Add support for Microsoft Azure Linux to Facter 4.x

Add support for Microsoft Azure Linux, prevously known as CBL-Mariner,
Microsoft's Linux distribution for cloud infrastructure and edge products
and services.

lib/facter/config.rb

@@ -26,6 +26,8 @@ module Config
                 Meego
                 Oel
                 Ovs
+                Mariner
+                Azurelinux
               ]
             },
             {
@@ -39,8 +41,7 @@ module Config
             'Photon',
             'Slackware',
             'Mageia',
-            'Openwrt',
-            'Mariner'
+            'Openwrt'
           ]
         },
         {

lib/facter/facts/azurelinux/os/release.rb

@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+module Facts
+  module Azurelinux
+    module Os
+      class Release
+        FACT_NAME = 'os.release'
+        ALIASES = %w[operatingsystemmajrelease operatingsystemrelease].freeze
+
+        def call_the_resolver
+          version = from_specific_file || from_os_release
+
+          return Facter::ResolvedFact.new(FACT_NAME, nil) unless version
+
+          [Facter::ResolvedFact.new(FACT_NAME, version),
+           Facter::ResolvedFact.new(ALIASES.first, version['major'], :legacy),
+           Facter::ResolvedFact.new(ALIASES.last, version['full'], :legacy)]
+        end
+
+        def from_specific_file
+          version = Facter::Resolvers::SpecificReleaseFile.resolve(:release,
+                                                                   { release_file: '/etc/azurelinux-release',
+                                                                     regex: /AZURELINUX_BUILD_NUMBER=([0-9.]+)/ })
+          Facter::Util::Facts.release_hash_from_matchdata(version)
+        end
+
+        def from_os_release
+          version = Facter::Resolvers::OsRelease.resolve(:version_id)
+
+          Facter::Util::Facts.release_hash_from_string(version)
+        end
+      end
+    end
+  end
+end

lib/facter/framework/core/file_loader.rb

@@ -246,6 +246,9 @@
 
     require_relative '../../resolvers/amzn/os_release_rpm'
 
+  when 'azurelinux'
+    require_relative '../../facts/azurelinux/os/release'
+
   when 'bsd'
     require_relative '../../facts/bsd/kernelmajversion'
     require_relative '../../facts/bsd/kernelversion'

lib/facter/resolvers/os_release.rb

@@ -96,6 +96,8 @@ def join_os_name
           @fact_list[:name] = if os_name.downcase.start_with?('red', 'oracle', 'arch', 'manjaro')
                                 os_name = os_name.split(' ')[0..1].join
                                 os_name
+                              elsif os_name.downcase.end_with?('azure linux')
+                                os_name.split(' ')[1..2].join
                               elsif os_name.downcase.end_with?('mariner')
                                 os_name.split(' ')[-1].strip
                               else

lib/facter/util/facts/facts_utils.rb

@@ -10,7 +10,7 @@ module Facts
 
       PHYSICAL_HYPERVISORS = %w[physical xen0 vmware_server vmware_workstation openvzhn vserver_host].freeze
       REDHAT_FAMILY = %w[redhat rhel fedora centos scientific ascendos cloudlinux psbm
-                         oraclelinux ovs oel amazon xenserver xcp-ng virtuozzo photon mariner].freeze
+                         oraclelinux ovs oel amazon xenserver xcp-ng virtuozzo photon mariner azurelinux].freeze
       DEBIAN_FAMILY = %w[debian ubuntu huaweios linuxmint devuan kde].freeze
       SUSE_FAMILY = %w[sles sled suse].freeze
       GENTOO_FAMILY = ['gentoo'].freeze

spec/facter/facts/azurelinux/os/release_spec.rb

@@ -0,0 +1,56 @@
+# frozen_string_literal: true
+
+describe Facts::Azurelinux::Os::Release do
+  describe '#call_the_resolver' do
+    subject(:fact) { Facts::Azurelinux::Os::Release.new }
+
+    before do
+      allow(Facter::Resolvers::SpecificReleaseFile).to receive(:resolve)
+        .with(:release, { release_file: '/etc/azurelinux-release',
+                          regex: /AZURELINUX_BUILD_NUMBER=([0-9.]+)/ })
+        .and_return(value)
+    end
+
+    context 'when version is retrieved from specific file' do
+      let(:value) { /AZURELINUX_BUILD_NUMBER=([0-9.]+)/.match('AZURELINUX_BUILD_NUMBER=3.0.20240401') }
+      let(:release) { { 'full' => '3.0.20240401', 'major' => '3', 'minor' => '0' } }
+
+      it 'returns operating system name fact' do
+        expect(fact.call_the_resolver).to be_an_instance_of(Array).and \
+          contain_exactly(an_object_having_attributes(name: 'os.release', value: release),
+                          an_object_having_attributes(name: 'operatingsystemmajrelease',
+                                                      value: release['major'], type: :legacy),
+                          an_object_having_attributes(name: 'operatingsystemrelease',
+                                                      value: release['full'], type: :legacy))
+      end
+    end
+
+    context 'when version is retrieved from os-release file' do
+      let(:value) { nil }
+      let(:os_release) { '3.0.20240401' }
+      let(:release) { { 'full' => '3.0.20240401', 'major' => '3', 'minor' => '0' } }
+
+      before do
+        allow(Facter::Resolvers::OsRelease).to receive(:resolve).with(:version_id).and_return(os_release)
+      end
+
+      it 'returns operating system name fact' do
+        expect(fact.call_the_resolver).to be_an_instance_of(Array).and \
+          contain_exactly(an_object_having_attributes(name: 'os.release', value: release),
+                          an_object_having_attributes(name: 'operatingsystemmajrelease',
+                                                      value: release['major'], type: :legacy),
+                          an_object_having_attributes(name: 'operatingsystemrelease',
+                                                      value: release['full'], type: :legacy))
+      end
+
+      context 'when release can\'t be received' do
+        let(:os_release) { nil }
+
+        it 'returns operating system name fact' do
+          expect(fact.call_the_resolver).to be_an_instance_of(Facter::ResolvedFact).and \
+            have_attributes(name: 'os.release', value: nil)
+        end
+      end
+    end
+  end
+end