[Question] Conditional Stopping of Docker Containers

[mickelsonm]

I was wondering how to conditionally stop a docker container. I have a deployment process that I am writing that needs to stop a running docker container if it is running or if it is not running, then it should cleanly exit and continue on.

I tried something like this:

    docker_container "#{app.name}" do
        action :stop
        not_if('sudo docker ps | grep "#{app.name}" | wc -l') 
    end

But that didn't seem to work. I am really new to using Chef and Ruby in general, so any help or step in the right direction would be appreciated. Thanks!

[bflad]

docker_container "name" do
  # ...
  action :stop
end

already does the behavior you mentioned to make writing your cookbooks easy. Here's the code in case you're more curious: https://github.com/bflad/chef-docker/blob/master/providers/container.rb#L96

Let me know if you have additional questions or if its not behaving as expected.

[mickelsonm]

I just tried this:

docker_container "#{app.name}" do
action :stop
end

It doesn't appear to be working as I would expect. Here's the output I got from the test:

Recipe: deployment::none
  * service[webapp] action stop
================================================================================
Error executing action `stop` on resource 'service[webapp]'
================================================================================


Errno::ENOENT
-------------
No such file or directory - /sbin/status webapp


Resource Declaration:
---------------------
# In /home/deployer/chef-solo/cookbooks-2/docker/providers/container.rb

238:   service service_name do
239:     case new_resource.init_type
240:     when 'systemd'
241:       provider Chef::Provider::Service::Systemd
242:     when 'upstart'
243:       provider Chef::Provider::Service::Upstart
244:     end
245:     supports :status => true, :restart => true, :reload => true



Compiled Resource:
------------------
# Declared in /home/deployer/chef-solo/cookbooks-2/docker/providers/container.rb:238:in `service_action'

service("webapp") do
  provider Chef::Provider::Service::Upstart
  action [:stop]
  supports {:status=>true, :restart=>true, :reload=>true}
  retries 0
  retry_delay 2
  service_name "webapp"
  pattern "webapp"
  cookbook_name :"deployment"
  recipe_name "none"
end

[bflad]

Which OS are you on? No such file or directory - /sbin/status seems to imply Upstart isn't installed correctly.

[mickelsonm]

Debian 7, Linux app3 3.2.0-4-amd64 #1 SMP Debian 3.2.51-1 x86_64 GNU/Linux

[bflad]

Ah yeah, Debian uses SysV (init_type sysv in this cookbook) by default. Although the docker_container sysv script is there, no one has contributed an init script for the daemon yet (guess I'll add this to my to-do list tonight). If you're stuck on using Upstart, I believe you need to install the Debian upstart package. I'm not sure if this cookbook should handle that for you by default as it seems outside its duties.

[bflad]

https://packages.debian.org/wheezy/upstart
https://packages.debian.org/wheezy/amd64/upstart/filelist

[mickelsonm]

Thanks for the good information. I am a bit hesitant on adding in upstart when I am planning on using runit, which goes along with issue #72 . Any chance you could incorporate runit into the list for docker functionalities? Thanks.

[bflad]

I'm looking at all the runit documentation now. Should have an initial runit setup hopefully tonight.

[mickelsonm]

Thanks man! Definitely looking forward to it!