Add docker RHEL7 support

[otahi]

This is a work in progress.

I have found that vagrant-proxyconf docker support does not work on RHEL 7.

• On RHEL 6:
  • docker proxy config is in /etc/sysconfig/docker and it is 'called' from init.
  • it should be export http_proxy=http://myproxy:3128/
• On RHEL 7:
  • docker proxy config is in /etc/sysconfig/docker but it is not 'called' but just 'evaluated' by systemctl.
  • it should be http_proxy=http://myproxy:3128/

I need to do:

• [x] implementation
• [x] tests
  • [x] CentOS 7.0
  • [x] CentOS 6.5
  • [x] Ubuntu 14.04
  • [x] boot2docker

---

On my Mac I tested with this Vagrantfile. (I had already installed some boxes)

Then I have got the result, that means dockers have correct http_proxy environment value.

$ for vm in centos7 centos6 ubuntu14.04 boot2docker ; do echo -n $vm, ; vagrant ssh $vm -c 'sudo cat /proc/`pgrep docker|head -n1`/environ | grep -c http_proxy' 2&> /dev/null ; done
centos7,1
centos6,1
ubuntu14.04,1
boot2docker,1
$

[otahi]

It seems that tests are OK on travis-ci, but coveralls api failed...

test result example:

Finished in 0.366 seconds
243 examples, 0 failures

error on coveralls.

[Coveralls] Submitting to https://coveralls.io/api/v1
[Coveralls] API internal error occured, we're on it!
Coverage is at 72.53%.
Coverage report sent to Coveralls.

I can not rerun the test on travis-ci. Can you rerun them later? > @tmatilai

I can rerun, so I will rerun later..

[otahi]

Sorry I missed following warning. I will fix it.

Methods exceeded maximum allowed ABC complexity (1):

  lib/vagrant-proxyconf/action/configure_docker_proxy.rb  VagrantPlugins::ProxyConf::Action::ConfigureDockerProxy#write_docker_config  18

Total Violations: 1

[otahi]

I have fixed complexity and all above tests passed. Please check it. @tmatilai

[tmatilai]

Thanks @otahi! I'll take a look when I can.

[otahi]

I found this shoud include restarting with systemctl docker restart. I will add it.

[otahi]

I have added systemctl restart docker and passed tests.

[otahi]

@tmatilai How about this one? maybe you are so busy.

[tmatilai]

@otahi sorry, I'm on vacation. And as it's finally warm here, I tend to prefer non-computer activities. But I definitely haven't forgot this. :)

[otahi]

@tmatilai OK. No problem. Have a nice vacation! :smile: