cluster resource : possible bug in running_nodes method

[alexpop]

I suspect a bug in the running_nodes method since #274.
If cluster_status returns only one running node, running_nodes throws this exception:

Recipe: rabbitmq::cluster
  * rabbitmq_cluster[[{"name":"rabbit@host-1.example.com","type":"disc"},{"name":"rabbit@host-2.example.com","type":"ram"}]] action join

    ================================================================================
    Error executing action `join` on resource 'rabbitmq_cluster[[{"name":"rabbit@host-1.example.com","type":"disc"},{"name":"rabbit@host-2.example.com","type":"ram"}]]'
    ================================================================================

    NoMethodError
    -------------
    undefined method `split' for nil:NilClass

    Cookbook Trace:
    ---------------
    /var/chef/cache/cookbooks/rabbitmq/providers/cluster.rb:83:in `running_nodes'
    /var/chef/cache/cookbooks/rabbitmq/providers/cluster.rb:138:in `joined_cluster?'
    /var/chef/cache/cookbooks/rabbitmq/providers/cluster.rb:201:in `block in class_from_file'

    Resource Declaration:
    ---------------------
    # In /var/chef/cache/cookbooks/rabbitmq/recipes/cluster.rb

     31:     rabbitmq_cluster cluster_nodes do
     32:       action :join
     33:     end
     34:   end

My test node runlist:

    "recipe[rabbitmq::default]",
    "recipe[rabbitmq::user_management]",
    "recipe[rabbitmq::cluster]",
    "recipe[rabbitmq::mgmt_console]"

My masked attributes:

  "override_attributes": {
     "rabbitmq": {
       "version": "3.4.4",
       "default_user": "aaaaaaaa",
       "default_pass": "bbbbbbbb",
       "enabled_users":[{"name":"ccccccccccc","password":"dddddddddd","rights":[{"vhost":null,"conf":".*","write":".*","read":".*"}]}],
       "cluster": true,
       "erlang_cookie": "EEEEEEEEEEEEEEEEEEE",
       "additional_env_settings": ["RABBITMQ_USE_LONGNAME=true"],
       "clustering": {
         "cluster_name": "test1",
         "use_auto_clustering": false,
         "cluster_nodes":[{"name":"rabbit@host-1.example.com","type":"disc"},{"name":"rabbit@host-2.example.com","type":"ram"}]
       }
     }

The exception is caused by gsub!(/'/, '') returning nil if no quotes are found in the match variable.
Based on the chef-shell output, I believe this line:

result = match && match.gsub!(/'/, '').split(',')

with:

result = match && match.gsub(/'/, '')

chef-shell output:

chef (12.4.1)> pattern = '({running_nodes,\[\'*)(.*?)(\'*\]})'
 => "({running_nodes,\\['*)(.*?)('*\\]})" 
chef (12.4.1)>   match = match_pattern_cluster_status(cluster_status, pattern)
 => "rabbit@host-1.example.com" 
chef (12.4.1)> result = match && match.gsub!(/'/, '').split(',')
NoMethodError: undefined method `split' for nil:NilClass
  from (irb):40
  from /opt/chef/embedded/apps/chef/lib/chef/shell.rb:76:in `block in start'
  from /opt/chef/embedded/apps/chef/lib/chef/shell.rb:75:in `catch'
  from /opt/chef/embedded/apps/chef/lib/chef/shell.rb:75:in `start'
  from /opt/chef/embedded/apps/chef/bin/chef-shell:37:in `<top (required)>'
  from /usr/bin/chef-shell:55:in `load'
  from /usr/bin/chef-shell:55:in `<main>'
chef (12.4.1)> match = match_pattern_cluster_status(cluster_status, pattern)
 => "rabbit@host-1.example.com" 
chef (12.4.1)> result = match && match.gsub!(/'/, '')
 => nil 
chef (12.4.1)> match = match_pattern_cluster_status(cluster_status, pattern)
 => "rabbit@host-1.example.com" 
chef (12.4.1)> result = match && match.gsub(/'/, '')
 => "rabbit@host-1.example.com" 
chef (12.4.1)>   Chef::Log.debug("[rabbitmq_cluster] running_nodes : #{result}")
 => [#<Logger:0x000000056fc840 @progname=nil, @level=2, @default_formatter=#<Logger::Formatter:0x000000056fc7c8 @datetime_format=nil>, @formatter=#<Mixlib::Log::Formatter:0x000000056fc638 @datetime_format=nil>, @logdev=#<Logger::LogDevice:0x000000056fc728 @shift_size=nil, @shift_age=nil, @filename=nil, @dev=#<IO:<STDERR>>, @mutex=#<Logger::LogDevice::LogDeviceMutex:0x000000056fc700 @mon_owner=nil, @mon_count=0, @mon_mutex=#<Mutex:0x000000056fc660>>>>] 
chef (12.4.1)>   !result.nil? ? result.split(',') : []
 => ["rabbit@host-1.example.com"]

PR in progress...

[alexpop]

Also fixed by PR #284