Add auto cluster configuration support

- added clustername fact and spec tests for it
- added rabbitmq_cluster type and provider with tests
- added related doc
- based from PR#736, credits to @vchepkov

REFERENCE.md

@@ -22,6 +22,7 @@ _Private Classes_
 **Resource types**
 
 * [`rabbitmq_binding`](#rabbitmq_binding): Native type for managing rabbitmq bindings  rabbitmq_binding { 'binding 1':   ensure           => present,   source           => 'myexchange'
+* [`rabbitmq_cluster`](#rabbitmq_cluster): Type to manage a rabbitmq cluster
 * [`rabbitmq_erlang_cookie`](#rabbitmq_erlang_cookie): Type to manage the rabbitmq erlang cookie securely  This is essentially a private type used by the rabbitmq::config class to manage the erlan
 * [`rabbitmq_exchange`](#rabbitmq_exchange): Native type for managing rabbitmq exchanges
 * [`rabbitmq_parameter`](#rabbitmq_parameter): Type for managing rabbitmq parameters
@@ -148,6 +149,21 @@ class { 'rabbitmq':
 }
 ```
 
+To create and join the cluster:
+```puppet
+class { 'rabbitmq':
+  config_cluster           => true,
+  cluster_nodes            => ['rabbit1', 'rabbit2'],
+  cluster                  => {
+    'name'      => 'test_cluster',
+    'init_node' => 'hostname'
+  },
+  cluster_node_type        => 'ram',
+  erlang_cookie            => 'A_SECRET_COOKIE_STRING',
+  wipe_db_on_cookie_change => true,
+}
+```
+
 #### Parameters
 
 The following parameters are available in the `rabbitmq` class.
@@ -213,6 +229,17 @@ Value to set for `cluster_partition_handling` RabbitMQ configuration variable.
 
 Default value: 'ignore'
 
+##### `cluster`
+
+Data type: `Hash`
+
+If both `name` and `init_node` keys are set then the rabbitmq node is added to
+a cluster named after the corresponding key by joining `init_node`.
+Note: `init_node` must be included in the [`cluster_nodes`](#cluster_nodes)
+parameter.
+
+Default value: '{}'
+
 ##### `collect_statistics_interval`
 
 Data type: `Optional[Integer]`
@@ -1132,6 +1159,30 @@ The password to use to connect to rabbitmq
 
 Default value: guest
 
+### rabbitmq_cluster
+
+Type to manage a rabbitmq cluster
+
+#### Properties
+
+The following properties are available in the `rabbitmq_cluster` type.
+
+#### `init_node`
+
+Data type: `String`
+
+The node to join to initiate the cluster. It is mandatory.
+
+Default value: unset
+
+#### `node_disc_type`
+
+Data type: `Enum['ram', 'disc']`
+
+Choose between disc and ram cluster nodes.
+
+Default value: disc
+
 ### rabbitmq_erlang_cookie
 
 Type to manage the rabbitmq erlang cookie securely

data/common.yaml

@@ -2,6 +2,7 @@
 rabbitmq::admin_enable: true
 rabbitmq::management_enable: false
 rabbitmq::use_config_file_for_plugins: false
+rabbitmq::cluster: {}
 rabbitmq::cluster_node_type: 'disc'
 rabbitmq::cluster_nodes: []
 rabbitmq::config: 'rabbitmq/rabbitmq.config.erb'

examples/cluster/join_cluster_and_change_name.pp

@@ -0,0 +1,5 @@
+# This sets the cluster name to `test_cluster`
+# If run on another host than host1, this will join the host1's cluster
+rabbitmq_cluster { 'test_cluster':
+  init_node => 'host1',
+}

lib/facter/rabbitmq_clustername.rb

@@ -0,0 +1,15 @@
+Facter.add(:rabbitmq_clustername) do
+  setcode do
+    if Facter::Util::Resolution.which('rabbitmqctl')
+      ret = nil
+      cluster_status = Facter::Core::Execution.execute('rabbitmqctl -q cluster_status 2>&1')
+      [%r!{cluster_name,<<"(\S+)">>}!, %r!^Cluster name: (\S+)$!].each do |r|
+        if (data = r.match(cluster_status))
+          ret = data[1]
+          break
+        end
+      end
+    end
+    ret
+  end
+end

lib/puppet/provider/rabbitmq_cluster/rabbitmqctl.rb

@@ -0,0 +1,40 @@
+require File.expand_path(File.join(File.dirname(__FILE__), '..', 'rabbitmq_cli'))
+Puppet::Type.type(:rabbitmq_cluster).provide(
+  :rabbitmqctl,
+  parent: Puppet::Provider::RabbitmqCli
+) do
+  confine feature: :posix
+
+  def exists?
