Docker Remote API v1.9

1. Brief introduction

  • The Remote API has replaced rcli
  • The daemon listens on unix:///var/run/docker.sock but you can bind Docker to another host/port or a Unix socket.
  • The API tends to be REST, but for some complex commands, like attach or pull, the HTTP connection is hijacked to transport stdout, stdin and stderr

2. Endpoints

2.1 Containers

List containers

GET /containers/json

List containers.

Example request:

    GET /containers/json?all=1&before=8dfafdbc3a40&size=1 HTTP/1.1

Example response:

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

    [
         {
                 "Id": "8dfafdbc3a40",
                 "Image": "base:latest",
                 "Command": "echo 1",
                 "Created": 1367854155,
                 "Status": "Exit 0",
                 "Ports":[{"PrivatePort": 2222, "PublicPort": 3333, "Type": "tcp"}],
                 "SizeRw":12288,
                 "SizeRootFs":0
         },
         {
                 "Id": "9cd87474be90",
                 "Image": "base:latest",
                 "Command": "echo 222222",
                 "Created": 1367854155,
                 "Status": "Exit 0",
                 "Ports":[],
                 "SizeRw":12288,
                 "SizeRootFs":0
         },
         {
                 "Id": "3176a2479c92",
                 "Image": "base:latest",
                 "Command": "echo 3333333333333333",
                 "Created": 1367854154,
                 "Status": "Exit 0",
                 "Ports":[],
                 "SizeRw":12288,
                 "SizeRootFs":0
         },
         {
                 "Id": "4cb07b47f9fb",
                 "Image": "base:latest",
                 "Command": "echo 444444444444444444444444444444444",
                 "Created": 1367854152,
                 "Status": "Exit 0",
                 "Ports":[],
                 "SizeRw":12288,
                 "SizeRootFs":0
         }
    ]

Query Parameters:


  • all – 1/True/true or 0/False/false, Show all containers. Only running containers are shown by default (i.e., this defaults to false)
  • limit – Show limit last created containers, include non-running ones.
  • since – Show only containers created since Id, include non-running ones.
  • before – Show only containers created before Id, include non-running ones.
  • size – 1/True/true or 0/False/false, Show the containers sizes

Status Codes:

  • 200 – no error
  • 400 – bad parameter
  • 500 – server error

Create a container

POST /containers/create

Create a container

Example request:

    POST /containers/create HTTP/1.1
    Content-Type: application/json

    {
         "Hostname":"",
         "User":"",
         "Memory":0,
         "MemorySwap":0,
         "CpuShares":0,
         "AttachStdin":false,
         "AttachStdout":true,
         "AttachStderr":true,
         "PortSpecs":null,
         "Tty":false,
         "OpenStdin":false,
         "StdinOnce":false,
         "Env":null,
         "Cmd":[
                 "date"
         ],
         "Dns":null,
         "Image":"base",
         "Volumes":{
                 "/tmp": {}
         },
         "VolumesFrom":"",
         "WorkingDir":"",
         "ExposedPorts":{
                 "22/tcp": {}
         }
    }

Example response:

    HTTP/1.1 201 Created
    Content-Type: application/json

    {
         "Id":"e90e34656806"
         "Warnings":[]
    }

Json Parameters:


  • Hostname – Container host name
  • User – Username or UID
  • Memory – Memory Limit in bytes
  • CpuShares – CPU shares (relative weight)
  • AttachStdin – 1/True/true or 0/False/false, attach to standard input. Default false
  • AttachStdout – 1/True/true or 0/False/false, attach to standard output. Default false
  • AttachStderr – 1/True/true or 0/False/false, attach to standard error. Default false
  • Tty – 1/True/true or 0/False/false, allocate a pseudo-tty. Default false
  • OpenStdin – 1/True/true or 0/False/false, keep stdin open even if not attached. Default false

Query Parameters:


  • name – Assign the specified name to the container. Mus match /?[a-zA-Z0-9_-]+.

