moby--moby/docs/reference/api/registry_api.md

Docker Registry API v1

Introduction

• This is the REST API for the Docker Registry 1.0
• It stores the images and the graph for a set of repositories
• It does not have user accounts data
• It has no notion of user accounts or authorization
• It delegates authentication and authorization to the Index Auth service using tokens
• It supports different storage backends (S3, cloud files, local FS)
• It doesn't have a local database
• The registry is open source: Docker Registry

We expect that there will be multiple registries out there. To help to grasp the context, here are some examples of registries:

• sponsor registry: such a registry is provided by a third-party hosting infrastructure as a convenience for their customers and the Docker community as a whole. Its costs are supported by the third party, but the management and operation of the registry are supported by Docker. It features read/write access, and delegates authentication and authorization to the Index.
• mirror registry: such a registry is provided by a third-party hosting infrastructure but is targeted at their customers only. Some mechanism (unspecified to date) ensures that public images are pulled from a sponsor registry to the mirror registry, to make sure that the customers of the third-party provider can docker pull those images locally.
• vendor registry: such a registry is provided by a software vendor, who wants to distribute Docker images. It would be operated and managed by the vendor. Only users authorized by the vendor would be able to get write access. Some images would be public (accessible for anyone), others private (accessible only for authorized users). Authentication and authorization would be delegated to the Index. The goal of vendor registries is to let someone do docker pull basho/riak1.3 and automatically push from the vendor registry (instead of a sponsor registry); i.e., get all the convenience of a sponsor registry, while retaining control on the asset distribution.
• private registry: such a registry is located behind a firewall, or protected by an additional security layer (HTTP authorization, SSL client-side certificates, IP address authorization...). The registry is operated by a private entity, outside of Docker's control. It can optionally delegate additional authorization to the Index, but it is not mandatory.

Note

: Mirror registries and private registries which do not use the Index don't even need to run the registry code. They can be implemented by any kind of transport implementing HTTP GET and PUT. Read-only registries can be powered by a simple static HTTPS server.

Note

: The latter implies that while HTTP is the protocol of choice for a registry, multiple schemes are possible (and in some cases, trivial):

• HTTP with GET (and PUT for read-write registries);
• local mount point;
• remote Docker addressed through SSH.

The latter would only require two new commands in Docker, e.g., registryget and registryput, wrapping access to the local filesystem (and optionally doing consistency checks). Authentication and authorization are then delegated to SSH (e.g., with public keys).

Note

: Private registry servers that expose an HTTP endpoint need to be secured with TLS (preferably TLSv1.2, but at least TLSv1.0). Make sure to put the CA certificate at /etc/docker/certs.d/my.registry.com:5000/ca.crt on the Docker host, so that the daemon can securely access the private registry. Support for SSLv3 and lower is not available due to security issues.

The default namespace for a private repository is library.

Endpoints

Images

Get image layer

GET /v1/images/(image_id)/layer

Get image layer for a given image_id

Example Request:

    GET /v1/images/088b4505aa3adc3d35e79c031fa126b403200f02f51920fbd9b7c503e87c7a2c/layer HTTP/1.1
    Host: registry-1.docker.io
    Accept: application/json
    Content-Type: application/json
    Authorization: Token signature=123abc,repository="foo/bar",access=read

Parameters:

• image_id – the id for the layer you want to get

Example Response:

    HTTP/1.1 200
    Vary: Accept
    X-Docker-Registry-Version: 0.6.0
    Cookie: (Cookie provided by the Registry)

    {layer binary data stream}

Status Codes:

• 200 – OK
• 401 – Requires authorization
• 404 – Image not found

Put image layer

PUT /v1/images/(image_id)/layer

Put image layer for a given image_id

Example Request:

    PUT /v1/images/088b4505aa3adc3d35e79c031fa126b403200f02f51920fbd9b7c503e87c7a2c/layer HTTP/1.1
    Host: registry-1.docker.io
    Transfer-Encoding: chunked
    Authorization: Token signature=123abc,repository="foo/bar",access=write

    {layer binary data stream}

Parameters:

• image_id – the id for the layer you want to get

Example Response:

    HTTP/1.1 200
    Vary: Accept
    Content-Type: application/json
    X-Docker-Registry-Version: 0.6.0

    ""

Status Codes:

• 200 – OK
• 401 – Requires authorization
• 404 – Image not found

Image

Put image layer

PUT /v1/images/(image_id)/json

Put image for a given image_id

Example Request:

    PUT /v1/images/088b4505aa3adc3d35e79c031fa126b403200f02f51920fbd9b7c503e87c7a2c/json HTTP/1.1
    Host: registry-1.docker.io
    Accept: application/json
    Content-Type: application/json
    Cookie: (Cookie provided by the Registry)

