class UUIDTools::UUID
UUIDTools was designed to be a simple library for generating any of the various types of UUIDs. It conforms to RFC 4122 whenever possible.
@example
UUID.md5_create(UUID_DNS_NAMESPACE, "www.widgets.com") # => #<UUID:0x287576 UUID:3d813cbb-47fb-32ba-91df-831e1593ac29> UUID.sha1_create(UUID_DNS_NAMESPACE, "www.widgets.com") # => #<UUID:0x2a0116 UUID:21f7f8de-8051-5b89-8680-0195ef798b6a> UUID.timestamp_create # => #<UUID:0x2adfdc UUID:64a5189c-25b3-11da-a97b-00c04fd430c8> UUID.random_create # => #<UUID:0x19013a UUID:984265dc-4200-4f02-ae70-fe4f48964159>
Attributes
Returns the value of attribute `clock_seq_hi_and_reserved`
Returns the value of attribute `clock_seq_low`
Returns the value of attribute `nodes`
Returns the value of attribute `time_hi_and_version`
Returns the value of attribute `time_low`
Returns the value of attribute `time_mid`
Public Class Methods
@api private
# File lib/uuidtools.rb, line 709 def self.convert_byte_string_to_int(byte_string) if byte_string.respond_to?(:force_encoding) byte_string.force_encoding(Encoding::ASCII_8BIT) end integer = 0 size = byte_string.size for i in 0..(size - 1) ordinal = (byte_string[i].respond_to?(:ord) ? byte_string[i].ord : byte_string[i]) integer += (ordinal << (((size - 1) - i) * 8)) end return integer end
@api private
# File lib/uuidtools.rb, line 696 def self.convert_int_to_byte_string(integer, size) byte_string = "" if byte_string.respond_to?(:force_encoding) byte_string.force_encoding(Encoding::ASCII_8BIT) end for i in 0..(size - 1) byte_string << ((integer >> (((size - 1) - i) * 8)) & 0xFF) end return byte_string end
Creates a new UUID from a SHA1 or MD5 hash
@api private
# File lib/uuidtools.rb, line 671 def self.create_from_hash(hash_class, namespace, name) if hash_class == Digest::MD5 version = 3 elsif hash_class == Digest::SHA1 version = 5 else raise ArgumentError, "Expected Digest::SHA1 or Digest::MD5, got #{hash_class.name}." end hash = hash_class.new hash.update(namespace.raw) hash.update(name) hash_string = hash.to_s[0..31] new_uuid = self.parse("#{hash_string[0..7]}-#{hash_string[8..11]}-" + "#{hash_string[12..15]}-#{hash_string[16..19]}-#{hash_string[20..31]}") new_uuid.time_hi_and_version &= 0x0FFF new_uuid.time_hi_and_version |= (version << 12) new_uuid.clock_seq_hi_and_reserved &= 0x3F new_uuid.clock_seq_hi_and_reserved |= 0x80 return new_uuid end
Match and return the first Mac address found
# File lib/uuidtools.rb, line 590 def self.first_mac(instring) mac_regexps = [ Regexp.new("address:? (#{(["[0-9a-fA-F]{2}"] * 6).join(":")})"), Regexp.new("addr:? (#{(["[0-9a-fA-F]{2}"] * 6).join(":")})"), Regexp.new("ether:? (#{(["[0-9a-fA-F]{1,2}"] * 6).join(":")})"), Regexp.new("HWaddr:? (#{(["[0-9a-fA-F]{2}"] * 6).join(":")})"), Regexp.new("link/ether? (#{(["[0-9a-fA-F]{2}"] * 6).join(":")})"), Regexp.new("(#{(["[0-9a-fA-F]{2}"] * 6).join(":")})"), Regexp.new("(#{(["[0-9a-fA-F]{2}"] * 6).join("-")})") ] parse_mac = lambda do |output| (mac_regexps.map do |regexp| result = output[regexp, 1] result.downcase.gsub(/-/, ":") if result != nil end).compact.first end mac = parse_mac.call(instring) if mac # expand octets that were compressed (solaris) return (mac.split(':').map do |octet| (octet.length == 1 ? "0#{octet}" : octet) end).join(':') else return nil end end
Call the ifconfig or ip command that is found
# File lib/uuidtools.rb, line 574 def self.ifconfig(all=nil) # find the path of the ifconfig command ifconfig_path = UUID.ifconfig_path # if it does not exist, try the ip command if ifconfig_path == nil ifconfig_path = "#{UUID.ip_path} addr list" # all makes no sense when using ip(1) all = nil end all_switch = all == nil ? "" : "-a" return %x`#{ifconfig_path} #{all_switch}` if not ifconfig_path == nil end
Find the path of the ifconfig(8) command if it is present
