Use Docker in Python and IPython

This article mainly introduces how to use Docker in Python and IPython. Docker is an attractive new system that can be used to build interesting new technology applications, especially cloud services, if you need Docker, you can refer to it. Docker is one of the hottest projects on the Earth, which means that people don't like it because of it.

Even so, I like using containers, service discovery, and all the interesting ideas and fields created to switch jobs as an example.

In this article, I will briefly introduce how to use the docker-py module in python to operate Docker containers. here I will use IPython, my favorite programming tool.

Install docker-py

Docker-py is required first. Note that I will use Ubuntu Trusty 14.04 in this case.

The code is as follows:

$ Pip install docker-py

IPyhton

I really like using IPython to explore Python. It looks like a total of advanced python shells, but more can be done.

The code is as follows:

$ Sudo apt-get install ipython
SNIP!
$ Ipython
Python 2.7.6 (default, Mar 22 2014, 22:59:56)
Type "copyright", "credits" or "license" for more information.

IPython 1.2.1 -- An enhanced Interactive Python.
? -> Introduction and overview of IPython's features.
% Quickref-> Quick reference.
Help-> Python's own help system.
Object? -> Details about 'object', use 'object ?? 'For extra details.

In [1]:

Install docker

If Docker is not installed, first install docker

The code is as follows:

$ Sudo apt-get install docker. io

Start docker. io with an alias docker.

The code is as follows:

$ Alias docker = 'docker. io'
$ Docker version
Client version: 0.9.1
Go version (client): go1.2.1
Git commit (client): 3600720
Server version: 0.9.1
Git commit (server): 3600720
Go version (server): go1.2.1
Last stable version: 0.11.1, please update docker

Docker should now have a socket enabled for connection.

The code is as follows:

$ Ls/var/run/docker. sock
/Var/run/docker. sock

Pull image

Let's download the busybox image

The code is as follows:

$ Docker pull busybox
Pulling repository busybox
71e18d715071: Download complete
98b9fdab1cb6: Download complete
1277aa3f93b3: Download complete
6e0a2595b580: Download complete
2017136ea3c5a: Download complete
B6c0d171bte: Download complete
8464f9ac64e8: Download complete
9798716626f6: Download complete
Fc1343e2fca0: Download complete
F3c823ac7aa6: Download complete

Now we are ready to use docker-py.

Use docker-py

Now we have docker-py, IPython, Docker, and busybox images, we can create some containers.

If you are not familiar with IPython, you can refer to this tutorial (http://ipython.org/ipython-doc/stable/interactive/tutorial.html ),
IPython is very powerful.

First, start IPython and import the docker module.

The code is as follows:

$ Ipython
Python 2.7.6 (default, Mar 22 2014, 22:59:56)
Type "copyright", "credits" or "license" for more information.

IPython 1.2.1 -- An enhanced Interactive Python.
? -> Introduction and overview of IPython's features.
% Quickref-> Quick reference.
Help-> Python's own help system.
Object? -> Details about 'object', use 'object ?? 'For extra details.

In [1]: import docker

Then we create a connection to Docker

The code is as follows:

In [2]: c = docker. Client (base_url = 'unix: // var/run/docker. sock ',
...: Version = '1. 9 ',
...: Timeout = 10)

Now we have connected to Docker.

IPython uses the tab key to complete. If you enter "c." and press the tab key, IPython displays all methods and properties of the Docker connection object.

The code is as follows:

In [3]: c.
C. adapters c. headers c. pull
C. attach c. history c. push
C. attach_socket c. hooks c. put
C. auth c. images c. remove_container
C. base_url c. import_image c. remove_image
C. build c.info c. request
C. cert c. insert c. resolve_redirects
C. close c. inspect_container c. restart
C. commit c. inspect_image c. search
C. containers c. kill c. send
C. cookies c. login c. start
C. copy c. logs c. stop
C. create_container c. max_redirects c. stream
C. create_container_from_config c. mount c. tag
C. delete c. options c. top
C. diff c. params c. trust_env
C. events c. patch c. verify
C. export c. port c. version
C. get c. post c. wait
C. get_adapter c. prepare_request
C. head c. proxies

Let's take a look at c. images. I enter a "?" After c., ipython provides detailed information about this object.