    {
        id: "088b4505aa3adc3d35e79c031fa126b403200f02f51920fbd9b7c503e87c7a2c",
        parent: "aeee6396d62273d180a49c96c62e45438d87c7da4a5cf5d2be6bee4e21bc226f",
        created: "2013-04-30T17:46:10.843673+03:00",
        container: "8305672a76cc5e3d168f97221106ced35a76ec7ddbb03209b0f0d96bf74f6ef7",
        container_config: {
            Hostname: "host-test",
            User: "",
            Memory: 0,
            MemorySwap: 0,
            AttachStdin: false,
            AttachStdout: false,
            AttachStderr: false,
            Tty: false,
            OpenStdin: false,
            StdinOnce: false,
            Env: null,
            Cmd: [
            "/bin/bash",
            "-c",
            "apt-get -q -yy -f install libevent-dev"
            ],
            Dns: null,
            Image: "imagename/blah",
            Volumes: { },
            VolumesFrom: ""
        },
        docker_version: "0.1.7"
    }

Parameters:

• image_id – the id for the layer you want to get

Example Response:

    HTTP/1.1 200
    Vary: Accept
    Content-Type: application/json
    X-Docker-Registry-Version: 0.6.0

    ""

Status Codes:

• 200 – OK
• 401 – Requires authorization

Get image layer

GET /v1/images/(image_id)/json

Get image for a given image_id

Example Request:

    GET /v1/images/088b4505aa3adc3d35e79c031fa126b403200f02f51920fbd9b7c503e87c7a2c/json HTTP/1.1
    Host: registry-1.docker.io
    Accept: application/json
    Content-Type: application/json
    Cookie: (Cookie provided by the Registry)

Parameters:

• image_id – the id for the layer you want to get

Example Response:

    HTTP/1.1 200
    Vary: Accept
    Content-Type: application/json
    X-Docker-Registry-Version: 0.6.0
    X-Docker-Size: 456789
    X-Docker-Checksum: b486531f9a779a0c17e3ed29dae8f12c4f9e89cc6f0bc3c38722009fe6857087

    {
        id: "088b4505aa3adc3d35e79c031fa126b403200f02f51920fbd9b7c503e87c7a2c",
        parent: "aeee6396d62273d180a49c96c62e45438d87c7da4a5cf5d2be6bee4e21bc226f",
        created: "2013-04-30T17:46:10.843673+03:00",
        container: "8305672a76cc5e3d168f97221106ced35a76ec7ddbb03209b0f0d96bf74f6ef7",
        container_config: {
            Hostname: "host-test",
            User: "",
            Memory: 0,
            MemorySwap: 0,
            AttachStdin: false,
            AttachStdout: false,
            AttachStderr: false,
            Tty: false,
            OpenStdin: false,
            StdinOnce: false,
            Env: null,
            Cmd: [
            "/bin/bash",
            "-c",
            "apt-get -q -yy -f install libevent-dev"
            ],
            Dns: null,
            Image: "imagename/blah",
            Volumes: { },
            VolumesFrom: ""
        },
        docker_version: "0.1.7"
    }

Status Codes:

• 200 – OK
• 401 – Requires authorization
• 404 – Image not found

Ancestry

Get image ancestry

GET /v1/images/(image_id)/ancestry

Get ancestry for an image given an image_id

Example Request:

    GET /v1/images/088b4505aa3adc3d35e79c031fa126b403200f02f51920fbd9b7c503e87c7a2c/ancestry HTTP/1.1
    Host: registry-1.docker.io
    Accept: application/json
    Content-Type: application/json
    Cookie: (Cookie provided by the Registry)

Parameters:

• image_id – the id for the layer you want to get

Example Response:

    HTTP/1.1 200
    Vary: Accept
    Content-Type: application/json
    X-Docker-Registry-Version: 0.6.0

    ["088b4502f51920fbd9b7c503e87c7a2c05aa3adc3d35e79c031fa126b403200f",
     "aeee63968d87c7da4a5cf5d2be6bee4e21bc226fd62273d180a49c96c62e4543",
     "bfa4c5326bc764280b0863b46a4b20d940bc1897ef9c1dfec060604bdc383280",
     "6ab5893c6927c15a15665191f2c6cf751f5056d8b95ceee32e43c5e8a3648544"]

Status Codes:

• 200 – OK
• 401 – Requires authorization
• 404 – Image not found

Tags

List repository tags

GET /v1/repositories/(namespace)/(repository)/tags

Get all of the tags for the given repo.

Example Request:

    GET /v1/repositories/reynholm/help-system-server/tags HTTP/1.1
    Host: registry-1.docker.io
    Accept: application/json
    Content-Type: application/json
    X-Docker-Registry-Version: 0.6.0
    Cookie: (Cookie provided by the Registry)

Parameters:

• namespace – namespace for the repo
• repository – name for the repo

Example Response:

    HTTP/1.1 200
    Vary: Accept
    Content-Type: application/json
    X-Docker-Registry-Version: 0.6.0

    {
        "latest": "9e89cc6f0bc3c38722009fe6857087b486531f9a779a0c17e3ed29dae8f12c4f",
        "0.1.1":  "b486531f9a779a0c17e3ed29dae8f12c4f9e89cc6f0bc3c38722009fe6857087"
    }

Status Codes:

• 200 – OK
• 401 – Requires authorization
• 404 – Repository not found

Get image id for a particular tag

GET /v1/repositories/(namespace)/(repository)/tags/(tag*)

Get a tag for the given repo.