# File lib/uuidtools.rb, line 556 def self.ifconfig_path path = %x`which #{UUID.ifconfig_command} 2>/dev/null`.strip path = UUID.ifconfig_path_default if (path == "" && File.exist?(UUID.ifconfig_path_default)) return (path === "" ? nil : path) end
Find the path of the ip(8) command if it is present
# File lib/uuidtools.rb, line 565 def self.ip_path path = %x`which #{UUID.ip_command} 2>/dev/null`.strip path = UUID.ip_path_default if (path == "" && File.exist?(UUID.ip_path_default)) return (path === "" ? nil : path) end
Returns the MAC address of the current computer's network card. Returns nil if a MAC address could not be found.
# File lib/uuidtools.rb, line 621 def self.mac_address if !defined?(@@mac_address) require 'rbconfig' os_class = UUID.os_class if os_class == :windows begin @@mac_address = UUID.first_mac %x`ipconfig /all` rescue end else # linux, bsd, macos, solaris @@mac_address = UUID.first_mac(UUID.ifconfig(:all)) end if @@mac_address != nil if @@mac_address.respond_to?(:to_str) @@mac_address = @@mac_address.to_str else @@mac_address = @@mac_address.to_s end @@mac_address.downcase! @@mac_address.strip! end # Verify that the MAC address is in the right format. # Nil it out if it isn't. unless @@mac_address.respond_to?(:scan) && @@mac_address.scan(/#{(["[0-9a-f]{2}"] * 6).join(":")}/) @@mac_address = nil end end return @@mac_address end
Allows users to set the MAC address manually in cases where the MAC address cannot be obtained programatically.
# File lib/uuidtools.rb, line 659 def self.mac_address=(new_mac_address) @@mac_address = new_mac_address end
Creates a UUID using the MD5 hash. (Version 3)
# File lib/uuidtools.rb, line 288 def self.md5_create(namespace, name) return self.create_from_hash(Digest::MD5, namespace, name) end
Creates a new UUID structure from its component values. @see ::md5_create @see ::sha1_create @see ::timestamp_create @see ::random_create @api private
# File lib/uuidtools.rb, line 79 def initialize(time_low, time_mid, time_hi_and_version, clock_seq_hi_and_reserved, clock_seq_low, nodes) unless time_low >= 0 && time_low < 4294967296 raise ArgumentError, "Expected unsigned 32-bit number for time_low, got #{time_low}." end unless time_mid >= 0 && time_mid < 65536 raise ArgumentError, "Expected unsigned 16-bit number for time_mid, got #{time_mid}." end unless time_hi_and_version >= 0 && time_hi_and_version < 65536 raise ArgumentError, "Expected unsigned 16-bit number for time_hi_and_version, " + "got #{time_hi_and_version}." end unless clock_seq_hi_and_reserved >= 0 && clock_seq_hi_and_reserved < 256 raise ArgumentError, "Expected unsigned 8-bit number for clock_seq_hi_and_reserved, " + "got #{clock_seq_hi_and_reserved}." end unless clock_seq_low >= 0 && clock_seq_low < 256 raise ArgumentError, "Expected unsigned 8-bit number for clock_seq_low, " + "got #{clock_seq_low}." end unless nodes.kind_of?(Enumerable) raise TypeError, "Expected Enumerable, got #{nodes.class.name}." end unless nodes.size == 6 raise ArgumentError, "Expected nodes to have size of 6." end for node in nodes unless node >= 0 && node < 256 raise ArgumentError, "Expected unsigned 8-bit number for each node, " + "got #{node}." end end @time_low = time_low @time_mid = time_mid @time_hi_and_version = time_hi_and_version @clock_seq_hi_and_reserved = clock_seq_hi_and_reserved @clock_seq_low = clock_seq_low @nodes = nodes end
Determine what OS we're running on. Helps decide how to find the MAC
# File lib/uuidtools.rb, line 526 def self.os_class require 'rbconfig' os_platform = RbConfig::CONFIG['target_os'] os_class = nil if (os_platform =~ /win/i && !(os_platform =~ /darwin/i)) || os_platform =~ /w32/i os_class = :windows elsif os_platform =~ /solaris/i os_class = :solaris elsif os_platform =~ /netbsd/i os_class = :netbsd elsif os_platform =~ /openbsd/i os_class = :openbsd end end
Parses a UUID from a string.