+    cluster_name == @resource[:name].to_s
+  end
+
+  def create
+    storage_type = @resource[:node_disc_type].to_s
+
+    init_node = @resource[:init_node].to_s.gsub(%r{^.*@}, '')
+
+    if [Facter.value(:hostname), Facter.value(:fqdn)].include? init_node
+      return rabbitmqctl('set_cluster_name', @resource[:name]) unless cluster_name == resource[:name].to_s
+    else
+      rabbitmqctl('stop_app')
+      rabbitmqctl('join_cluster', "rabbit@#{init_node}", "--#{storage_type}")
+      rabbitmqctl('start_app')
+    end
+  end
+
+  def destroy
+    rabbitmqctl('stop_app')
+    rabbitmqctl('reset')
+    rabbitmqctl('start_app')
+  end
+
+  def cluster_name
+    cluster_status = rabbitmqctl('-q', 'cluster_status')
+    [%r!{cluster_name,<<"(\S+)">>}!, %r!^Cluster name: (\S+)$!].each do |r|
+      if (data = r.match(cluster_status))
+        return data[1]
+      end
+    end
+  end
+end

lib/puppet/type/rabbitmq_cluster.rb

@@ -0,0 +1,50 @@
+Puppet::Type.newtype(:rabbitmq_cluster) do
+  desc <<-DESC
+Native type for managing rabbitmq cluster
+
+@example Configure a cluster, rabbit_cluster
+ rabbitmq_cluster { 'rabbit_cluster':
+   init_node      => 'host1'
+ }
+
+@example Optional parameter tags will set further rabbitmq tags like monitoring, policymaker, etc.
+ To set the cluster name use cluster_name.
+ rabbitmq_cluster { 'rabbit_cluster':
+   init_node      => 'host1',
+   node_disc_type => 'ram',
+ }
+DESC
+
+  ensurable do
+    defaultto(:present)
+    newvalue(:present) do
+      provider.create
+    end
+    newvalue(:absent) do
+      provider.destroy
+    end
+  end
+
+  autorequire(:service) { 'rabbitmq-server' }
+
+  newparam(:name, namevar: true) do
+    desc 'The cluster name'
+  end
+
+  newparam(:init_node) do
+    desc 'Name of which cluster node to join.'
+    validate do |value|
+      resource.validate_init_node(value)
+    end
+  end
+
+  newparam(:node_disc_type) do
+    desc 'Storage type of node, default disc.'
+    newvalues(%r{disc|ram})
+    defaultto('disc')
+  end
+
+  def validate_init_node(value)
+    raise ArgumentError, 'init_node must be defined' if value.empty?
+  end
+end

manifests/init.pp

@@ -72,6 +72,10 @@
 #
 # @example Use RabbitMQ clustering facilities
 #   class { 'rabbitmq':
+#     cluster                  => {
+#       'name'      => 'test_cluster',
+#       'init_node' => 'hostname'
+#     },
 #     config_cluster           => true,
 #     cluster_nodes            => ['rabbit1', 'rabbit2'],
 #     cluster_node_type        => 'ram',
@@ -92,6 +96,7 @@
 #   An array specifying authorization/authentication backend to use. Single quotes should be placed around array entries,
 #   ex. `['{foo, baz}', 'baz']` Defaults to [rabbit_auth_backend_internal], and if using LDAP defaults to [rabbit_auth_backend_internal,
 #   rabbit_auth_backend_ldap].
+# @param cluster Join cluster and change name of cluster.
 # @param cluster_node_type
 #   Choose between disc and ram nodes.
 # @param cluster_nodes
@@ -313,6 +318,7 @@
   Boolean $admin_enable                                                                            = true,
   Boolean $management_enable                                                                       = false,
   Boolean $use_config_file_for_plugins                                                             = false,
+  Hash $cluster                                                                                    = $rabbitmq::cluster,
   Enum['ram', 'disc'] $cluster_node_type                                                           = 'disc',
   Array $cluster_nodes                                                                             = [],
   String $config                                                                                   = 'rabbitmq/rabbitmq.config.erb',
@@ -525,6 +531,15 @@
     Class['rabbitmq::install::rabbitmqadmin'] -> Rabbitmq_exchange<| |>
   }
 
+  if $config_cluster and $cluster['name'] and $cluster['init_node'] {
+    create_resources('rabbitmq_cluster', {
+        $cluster['name'] => {
+          'init_node'      => $cluster['init_node'],
+          'node_disc_type' => $cluster_node_type,
+        }
+    })
+  }
+
   if ($service_restart) {
     Class['rabbitmq::config'] ~> Class['rabbitmq::service']
   }
@@ -535,5 +550,5 @@
   -> Class['rabbitmq::management']
 