Status Codes:

  • 201 – no error
  • 404 – no such container
  • 406 – impossible to attach (container not running)
  • 500 – server error

Inspect a container

GET /containers/(id)/json

Return low-level information on the container id

Example request:

    GET /containers/4fa6e0f0c678/json HTTP/1.1

Example response:

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

    {
                 "Id": "4fa6e0f0c6786287e131c3852c58a2e01cc697a68231826813597e4994f1d6e2",
                 "Created": "2013-05-07T14:51:42.041847+02:00",
                 "Path": "date",
                 "Args": [],
                 "Config": {
                         "Hostname": "4fa6e0f0c678",
                         "User": "",
                         "Memory": 0,
                         "MemorySwap": 0,
                         "AttachStdin": false,
                         "AttachStdout": true,
                         "AttachStderr": true,
                         "PortSpecs": null,
                         "Tty": false,
                         "OpenStdin": false,
                         "StdinOnce": false,
                         "Env": null,
                         "Cmd": [
                                 "date"
                         ],
                         "Dns": null,
                         "Image": "base",
                         "Volumes": {},
                         "VolumesFrom": "",
                         "WorkingDir":""

                 },
                 "State": {
                         "Running": false,
                         "Pid": 0,
                         "ExitCode": 0,
                         "StartedAt": "2013-05-07T14:51:42.087658+02:01360",
                         "Ghost": false
                 },
                 "Image": "b750fe79269d2ec9a3c593ef05b4332b1d1a02a62b4accb2c21d589ff2f5f2dc",
                 "NetworkSettings": {
                         "IpAddress": "",
                         "IpPrefixLen": 0,
                         "Gateway": "",
                         "Bridge": "",
                         "PortMapping": null
                 },
                 "SysInitPath": "/home/kitty/go/src/github.com/docker/docker/bin/docker",
                 "ResolvConfPath": "/etc/resolv.conf",
                 "Volumes": {},
                 "HostConfig": {
                     "Binds": null,
                     "ContainerIDFile": "",
                     "LxcConf": [],
                     "Privileged": false,
                     "PortBindings": {
                        "80/tcp": [
                            {
                                "HostIp": "0.0.0.0",
                                "HostPort": "49153"
                            }
                        ]
                     },
                     "Links": null,
                     "PublishAllPorts": false
                 }
    }

Status Codes:

  • 200 – no error
  • 404 – no such container
  • 500 – server error

List processes running inside a container

GET /containers/(id)/top

List processes running inside the container id

Example request:

    GET /containers/4fa6e0f0c678/top HTTP/1.1

Example response:

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

    {
         "Titles":[
                 "USER",
                 "PID",
                 "%CPU",
                 "%MEM",
                 "VSZ",
                 "RSS",
                 "TTY",
                 "STAT",
                 "START",
                 "TIME",
                 "COMMAND"
                 ],
         "Processes":[
                 ["root","20147","0.0","0.1","18060","1864","pts/4","S","10:06","0:00","bash"],
                 ["root","20271","0.0","0.0","4312","352","pts/4","S+","10:07","0:00","sleep","10"]
         ]
    }

Query Parameters:

  • ps_args – ps arguments to use (e.g., aux)

Status Codes:

  • 200 – no error
  • 404 – no such container
  • 500 – server error

Inspect changes on a container's filesystem

GET /containers/(id)/changes

Inspect changes on container id's filesystem

Example request:

    GET /containers/4fa6e0f0c678/changes HTTP/1.1

Example response:

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

    [
         {
                 "Path":"/dev",
                 "Kind":0
         },
         {
                 "Path":"/dev/kmsg",
                 "Kind":1
         },
         {
                 "Path":"/test",
                 "Kind":1
         }
    ]

Status Codes:

  • 200 – no error
  • 404 – no such container
  • 500 – server error

Export a container

GET /containers/(id)/export

Export the contents of container id

Example request:

    GET /containers/4fa6e0f0c678/export HTTP/1.1

Example response:

    HTTP/1.1 200 OK
    Content-Type: application/octet-stream

    {{ TAR STREAM }}

Status Codes:

  • 200 – no error
  • 404 – no such container
  • 500 – server error

Start a container

POST /containers/(id)/start

Start the container id

Example request:

    POST /containers/(id)/start HTTP/1.1
    Content-Type: application/json

    {
         "Binds":["/tmp:/tmp"],
         "LxcConf":[{"Key":"lxc.utsname","Value":"docker"}],
         "PortBindings":{ "22/tcp": [{ "HostPort": "11022" }] },
         "PublishAllPorts":false,
         "Privileged":false
    }

Example response:

    HTTP/1.1 204 No Conten
    Content-Type: text/plain

Json Parameters:


  • Binds – Create a bind mount to a directory or file with [host-path]:[container-path]:[rw|ro]. If a directory "container-path" is missing, then docker creates a new volume.
  • LxcConf – Map of custom lxc options
  • PortBindings – Expose ports from the container, optionally publishing them via the HostPort flag
  • PublishAllPorts – 1/True/true or 0/False/false, publish all exposed ports to the host interfaces. Default false
  • Privileged – 1/True/true or 0/False/false, give extended privileges to this container. Default false

Status Codes:

  • 204 – no error
  • 404 – no such container
  • 500 – server error

Stop a container

POST /containers/(id)/stop

Stop the container id

Example request:

    POST /containers/e90e34656806/stop?t=5 HTTP/1.1

Example response:

    HTTP/1.1 204 OK

Query Parameters:

  • t – number of seconds to wait before killing the container

Status Codes:

  • 204 – no error
  • 404 – no such container
  • 500 – server error

Restart a container

POST /containers/(id)/restart

Restart the container id

Example request:

    POST /containers/e90e34656806/restart?t=5 HTTP/1.1

Example response:

    HTTP/1.1 204 No Content

Query Parameters:

  • t – number of seconds to wait before killing the container

Status Codes:

  • 204 – no error
  • 404 – no such container
  • 500 – server error

Kill a container

POST /containers/(id)/kill

Kill the container id

Example request:

    POST /containers/e90e34656806/kill HTTP/1.1

Example response:

    HTTP/1.1 204 No Content

Query Parameters

  • signal - Signal to send to the container: integer or string like "SIGINT". When not set, SIGKILL is assumed and the call will wait for the container to exit.

Status Codes:

  • 204 – no error
  • 404 – no such container
  • 500 – server error

Attach to a container

POST /containers/(id)/attach

Attach to the container id

Example request:

    POST /containers/16253994b7c4/attach?logs=1&stream=0&stdout=1 HTTP/1.1

Example response:

    HTTP/1.1 200 OK
    Content-Type: application/vnd.docker.raw-stream

    {{ STREAM }}

Query Parameters:

  • logs – 1/True/true or 0/False/false, return logs. Defaul false
  • stream – 1/True/true or 0/False/false, return stream. Default false
  • stdin – 1/True/true or 0/False/false, if stream=true, attach to stdin. Default false
  • stdout – 1/True/true or 0/False/false, if logs=true, return stdout log, if stream=true, attach to stdout. Default false
  • stderr – 1/True/true or 0/False/false, if logs=true, return stderr log, if stream=true, attach to stderr. Default false

Status Codes:

  • 200 – no error
  • 400 – bad parameter
  • 404 – no such container
  • 500 – server error

    Stream details:

    When using the TTY setting is enabled in POST /containers/create, the stream is the raw data from the process PTY and client's stdin. When the TTY is disabled, then the stream is multiplexed to separate stdout and stderr.

    The format is a Header and a Payload (frame).

    HEADER

    The header will contain the information on which stream write the stream (stdout or stderr). It also contain the size of the associated frame encoded on the last 4 bytes (uint32).

    It is encoded on the first 8 bytes like this:

    header := [8]byte{STREAM_TYPE, 0, 0, 0, SIZE1, SIZE2, SIZE3, SIZE4}
    

    STREAM_TYPE can be:

  • 0: stdin (will be written on stdout)

  • 1: stdou
  • 2: stderr

    SIZE1, SIZE2, SIZE3, SIZE4 are the 4 bytes of the uint32 size encoded as big endian.

    PAYLOAD

    The payload is the raw stream.

    IMPLEMENTATION

    The simplest way to implement the Attach protocol is the following:

    1. Read 8 bytes
    2. chose stdout or stderr depending on the first byte
    3. Extract the frame size from the last 4 byets
    4. Read the extracted size and output it on the correct output
    5. Goto 1)

Wait a container

POST /containers/(id)/wait

Block until container id stops, then returns the exit code

Example request:

    POST /containers/16253994b7c4/wait HTTP/1.1

Example response:

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

    {"StatusCode":0}

Status Codes:

  • 200 – no error
  • 404 – no such container
  • 500 – server error

Remove a container

DELETE /containers/(id)

Remove the container id from the filesystem

Example request:

    DELETE /containers/16253994b7c4?v=1 HTTP/1.1

Example response:

    HTTP/1.1 204 No Content

Query Parameters:

  • v – 1/True/true or 0/False/false, Remove the volumes associated to the container. Default false

