added support for hostname aliases

attributes/ssh_known_hosts.rb

@@ -2,7 +2,7 @@
 # Cookbook Name:: hosts-awareness
 # Attributes:: ssh_known_hosts
 #
-# Copyright 2011, Rob Lewis <[email protected]>
+# Copyright 2012, Rob Lewis <[email protected]>
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -17,6 +17,8 @@
 # limitations under the License.
 #
 
-default['hosts_aware']['ssh_known_hosts']['file_owner'] = nil
-default['hosts_aware']['ssh_known_hosts']['file_group'] = nil
-default['hosts_aware']['ssh_known_hosts']['all_users'] = false
+default['hosts_awareness']['ssh_known_hosts']['file_owner'] = nil
+
+default['hosts_awareness']['ssh_known_hosts']['file_group'] = nil
+
+default['hosts_awareness']['ssh_known_hosts']['all_users'] = false

libraries/etc_hosts.rb

@@ -2,7 +2,7 @@
 # Cookbook Name:: hosts-awareness
 # Library:: EtcHosts
 #
-# Copyright 2011, Rob Lewis <[email protected]>
+# Copyright 2012, Rob Lewis <[email protected]>
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -32,8 +32,8 @@ def block_token
       @block_token || 'chef nodes'
     end
 
-    def set_hosts(hosts)
-      write_out!(hosts)
+    def set_hosts(hosts, alias_mappings=nil)
+      write_out!(hosts, alias_mappings)
     end
 
     def empty!
@@ -42,38 +42,51 @@ def empty!
 
     protected
 
-    def host_entry(host)
+    def host_entry(host, alias_mappings)
+      aliases = []
+      aliases << (host.has_short_hostname? ? host.short_hostname : '')
+      aliases << host.provider_public_hostname
+      aliases << host.provider_private_hostname
+      aliases.concat(alias_mappings[host.hostname]) unless alias_mappings.nil? || alias_mappings[host.hostname].nil?
+
       if use_private_addresses
-        [host.private_ipv4, host.hostname, host.short_hostname, host.provider_public_hostname, host.provider_private_hostname]
+        [host.private_ipv4, host.hostname] + aliases
       else
-        [host.public_ipv4, host.hostname, host.short_hostname, host.provider_public_hostname, host.provider_private_hostname]
+        [host.public_ipv4, host.hostname] + aliases
       end
     end
 
-    def format_host_entries(hosts)
-      host_entries = hosts.sort{|a,b| a.hostname <=> b.hostname}.collect{|host| host_entry(host)}
-      a = host_entries.transpose
-      a = a.map do |col|
-        w = col.map{|cell| cell.to_s.length}.max
-        col.map{|cell| cell.to_s.ljust(w)}
+    def format_host_entries(hosts, alias_mappings)
+      host_entries = hosts.sort{|a,b| a.hostname <=> b.hostname}.collect{|host| host_entry(host, alias_mappings)}
+      column_widths = []
+      host_entries.each do |row|
+        row.each_with_index do |cell, i|
+          len = cell.to_s.length
+          column_widths[i] = len if column_widths[i].nil? || len > column_widths[i]
+        end
       end
-      a.transpose.inject(''){|s, row| s << row.join('  ').rstrip + "\n"; s}
+      host_entries.map do |row|
+        row.each_with_index.inject('') do |s, (cell, i)|
+          s << cell.to_s.ljust(column_widths[i]+2)
+          s
+        end.rstrip
+      end.join("\n")
     end
 
-    def write_out!(hosts)
-      host_entries_string = format_host_entries(hosts)
+    def write_out!(hosts, alias_mappings=nil)
+      host_entries_string = format_host_entries(hosts, alias_mappings)
       File.open(@etc_hosts_file, 'r+') do |f|
         out, over, seen_tokens = '', false, false
         f.each do |line|
           if line =~ /^#{start_token}/
             over = seen_tokens = true
-            out << line << host_entries_string
+            out << line << host_entries_string << "\n"
           elsif line =~ /^#{end_token}/
             over = false
           end
           out << line unless over
         end
-        if !seen_tokens
+        unless seen_tokens
           out << surround_with_tokens(host_entries_string)
         end
 