   # Make sure the various providers have their requirements in place.
-  Class['rabbitmq::install'] -> Rabbitmq_plugin<| |>
+  Class['rabbitmq::install'] -> Rabbitmq_plugin<| |> -> Rabbitmq_cluster<| |>
 }

spec/acceptance/clustering_spec.rb

@@ -5,9 +5,11 @@
     it 'runs successfully' do
       pp = <<-EOS
       class { 'rabbitmq':
+        cluster                  => { 'name' => 'rabbit_cluster', 'init_node' => $facts['fqdn'] },
         config_cluster           => true,
         cluster_nodes            => ['rabbit1', 'rabbit2'],
         cluster_node_type        => 'ram',
+        environment_variables    => { 'RABBITMQ_USE_LONGNAME' => true },
         erlang_cookie            => 'TESTCOOKIE',
         wipe_db_on_cookie_change => false,
       }
@@ -28,9 +30,11 @@ class { 'erlang': epel_enable => true}
     it 'runs successfully' do
       pp = <<-EOS
       class { 'rabbitmq':
+        cluster                  => { 'name' => 'rabbit_cluster', 'init_node' => $facts['fqdn'] },
         config_cluster           => true,
         cluster_nodes            => ['rabbit1', 'rabbit2'],
         cluster_node_type        => 'ram',
+        environment_variables    => { 'RABBITMQ_USE_LONGNAME' => true },
         erlang_cookie            => 'TESTCOOKIE',
         wipe_db_on_cookie_change => true,
       }
@@ -55,5 +59,17 @@ class { 'erlang': epel_enable => true}
       it { is_expected.to be_file }
       it { is_expected.to contain 'TESTCOOKIE' }
     end
+
+    describe 'rabbitmq_cluster' do
+      context 'cluster_name => rabbit_cluster' do
+        it 'cluster has name' do
+          shell('rabbitmqctl -q cluster_status') do |r|
+            expect(r.stdout).to match(%r!({cluster_name,<<"rabbit_cluster">>}|^Cluster name: rabbit_cluster$)!)
+            expect(r.exit_code).to be_zero
+          end
+          # rubocop:enable RSpec/MultipleExpectations
+        end
+      end
+    end
   end
 end

spec/unit/facter/util/fact_rabbitmq_clustername_spec.rb

@@ -0,0 +1,77 @@
+require 'spec_helper'
+
+describe Facter::Util::Fact do
+  before do
+    Facter.clear
+  end
+
+  describe 'rabbitmq_clusternam' do
+    context 'with value' do
+      it do
+        Facter::Util::Resolution.expects(:which).with('rabbitmqctl').returns(true)
+        Facter::Core::Execution.expects(:execute).with('rabbitmqctl -q cluster_status 2>&1').returns(' {cluster_name,<<"monty">>},')
+        expect(Facter.fact(:rabbitmq_clustername).value).to eq('monty')
+      end
+    end
+
+    context 'with dashes in hostname' do
+      it do
+        Facter::Util::Resolution.expects(:which).with('rabbitmqctl').returns(true)
+        Facter::Core::Execution.expects(:execute).with('rabbitmqctl -q cluster_status 2>&1').returns('Cluster name: rabbit-1')
+        expect(Facter.fact(:rabbitmq_clustername).value).to eq('rabbit-1')
+      end
+    end
+
+    context 'with dashes in clustername/hostname' do
+      it do
+        Facter::Util::Resolution.expects(:which).with('rabbitmqctl').returns(true)
+        Facter::Core::Execution.expects(:execute).with('rabbitmqctl -q cluster_status 2>&1').returns(' {cluster_name,<<"monty-python@rabbit-1">>},')
+        expect(Facter.fact(:rabbitmq_clustername).value).to eq('monty-python@rabbit-1')
+      end
+    end
+
+    context 'with quotes around node name' do
+      it do
+        Facter::Util::Resolution.expects(:which).with('rabbitmqctl').returns(true)
+        Facter::Core::Execution.expects(:execute).with('rabbitmqctl -q cluster_status 2>&1').returns("monty\npython\nCluster name: 'monty@rabbit-1'\nend\nof\nfile")
+        expect(Facter.fact(:rabbitmq_clustername).value).to eq("'monty@rabbit-1'")
+      end
+    end
+
+    context 'rabbitmq is not running' do
+      it do
+        error_string = <<-EOS
+Status of node 'monty@rabbit-1' ...
+Error: unable to connect to node 'monty@rabbit-1': nodedown
+
+DIAGNOSTICS
+===========
+
+attempted to contact: ['monty@rabbit-1']
+
+monty@rabbit-1:
+  * connected to epmd (port 4369) on centos-7-x64
+  * epmd reports: node 'rabbit' not running at all
+                  no other nodes on centos-7-x64
+  * suggestion: start the node
+
+current node details:
+- node name: 'rabbitmq-cli-73@centos-7-x64'
+- home dir: /var/lib/rabbitmq
+- cookie hash: 6WdP0nl6d3HYqA5vTKMkIg==
+
+        EOS
+        Facter::Util::Resolution.expects(:which).with('rabbitmqctl').returns(true)
+        Facter::Core::Execution.expects(:execute).with('rabbitmqctl -q cluster_status 2>&1').returns(error_string)
+        expect(Facter.fact(:rabbitmq_clustername).value).to be_nil
+      end
+    end
+
+    context 'rabbitmqctl is not in path' do
+      it do
+        Facter::Util::Resolution.expects(:which).with('rabbitmqctl').returns(false)
+        expect(Facter.fact(:rabbitmq_clustername).value).to be_nil
+      end
+    end
+  end
+end