Example Request:

    GET /v1/repositories/reynholm/help-system-server/tags/latest HTTP/1.1
    Host: registry-1.docker.io
    Accept: application/json
    Content-Type: application/json
    X-Docker-Registry-Version: 0.6.0
    Cookie: (Cookie provided by the Registry)

Parameters:

• namespace – namespace for the repo
• repository – name for the repo
• tag – name of tag you want to get

Example Response:

    HTTP/1.1 200
    Vary: Accept
    Content-Type: application/json
    X-Docker-Registry-Version: 0.6.0

    "9e89cc6f0bc3c38722009fe6857087b486531f9a779a0c17e3ed29dae8f12c4f"

Status Codes:

• 200 – OK
• 401 – Requires authorization
• 404 – Tag not found

Delete a repository tag

DELETE /v1/repositories/(namespace)/(repository)/tags/(tag*)

Delete the tag for the repo

Example Request:

    DELETE /v1/repositories/reynholm/help-system-server/tags/latest HTTP/1.1
    Host: registry-1.docker.io
    Accept: application/json
    Content-Type: application/json
    Cookie: (Cookie provided by the Registry)

Parameters:

• namespace – namespace for the repo
• repository – name for the repo
• tag – name of tag you want to delete

Example Response:

    HTTP/1.1 200
    Vary: Accept
    Content-Type: application/json
    X-Docker-Registry-Version: 0.6.0

    ""

Status Codes:

• 200 – OK
• 401 – Requires authorization
• 404 – Tag not found

Set a tag for a specified image id

PUT /v1/repositories/(namespace)/(repository)/tags/(tag*)

Put a tag for the given repo.

Example Request:

    PUT /v1/repositories/reynholm/help-system-server/tags/latest HTTP/1.1
    Host: registry-1.docker.io
    Accept: application/json
    Content-Type: application/json
    Cookie: (Cookie provided by the Registry)

    "9e89cc6f0bc3c38722009fe6857087b486531f9a779a0c17e3ed29dae8f12c4f"

Parameters:

• namespace – namespace for the repo
• repository – name for the repo
• tag – name of tag you want to add

Example Response:

    HTTP/1.1 200
    Vary: Accept
    Content-Type: application/json
    X-Docker-Registry-Version: 0.6.0

    ""

Status Codes:

• 200 – OK
• 400 – Invalid data
• 401 – Requires authorization
• 404 – Image not found

Repositories

Delete a repository

DELETE /v1/repositories/(namespace)/(repository)/

Delete a repository

Example Request:

    DELETE /v1/repositories/reynholm/help-system-server/ HTTP/1.1
    Host: registry-1.docker.io
    Accept: application/json
    Content-Type: application/json
    Cookie: (Cookie provided by the Registry)

    ""

Parameters:

• namespace – namespace for the repo
• repository – name for the repo

Example Response:

    HTTP/1.1 200
    Vary: Accept
    Content-Type: application/json
    X-Docker-Registry-Version: 0.6.0

    ""

Status Codes:

• 200 – OK
• 401 – Requires authorization
• 404 – Repository not found

Search

If you need to search the index, this is the endpoint you would use.

GET /v1/search

Search the Index given a search term. It accepts

[GET](http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html#sec9.3)
only.

Example request:

    GET /v1/search?q=search_term&page=1&n=25 HTTP/1.1
    Host: index.docker.io
    Accept: application/json

Query Parameters:

• q – what you want to search for
• n - number of results you want returned per page (default: 25, min:1, max:100)
• page - page number of results

Example response:

    HTTP/1.1 200 OK
    Vary: Accept
    Content-Type: application/json

    {"num_pages": 1,
      "num_results": 3,
      "results" : [
         {"name": "ubuntu", "description": "An ubuntu image..."},
         {"name": "centos", "description": "A centos image..."},
         {"name": "fedora", "description": "A fedora image..."}
       ],
      "page_size": 25,
      "query":"search_term",
      "page": 1
     }

Response Items:

• num_pages - Total number of pages returned by query
• num_results - Total number of results returned by query
• results - List of results for the current page
• page_size - How many results returned per page
• query - Your search term
• page - Current page number

Status Codes:

• 200 – no error
• 500 – server error

Status

Status check for registry

GET /v1/_ping

Check status of the registry. This endpoint is also used to determine if the registry supports SSL.

Example Request:

    GET /v1/_ping HTTP/1.1
    Host: registry-1.docker.io
    Accept: application/json
    Content-Type: application/json

    ""

Example Response:

    HTTP/1.1 200
    Vary: Accept
    Content-Type: application/json
    X-Docker-Registry-Version: 0.6.0

    ""

Status Codes:

• 200 – OK

Authorization

This is where we describe the authorization process, including the tokens and cookies.