --from-repo-id containers --to-repo-id containers2
This command may be exited via ctrl+c without affecting the request.
[|]
Running...
Copied:
docker_blob: 93
docker_manifest: 115
As you can see during the copy of image manifests, all referenced blobs were carried over as well. Note that tags are lost during the copy of the manifests.
- ::
$ pulp-admin docker repo copy
Usage: pulp-admin [SUB_SECTION, ..] COMMAND Description: content copy commands
- Available Commands:
image - copies images from one repository into another manifest - copies manifests from one repository into another manifest-list - copies manifest lists from one repository into another tag - copies tags from one repository into another
If a manifest list is copied, all listed image manifests within the manifest list and blobs will be carried over. Tags of image manifests will not be copied.
If a tag which references an image manifest is copied, image manifest and all its blobs will be copied over.
If a tag which references a manifest list is copied, the manifest list, all listed image manifests within the manifest list and blobs will be carried over. Tags of images manifests will not be copied.
Remove¶
The docker repo remove command can be used to remove docker v1 and v2 content from the repository.
In this recipe, we will go through the removal process of different docker content types.
Let’s remove a tag with the name latest
$ pulp-admin docker repo remove tag --repo-id containers --str-eq=name=latest
This command may be exited via ctrl+c without affecting the request.
[\]
Running...
Units Removed:
latest
latest
There were removed two tags with the name latest because one tag was referencing an image manifest and the second tag was referencing a manifest list.
In case it is desired to remove a specific tag which references, for example, manifest list, then manifest type should be specified
$ pulp-admin docker repo remove tag --repo-id containers --str-eq=name=glibc --str-eq='manifest_type=list'
This command may be exited via ctrl+c without affecting the request.
[\]
Running...
Units Removed:
glibc
::
$ pulp-admin docker repo remove
Usage: pulp-admin [SUB_SECTION, ..] COMMAND
Description: content removal commands
Available Commands:
image - remove images from a repository
manifest - remove manifests from a repository
manifest-list - remove manifest lists from a repository
tag - remove tags from a repository
If a tag is removed, just the tag itself will be removed from the repository.
If a manifest list is removed, all its image manifests which don’t have tags and are not referenced in any other manifest list will be removed from the repo. Orphaned blobs from removed image manifests will be removed as well.
If an image manifest is removed, all its blobs, which are not referenced in any other image manifests within the repo, will be removed as well.
Warning
Please make sure that when you remove an image manifest, it is not referenced in any manifest lists within the repo, otherwise you risk to corrupt a manifest list.