# File lib/uuidtools.rb, line 153 def self.parse(uuid_string) unless uuid_string.kind_of? String raise TypeError, "Expected String, got #{uuid_string.class.name} instead." end uuid_components = uuid_string.downcase.scan(UUIDTools::UUID_REGEXP).first raise ArgumentError, "Invalid UUID format." if uuid_components.nil? time_low = uuid_components[0].to_i(16) time_mid = uuid_components[1].to_i(16) time_hi_and_version = uuid_components[2].to_i(16) clock_seq_hi_and_reserved = uuid_components[3].to_i(16) clock_seq_low = uuid_components[4].to_i(16) nodes = [] for i in 0..5 nodes << uuid_components[5][(i * 2)..(i * 2) + 1].to_i(16) end return self.new(time_low, time_mid, time_hi_and_version, clock_seq_hi_and_reserved, clock_seq_low, nodes) end
Parse a UUID from a hexdigest String.
# File lib/uuidtools.rb, line 207 def self.parse_hexdigest(uuid_hexdigest) unless uuid_hexdigest.kind_of?(String) raise ArgumentError, "Expected String, got #{uuid_hexdigest.class.name} instead." end return self.parse_int(uuid_hexdigest.to_i(16)) end
Parses a UUID from an Integer.
# File lib/uuidtools.rb, line 197 def self.parse_int(uuid_int) unless uuid_int.kind_of?(Integer) raise ArgumentError, "Expected Integer, got #{uuid_int.class.name} instead." end return self.parse_raw(self.convert_int_to_byte_string(uuid_int, 16)) end
Parses a UUID from a raw byte string.
# File lib/uuidtools.rb, line 175 def self.parse_raw(raw_string) unless raw_string.kind_of? String raise TypeError, "Expected String, got #{raw_string.class.name} instead." end integer = self.convert_byte_string_to_int(raw_string) time_low = (integer >> 96) & 0xFFFFFFFF time_mid = (integer >> 80) & 0xFFFF time_hi_and_version = (integer >> 64) & 0xFFFF clock_seq_hi_and_reserved = (integer >> 56) & 0xFF clock_seq_low = (integer >> 48) & 0xFF nodes = [] for i in 0..5 nodes << ((integer >> (40 - (i * 8))) & 0xFF) end return self.new(time_low, time_mid, time_hi_and_version, clock_seq_hi_and_reserved, clock_seq_low, nodes) end
Creates a UUID from a random value.
# File lib/uuidtools.rb, line 217 def self.random_create() new_uuid = self.parse_raw(SecureRandom.random_bytes(16)) new_uuid.time_hi_and_version &= 0x0FFF new_uuid.time_hi_and_version |= (4 << 12) new_uuid.clock_seq_hi_and_reserved &= 0x3F new_uuid.clock_seq_hi_and_reserved |= 0x80 return new_uuid end
Creates a UUID using the SHA1 hash. (Version 5)
# File lib/uuidtools.rb, line 294 def self.sha1_create(namespace, name) return self.create_from_hash(Digest::SHA1, namespace, name) end
Creates a UUID from a timestamp.