Status Codes:

  • 204 – no error
  • 400 – bad parameter
  • 404 – no such container
  • 500 – server error

Copy files or folders from a container

POST /containers/(id)/copy

Copy files or folders of container id

Example request:

    POST /containers/4fa6e0f0c678/copy HTTP/1.1
    Content-Type: application/json

    {
         "Resource":"test.txt"
    }

Example response:

    HTTP/1.1 200 OK
    Content-Type: application/octet-stream

    {{ TAR STREAM }}

Status Codes:

  • 200 – no error
  • 404 – no such container
  • 500 – server error

2.2 Images

List Images

GET /images/json

Example request:

    GET /images/json?all=0 HTTP/1.1

Example response:

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

    [
      {
         "RepoTags": [
           "ubuntu:12.04",
           "ubuntu:precise",
           "ubuntu:latest"
         ],
         "Id": "8dbd9e392a964056420e5d58ca5cc376ef18e2de93b5cc90e868a1bbc8318c1c",
         "Created": 1365714795,
         "Size": 131506275,
         "VirtualSize": 131506275
      },
      {
         "RepoTags": [
           "ubuntu:12.10",
           "ubuntu:quantal"
         ],
         "ParentId": "27cf784147099545",
         "Id": "b750fe79269d2ec9a3c593ef05b4332b1d1a02a62b4accb2c21d589ff2f5f2dc",
         "Created": 1364102658,
         "Size": 24653,
         "VirtualSize": 180116135
      }
    ]

Create an image

POST /images/create

Create an image, either by pull it from the registry or by importing i

Example request:

    POST /images/create?fromImage=base HTTP/1.1

Example response:

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

    {"status":"Pulling..."}
    {"status":"Pulling", "progress":"1 B/ 100 B", "progressDetail":{"current":1, "total":100}}
    {"error":"Invalid..."}
    ...

When using this endpoint to pull an image from the registry, the
`X-Registry-Auth` header can be used to include
a base64-encoded AuthConfig object.

Query Parameters:

  • fromImage – name of the image to pull
  • fromSrc – source to import, - means stdin
  • repo – repository
  • tag – tag
  • registry – the registry to pull from

Request Headers:

  • X-Registry-Auth – base64-encoded AuthConfig object

Status Codes:

  • 200 – no error
  • 500 – server error

Insert a file in an image

POST /images/(name)/insert

Insert a file from url in the image name at path

Example request:

    POST /images/test/insert?path=/usr&url=myurl HTTP/1.1

Example response:

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

    {"status":"Inserting..."}
    {"status":"Inserting", "progress":"1/? (n/a)", "progressDetail":{"current":1}}
    {"error":"Invalid..."}
    ...

Query Parameters:

  • url – The url from where the file is taken
  • path – The path where the file is stored

Status Codes:

  • 200 – no error
  • 500 – server error

Inspect an image

GET /images/(name)/json

Return low-level information on the image name

Example request:

    GET /images/base/json HTTP/1.1

Example response:

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

    {
         "id":"b750fe79269d2ec9a3c593ef05b4332b1d1a02a62b4accb2c21d589ff2f5f2dc",
         "parent":"27cf784147099545",
         "created":"2013-03-23T22:24:18.818426-07:00",
         "container":"3d67245a8d72ecf13f33dffac9f79dcdf70f75acb84d308770391510e0c23ad0",
         "container_config":
                 {
                         "Hostname":"",
                         "User":"",
                         "Memory":0,
                         "MemorySwap":0,
                         "AttachStdin":false,
                         "AttachStdout":false,
                         "AttachStderr":false,
                         "PortSpecs":null,
                         "Tty":true,
                         "OpenStdin":true,
                         "StdinOnce":false,
                         "Env":null,
                         "Cmd": ["/bin/bash"],
                         "Dns":null,
                         "Image":"base",
                         "Volumes":null,
                         "VolumesFrom":"",
                         "WorkingDir":""
                 },
         "Size": 6824592
    }

Status Codes:

  • 200 – no error
  • 404 – no such image
  • 500 – server error

Get the history of an image

GET /images/(name)/history

Return the history of the image name

Example request:

    GET /images/base/history HTTP/1.1

Example response:

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

    [
         {
                 "Id":"b750fe79269d",
                 "Created":1364102658,
                 "CreatedBy":"/bin/bash"
         },
         {
                 "Id":"27cf78414709",
                 "Created":1364068391,
                 "CreatedBy":""
         }
    ]

Status Codes:

  • 200 – no error
  • 404 – no such image
  • 500 – server error

Push an image on the registry

POST /images/(name)/push

Push the image name on the registry

Example request:

    POST /images/test/push HTTP/1.1

Example response:

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

    {"status":"Pushing..."}
    {"status":"Pushing", "progress":"1/? (n/a)", "progressDetail":{"current":1}}}
    {"error":"Invalid..."}
    ...

