Chef Ideas

As a `chef-run` user,

I would like to be able to pass in attributes via the CLI during a `chef-run`,

So that I can parameterize my ad-hoc tasks in a way where I can key off of said attributes, and do action/assignment therein ..

Example use case:

I want to deploy webapp-v1.23 to a target set of nodes using `remote_file` .. This means I would need to update my recipe and execute `chef-run` to make it work as expected .. What I would prefer is to be able to pass in an attribute via the CLI that I can then refer to in my recipe .. For example:

remote_file '/opt/tomcat/webapps/user.war' do
  source "http://nexus.example.com/user-#{node['user_webapp_version']}"
  owner "tomcat"
  group "tomcat"
  mode "0755"
  action :create
end

And the way I would invoke it would be to do something like this:

chef-run webapp-user[1:10]-dev recipes/deploy.rb --node-attr 'user_webapp_version=1.23'

This will enable me to use `chef-run` as my tool of choice via my automation platform (Jenkins, etc.) to perform ad-hoc tasks against target nodes, where I could create an automation "job", pass it parameters, trigger said job, git clone my automation code, and let `chef-run` :dothething: ..

So a possible rebuttal: "Greg, that info should be in code, not as some parameter that is passed in via the CLI, this is not the Chef way" .. I agree !! But since there is no way to generically assign attributes to targets, there is a way where this same feature could be used to key off of a CLI parameter to refer to code .. Here is an example:

# attributes/default.rb
default['user_webapp_version'] = {
  'dev' => 1.23,
  'stage' => 1.22,
  'prod' => 1.21
}

# recipes/deploy.rb
node_enviro = node['node_enviro']

remote_file '/opt/tomcat/webapps/user.war' do
  source "http://nexus.example.com/user-#{node['user_webapp_version'][node_enviro]}"
  owner "tomcat"
  group "tomcat"
  mode "0755"
  action :create
end

And the way I would invoke it would be to do something like this:

chef-run webapp-user[1:10]-dev recipes/deploy.rb --node-attr 'node_enviro="dev"'

Addendum: I want to be able to use this `--node-attr` option multiple times via the same execution .. For example:

chef-run webapp-user[1:10]-dev recipes/deploy.rb --node-attr 'user_webapp_version="1.23"' --node-attr 'restart_webapp=false'