Handle user option for user selection through docker transport

[Vasu1105]

Signed-off-by: Vasu1105 vasundhara.jagdale@chef.io

Description

For testing created the non root docker image and executed docker run after that executed following train commands.

Before adding user option in the run_command

$ irb -I lib/
2.7.0 :001 > require 'train'
 => true 
2.7.0 :002 > t = Train.create('docker', host: '5f2dbf21d6ee')
 => #<Train::Transports::Docker:0x0000000001526948 @options={:host=>"5f2dbf21d6ee", :shell=>false, :shell_options=>nil, :shell_command=>... 
2.7.0 :003 > c = t.connection
 => Train::Transports::Docker::Connection[unknown] 
2.7.0 :004 > c.run_command("whoami").stdout
 => "john\n" 
2.7.0 :005 > t = Train.create('docker', host: '5f2dbf21d6ee', user: 'root')
 => #<Train::Transports::Docker:0x0000000001cfe030 @options={:host=>"5f2dbf21d6ee", :user=>"root", :shell=>false, :shell_options=>nil, :... 
2.7.0 :006 > c = t.connection
 => Train::Transports::Docker::Connection[unknown] 
2.7.0 :007 > c.run_command("whoami").stdout
 => "john\n" 

Output after adding option in run_command

$ irb -I lib/
2.7.0 :001 > require 'train'
 => true 
2.7.0 :002 > t = Train.create('docker', host: '5f2dbf21d6ee')
 => #<Train::Transports::Docker:0x0000000002129d08 @options={:host=>"5f2dbf21d6ee", :shell=>false, :shell_options=>nil, :shell_command=>... 
2.7.0 :003 > c = t.connection
 => Train::Transports::Docker::Connection[unknown] 
2.7.0 :004 > c.run_command("whoami").stdout
 => "john\n" 
2.7.0 :005 > t = Train.create('docker', host: '5f2dbf21d6ee', user: 'root')
 => #<Train::Transports::Docker:0x000000000201a6b0 @options={:host=>"5f2dbf21d6ee", :user=>"root", :shell=>false, :shell_options=>nil, :... 
2.7.0 :006 > c = t.connection
 => Train::Transports::Docker::Connection[unknown] 
2.7.0 :007 > c.run_command("whoami").stdout
 => "root\n" 

Also tested with the base image where non root user is not configured and following is the output for the same

2.7.0 :001 > require 'train'
 => true 
2.7.0 :002 > t = Train.create('docker', host: '946f59562e28')
 => #<Train::Transports::Docker:0x0000000003066f78 @options={:host=>"946f59562e28", :shell=>false, :shell_options=>nil, :shell_command=>... 
2.7.0 :003 > t.connection
 => Train::Transports::Docker::Connection[unknown] 
2.7.0 :004 > c = t.connection
 => Train::Transports::Docker::Connection[unknown] 
2.7.0 :005 > c.run_command("whoami").stdout
 => "root\n" 

Related Issue

Fixes #574

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New content (non-breaking change)
• Breaking change (a content change which would break existing functionality or processes)

Checklist:

• I have read the CONTRIBUTING document.

[chef-expeditor]

Hello Vasu1105! Thanks for the pull request!

Here is what will happen next:

1. Your PR will be reviewed by the maintainers.
2. Possible Outcomes
   a. If everything looks good, one of them will approve it, and your PR will be merged.
   b. The maintainer may request follow-on work (e.g. code fix, linting, etc). We would encourage you to address this work in 2-3 business days to keep the conversation going and to get your contribution in sooner.
   c. Cases exist where a PR is neither aligned to Chef InSpec's product roadmap, or something the team can own or maintain long-term. In these cases, the maintainer will provide justification and close out the PR.

Thank you for contributing!

[clintoncwolfe]

This works great! Only this I would ask is that we also update the README to document the new option.

[Vasu1105]

This works great! Only this I would ask is that we also update the README to document the new option.

@clintoncwolfe I have updated the docs could you please have a look and let me know any changes required.

[clintoncwolfe]

Thanks!