Request Headers:
  • X-Registry-Auth – include a base64-encoded AuthConfig object.

Status Codes:

  • 200 – no error
  • 404 – no such image
  • 500 – server error

Tag an image into a repository

POST /images/(name)/tag

Tag the image name into a repository

Example request:

    POST /images/test/tag?repo=myrepo&force=0 HTTP/1.1

Example response:

    HTTP/1.1 201 OK

Query Parameters:

  • repo – The repository to tag in
  • force – 1/True/true or 0/False/false, default false

Status Codes:

  • 201 – no error
  • 400 – bad parameter
  • 404 – no such image
  • 409 – conflict
  • 500 – server error

Remove an image

DELETE /images/(name*) : Remove the imagename` from the filesystem

Example request:

    DELETE /images/test HTTP/1.1

Example response:

    HTTP/1.1 200 OK
    Content-type: application/json

    [
     {"Untagged":"3e2f21a89f"},
     {"Deleted":"3e2f21a89f"},
     {"Deleted":"53b4f83ac9"}
    ]

Status Codes:

  • 200 – no error
  • 404 – no such image
  • 409 – conflict
  • 500 – server error

Search images

GET /images/search

Search for an image on Docker Hub.

Note: The response keys have changed from API v1.6 to reflect the JSON sent by the registry server to the docker daemon's request.

Example request:

    GET /images/search?term=sshd HTTP/1.1

Example response:

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

    [
            {
                "description": "",
                "is_official": false,
                "is_trusted": false,
                "name": "wma55/u1210sshd",
                "star_count": 0
            },
            {
                "description": "",
                "is_official": false,
                "is_trusted": false,
                "name": "jdswinbank/sshd",
                "star_count": 0
            },
            {
                "description": "",
                "is_official": false,
                "is_trusted": false,
                "name": "vgauthier/sshd",
                "star_count": 0
            }
    ...
    ]

Query Parameters:

  • term – term to search

Status Codes:

  • 200 – no error
  • 500 – server error

2.3 Misc

Build an image from Dockerfile

POST /build

Build an image from Dockerfile using a POST body.

Example request:

    POST /build HTTP/1.1

    {{ TAR STREAM }}

Example response:

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

    {"stream":"Step 1..."}
    {"stream":"..."}
    {"error":"Error...", "errorDetail":{"code": 123, "message": "Error..."}}

The stream must be a tar archive compressed with one of the
following algorithms: identity (no compression), gzip, bzip2, xz.

The archive must include a file called `Dockerfile`

at its root. It may include any number of other files, which will be accessible in the build context (See the ADD build command).

Query Parameters:

  • t – repository name (and optionally a tag) to be applied to the resulting image in case of success
  • q – suppress verbose build output
  • nocache – do not use the cache when building the image
  • rm – Remove intermediate containers after a successful build

    Request Headers:

  • Content-type – should be set to "application/tar".

  • X-Registry-Config – base64-encoded ConfigFile objec

Status Codes:

  • 200 – no error
  • 500 – server error

Check auth configuration

POST /auth

Get the default username and email

Example request:

    POST /auth HTTP/1.1
    Content-Type: application/json

    {
         "username":"hannibal",
         "password:"xxxx",
         "email":"hannibal@a-team.com",
         "serveraddress":"https://index.docker.io/v1/"
    }

Example response:

    HTTP/1.1 200 OK
    Content-Type: text/plain

Status Codes:

  • 200 – no error
  • 204 – no error
  • 500 – server error

Display system-wide information

GET /info

Display system-wide information

Example request:

    GET /info HTTP/1.1

Example response:

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

    {
         "Containers":11,
         "Images":16,
         "Debug":false,
         "NFd": 11,
         "NGoroutines":21,
         "MemoryLimit":true,
         "SwapLimit":false,
         "IPv4Forwarding":true
    }

Status Codes:

