lib/facter/resolvers/partitions.rb
# frozen_string_literal: true
module Facter
module Resolvers
class Partitions < BaseResolver
init_resolver
BLOCK_PATH = '/sys/block'
BLOCK_SIZE = 512
class << self
private
def post_resolve(fact_name, _options)
@fact_list.fetch(fact_name) { read_partitions(fact_name) }
end
def read_partitions(fact_name)
return unless File.readable?(BLOCK_PATH)
block_devices = Dir.entries(BLOCK_PATH).reject { |dir| dir =~ /^\.+/ }
@fact_list[:partitions] = {} unless block_devices.empty?
blkid_and_lsblk = {}
block_devices.each do |block_device|
block_path = "#{BLOCK_PATH}/#{block_device}"
if File.directory?("#{block_path}/device")
extract_from_device(block_path, blkid_and_lsblk)
elsif File.directory?("#{block_path}/dm")
extract_from_dm(block_path, block_device, blkid_and_lsblk)
elsif File.directory?("#{block_path}/loop")
extract_from_loop(block_path, block_device, blkid_and_lsblk)
end
end
@fact_list[fact_name]
end
def extract_from_device(block_path, blkid_and_lsblk)
subdirs = browse_subdirectories(block_path)
subdirs.each do |subdir|
name = "/dev/#{subdir.split('/').last}"
populate_partitions(name, subdir, blkid_and_lsblk)
end
end
def extract_from_dm(block_path, block_device, blkid_and_lsblk)
map_name = Facter::Util::FileHelper.safe_read("#{block_path}/dm/name").chomp
if map_name.empty?
populate_partitions("/dev/#{block_device}", block_path, blkid_and_lsblk)
else
populate_partitions("/dev/mapper/#{map_name}", block_path, blkid_and_lsblk)
end
end
def extract_from_loop(block_path, block_device, blkid_and_lsblk)
backing_file = Facter::Util::FileHelper.safe_read("#{block_path}/loop/backing_file").chomp
if backing_file.empty?
populate_partitions("/dev/#{block_device}", block_path, blkid_and_lsblk)
else
populate_partitions("/dev/#{block_device}", block_path, blkid_and_lsblk, backing_file)
end
end
def populate_partitions(partition_name, block_path, blkid_and_lsblk, backing_file = nil)
size_bytes = Facter::Util::FileHelper.safe_read("#{block_path}/size", '0')
.chomp.to_i * BLOCK_SIZE
info_hash = { size_bytes: size_bytes,
size: Facter::Util::Facts::UnitConverter.bytes_to_human_readable(size_bytes),
backing_file: backing_file }
info_hash.merge!(populate_from_syscalls(partition_name, blkid_and_lsblk))
@fact_list[:partitions][partition_name] = info_hash.reject { |_key, value| value.nil? }
end
def populate_from_syscalls(partition_name, blkid_and_lsblk)
part_info = populate_from_blkid(partition_name, blkid_and_lsblk)
return populate_from_lsblk(partition_name, blkid_and_lsblk) if part_info.empty?
part_info
end
def browse_subdirectories(path)
dirs = Dir[File.join(path, '**', '*')].select { |p| File.directory? p }
dirs.select { |subdir| subdir.split('/').last.include?(path.split('/').last) }.reject(&:nil?)
end
def populate_from_blkid(partition_name, blkid_and_lsblk)
return {} unless available?('blkid', blkid_and_lsblk)
blkid_and_lsblk[:blkid] ||= execute_and_extract_blkid_info
partition_data = blkid_and_lsblk[:blkid][partition_name]
return {} unless partition_data
filesys = partition_data['TYPE']
uuid = partition_data['UUID']
label = partition_data['LABEL']
part_uuid = partition_data['PARTUUID']
part_label = partition_data['PARTLABEL']
{ filesystem: filesys, uuid: uuid, label: label, partuuid: part_uuid, partlabel: part_label }
end
def available?(command, blkid_and_lsblk)
command_exists_key = command == 'blkid' ? :blkid_exists : :lsblk_exists
return blkid_and_lsblk[command_exists_key] unless blkid_and_lsblk[command_exists_key].nil?
blkid_and_lsblk[command_exists_key] = !Facter::Core::Execution.which(command).nil?
end
def execute_and_extract_blkid_info
stdout = Facter::Core::Execution.execute('blkid', logger: log)
output_hash = Hash[*stdout.split(/^([^:]+):/)[1..-1]]
output_hash.each do |key, value|
output_hash[key] = Hash[*value.delete('"').chomp.rstrip.split(/ ([^= ]+)=/)[1..-1]]
end
end
def populate_from_lsblk(partition_name, blkid_and_lsblk)
return {} unless available?('lsblk', blkid_and_lsblk)
blkid_and_lsblk[:lsblk] ||= Facter::Core::Execution.execute('lsblk -fp', logger: log)
part_info = blkid_and_lsblk[:lsblk].match(/#{partition_name}.*/).to_s.split(' ')
return {} if part_info.empty?
parse_part_info(part_info)
end
def parse_part_info(part_info)
result = { filesystem: part_info[1] }
if part_info.count.eql?(5)
result[:label] = part_info[2]
result[:uuid] = part_info[3]
else
result[:uuid] = part_info[2]
end
result
end
end
end
end
end