@@ -84,7 +97,7 @@ def write_out!(hosts)
     end
 
     def surround_with_tokens(str)
-      "\n#{start_token}\n" + str + "#{end_token}\n"
+      "\n#{start_token}\n" + str + "\n#{end_token}\n"
     end
 
     def start_token()

libraries/host.rb

@@ -2,7 +2,7 @@
 # Cookbook Name:: hosts-awareness
 # Library:: Host
 #
-# Copyright 2011, Rob Lewis <[email protected]>
+# Copyright 2021, Rob Lewis <[email protected]>
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -71,6 +71,10 @@ def short_hostname
       end
     end
 
+    def has_short_hostname?
+      !hostname.eql?(short_hostname)
+    end
+
     def domain_name
       @domain_name ||= @hostname.partition('.').last
     end

libraries/host_aliases.rb

@@ -0,0 +1,54 @@
+#
+# Cookbook Name:: hosts-awareness
+# Library:: HostAliases
+#
+# Copyright 2012, Rob Lewis <[email protected]>
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+require 'chef/mixin/language'
+include Chef::Mixin::Language
+
+module HostsAwareness
+  class HostAliases
+    attr_accessor :alias_mappings
+
+    def self.from_data_bags(mapping_names)
+      all_host_alias_mappings = data_bag('host_aliases')
+      host_aliases = HostsAwareness::HostAliases.new
+      mapping_names.each do |mapping_name|
+        if all_host_alias_mappings.include?(mapping_name)
+          mapping_data_bag_item = data_bag_item('host_aliases', mapping_name)
+          alias_mappings = mapping_data_bag_item['alias_mappings']
+          unless alias_mappings.nil?
+            alias_mappings.each do |hostname, hostname_aliases|
+              if host_aliases.alias_mappings[hostname].nil?
+                host_aliases.alias_mappings[hostname] = Array(hostname_aliases)
+              else
+                host_aliases.alias_mappings[hostname].concat(Array(hostname_aliases))
+              end
+            end
+          end
+        else
+          Chef::Log.error("No data bag entry for host alias mappings \"#{mapping_name}\"")
+        end
+      end
+      host_aliases
+    end
+
+    def initialize
+      @alias_mappings = {}
+    end
+  end
+end

metadata.rb

@@ -4,7 +4,7 @@
 license          'Apache 2.0'
 description      'Installs/Configures hosts-awareness'
 long_description IO.read(File.join(File.dirname(__FILE__), 'README.rdoc'))
-version          '0.0.3'
+version          '0.0.4'
 
 recipe 'hosts-awareness',                  'Includes all recipes'
 recipe 'hosts-awareness::etc_hosts',       'Updates /etc/hosts with node entries.'

recipes/etc_hosts.rb

@@ -2,7 +2,7 @@
 # Cookbook Name:: hosts-awareness
 # Recipe:: etc_hosts
 #
-# Copyright 2011, Rob Lewis <[email protected]>
+# Copyright 2012, Rob Lewis <[email protected]>
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -19,6 +19,10 @@
 
 ruby_block 'update_etc_hosts' do
   block do
+    all_host_alias_mappings = data_bag('host_aliases')
+    host_alias_mappings = node['hosts_awareness'].nil? ? [] : Array(node['hosts_awareness']['host_aliases'])
+    host_alias_mappings = all_host_alias_mappings if host_alias_mappings.first == 'all'
+    alias_mappings = HostsAwareness::HostAliases.from_data_bags(host_alias_mappings).alias_mappings
     all_network_names = data_bag('networks')
     networks = node['hosts_awareness'].nil? ? [] : Array(node['hosts_awareness']['networks'])
     networks = all_network_names if networks.first == 'all'
@@ -27,7 +31,7 @@
       etc_hosts = HostsAwareness::EtcHosts.new('/etc/hosts')
       etc_hosts.block_token = network_name
       etc_hosts.use_private_addresses = network.member?(node)
-      etc_hosts.set_hosts(network.hosts)
+      etc_hosts.set_hosts(network.hosts, alias_mappings)
     end
   end
 end