  • 200 – no error
  • 500 – server error

Show the docker version information

GET /version

Show the docker version information

Example request:

    GET /version HTTP/1.1

Example response:

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

    {
         "Version":"0.2.2",
         "GitCommit":"5a2a5cc+CHANGES",
         "GoVersion":"go1.0.3"
    }

Status Codes:

  • 200 – no error
  • 500 – server error

Create a new image from a container's changes

POST /commit

Create a new image from a container's changes

Example request:

    POST /commit?container=44c004db4b17&m=message&repo=myrepo HTTP/1.1
    Content-Type: application/json

    {
         "Hostname":"",
         "User":"",
         "Memory":0,
         "MemorySwap":0,
         "AttachStdin":false,
         "AttachStdout":true,
         "AttachStderr":true,
         "PortSpecs":null,
         "Tty":false,
         "OpenStdin":false,
         "StdinOnce":false,
         "Env":null,
         "Cmd":[
                 "date"
         ],
         "Volumes":{
                 "/tmp": {}
         },
         "WorkingDir":"",
         "DisableNetwork": false,
         "ExposedPorts":{
                 "22/tcp": {}
         }
    }

Example response:

    HTTP/1.1 201 Created
    Content-Type: application/vnd.docker.raw-stream

    {"Id":"596069db4bf5"}

Json Parameters:

  • config - the container's configuration

Query Parameters:

  • container – source container
  • repo – repository
  • tag – tag
  • m – commit message
  • author – author (e.g., "John Hannibal Smith <hannibal@a-team.com>")

Status Codes:

  • 201 – no error
  • 404 – no such container
  • 500 – server error

Monitor Docker's events

GET /events

Get events from docker, either in real time via streaming, or via polling (using since)

Example request:

    GET /events?since=1374067924

Example response:

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

    {"status":"create","id":"dfdf82bd3881","from":"base:latest","time":1374067924}
    {"status":"start","id":"dfdf82bd3881","from":"base:latest","time":1374067924}
    {"status":"stop","id":"dfdf82bd3881","from":"base:latest","time":1374067966}
    {"status":"destroy","id":"dfdf82bd3881","from":"base:latest","time":1374067970}

Query Parameters:

  • since – timestamp used for polling

Status Codes:

  • 200 – no error
  • 500 – server error

Get a tarball containing all images and tags in a repository

GET /images/(name)/get

Get a tarball containing all images and metadata for the repository specified by name.

See the image tarball format for more details.

Example request

    GET /images/ubuntu/get

Example response:

    HTTP/1.1 200 OK
    Content-Type: application/x-tar

    Binary data stream

Status Codes:

  • 200 – no error
  • 500 – server error

Load a tarball with a set of images and tags into docker

POST /images/load

Load a set of images and tags into the docker repository.

See the image tarball format for more details.

Example request

    POST /images/load

    Tarball in body

Example response:

    HTTP/1.1 200 OK

Status Codes:

  • 200 – no error
  • 500 – server error

Image tarball format

An image tarball contains one directory per image layer (named using its long ID), each containing three files:

  1. VERSION: currently 1.0 - the file format version
  2. json: detailed layer information, similar to docker inspect layer_id
  3. layer.tar: A tarfile containing the filesystem changes in this layer

The layer.tar file will contain aufs style .wh..wh.aufs files and directories for storing attribute changes and deletions.

If the tarball defines a repository, there will also be a repositories file at the root that contains a list of repository and tag names mapped to layer IDs.

{"hello-world":
    {"latest":"565a9d68a73f6706862bfe8409a7f659776d4d60a8d096eb4a3cbce6999cc2a1"}
}

3. Going further

3.1 Inside docker run

Here are the steps of docker run :

  • Create the container

  • If the status code is 404, it means the image doesn't exist:

  • Try to pull it

  • Then retry to create the container

  • Start the container

  • If you are not in detached mode:

  • Attach to the container, using logs=1 (to have stdout and

  • stderr from the container's start) and stream=1

  • If in detached mode or only stdin is attached:

  • Display the container's id

3.2 Hijacking

In this version of the API, /attach, uses hijacking to transport stdin, stdout and stderr on the same socket. This might change in the future.

3.3 CORS Requests

To enable cross origin requests to the remote api add the flag "--api-enable-cors" when running docker in daemon mode.

$ docker -d -H="192.168.1.9:2375" --api-enable-cors