The code is as follows:

In [5]: c. images?
Type: instancemethod
String Form: >
File:/usr/local/lib/python2.7/dist-packages/docker/client. py
Definition: c. images (self, name = None, quiet = False, all = False, viz = False)
Docstring:

Obtain the busybox image.

The code is as follows:

In [6]: c. images (name = "busybox ")
Out [6]:
[{U 'created ': 1401402591,
U'id': u'shanghai ',
U'parentid': u'8464f9ac64e87252a91be3fbb99cee20cda3188de5365bec7975881f389be343 ',
U'repotags': [u'busybox: buildroot-2013.08.1 '],
U'size': 0,
U'virtualsize ': 2489301 },
{U 'created ': 1401402590,
U'id': u'1277aa3f93b3da774690bc4f0d8bf257ff372e23310b4a5dda-3c180c0d64cd5 ',
U'parentid': u'region ',
U'repotags': [u'busybox: ubuntu-14.04 '],
U'size': 0,
U'virtualsize ': 5609404 },
{U 'created ': 1401402589,
U'id': u'shanghai ',
U'parentid': u'region ',
U'repotags': [u'busybox: ubuntu-12.04 '],
U'size': 0,
U'virtualsize ': 5454693 },
{U 'created ': 1401402587,
U'id': u'shanghai ',
U'parentid': u'9798716626f6ae4e6b7f28451c0a1a603dc534fe5d9dd3900150114f89426216 ',
U'repotags': [u'busybox: buildroot-2014.02 ', u'busybox: latest'],
U'size': 0,
U'virtualsize ': 2433303}]

Create a container. Note that I want to add a command that can be run. here the "env" command is used.

The code is as follows:

In [8]: c. create_container (image = "busybox", command = "env ")
Out [8]:
{U'id': u'hangzhou ',
U'warnings': None}

Use ID to start the container

The code is as follows:

In [9]: c. start (container = "container ")

We can check the log to see the output of the configured "env" command when the container is created.

The code is as follows:

In [11]: c. logs (container = "container ")
Out [11]: 'Home =/\ nPATH =/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin: /bin \ nHOSTNAME = 584459a09e6d \ n'

If you use docker command line and use the same command line option to run a container, you can see similar information.

The code is as follows:

$ Docker run busybox env
HOME =/
PATH =/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
HOSTNAME = ce3ad38a52bf

As far as I know, docker-py has no running options. we can create only one container and start it.

The following is a case:

The code is as follows:

In [17]: busybox = c. create_container (image = "busybox", command = "echo hi ")

In [18]: busybox?
Type: dict
String Form: {u'id': u'hangzhou', u'warnings': None}
Length: 2
Docstring:
Dict ()-> new empty dictionary
Dict (mapping)-> new dictionary initialized from a mapping object's
(Key, value) pairs
Dict (iterable)-> new dictionary initialized as if:
D = {}
For k, v in iterable:
D [k] = v
Dict (** kwargs)-> new dictionary initialized with the name = value pairs
In the keyword argument list. For example: dict (one = 1, two = 2)

In [19]: c. start (busybox. get ("Id "))

In [20]: c. logs (busybox. get ("Id "))
Out [20]: 'Hi \ n'

If you have not used a busybox image, we recommend that you use it. I also recommend the jessie image under debain, which is only 120 MB, smaller than the Ubuntu image.

Summary

Docker is an attractive new system that can be used to build interesting new technology applications, especially cloud services. Using IPython, we explored how to use
Docker-py module to create a docker container. Now using python, we can combine docker and easily create many new ideas.