# File lib/uuidtools.rb, line 228 def self.timestamp_create(timestamp=nil) # We need a lock here to prevent two threads from ever # getting the same timestamp. @@mutex.synchronize do # Always use GMT to generate UUIDs. if timestamp.nil? gmt_timestamp = Time.now.gmtime else gmt_timestamp = timestamp.gmtime end # Convert to 100 nanosecond blocks gmt_timestamp_100_nanoseconds = (gmt_timestamp.tv_sec * 10000000) + (gmt_timestamp.tv_usec * 10) + 0x01B21DD213814000 mac_address = self.mac_address node_id = 0 if mac_address != nil nodes = mac_address.split(":").collect do |octet| octet.to_i(16) end else nodes = SecureRandom.random_bytes(6).unpack("C*") nodes[0] |= 0b00000001 end for i in 0..5 node_id += (nodes[i] << (40 - (i * 8))) end clock_sequence = @@last_clock_sequence if clock_sequence.nil? clock_sequence = self.convert_byte_string_to_int( SecureRandom.random_bytes(16) ) end if @@last_node_id != nil && @@last_node_id != node_id # The node id has changed. Change the clock id. clock_sequence = self.convert_byte_string_to_int( SecureRandom.random_bytes(16) ) elsif @@last_timestamp != nil && gmt_timestamp_100_nanoseconds <= @@last_timestamp clock_sequence = clock_sequence + 1 end @@last_timestamp = gmt_timestamp_100_nanoseconds @@last_node_id = node_id @@last_clock_sequence = clock_sequence time_low = gmt_timestamp_100_nanoseconds & 0xFFFFFFFF time_mid = ((gmt_timestamp_100_nanoseconds >> 32) & 0xFFFF) time_hi_and_version = ((gmt_timestamp_100_nanoseconds >> 48) & 0x0FFF) time_hi_and_version |= (1 << 12) clock_seq_low = clock_sequence & 0xFF; clock_seq_hi_and_reserved = (clock_sequence & 0x3F00) >> 8 clock_seq_hi_and_reserved |= 0x80 return self.new(time_low, time_mid, time_hi_and_version, clock_seq_hi_and_reserved, clock_seq_low, nodes) end end
Public Instance Methods
Compares two UUIDs lexically
# File lib/uuidtools.rb, line 394 def <=>(other_uuid) return nil unless other_uuid.is_a?(UUIDTools::UUID) check = self.time_low <=> other_uuid.time_low return check if check != 0 check = self.time_mid <=> other_uuid.time_mid return check if check != 0 check = self.time_hi_and_version <=> other_uuid.time_hi_and_version return check if check != 0 check = self.clock_seq_hi_and_reserved <=> other_uuid.clock_seq_hi_and_reserved return check if check != 0 check = self.clock_seq_low <=> other_uuid.clock_seq_low return check if check != 0 for i in 0..5 if (self.nodes[i] < other_uuid.nodes[i]) return -1 end if (self.nodes[i] > other_uuid.nodes[i]) return 1 end end return 0 end
Returns an integer hash value.
# File lib/uuidtools.rb, line 459 def hash self.frozen? ? generate_hash : (@hash ||= generate_hash) end
Returns the hex digest of the UUID object.
# File lib/uuidtools.rb, line 426 def hexdigest (self.frozen? ? generate_hexdigest : (@hexdigest ||= generate_hexdigest) ).dup end
Returns a representation of the object's state
# File lib/uuidtools.rb, line 420 def inspect return "#<UUID:0x#{self.object_id.to_s(16)} UUID:#{self.to_s}>" end
Returns the IEEE 802 address used to generate this UUID or nil if a MAC address was not used.
# File lib/uuidtools.rb, line 371 def mac_address return nil if self.version != 1 return nil if self.random_node_id? return (self.nodes.collect do |node| sprintf("%2.2x", node) end).join(":") end
Returns true if this UUID is the nil UUID (00000000-0000-0000-0000-000000000000).
# File lib/uuidtools.rb, line 313 def nil_uuid? return false if self.time_low != 0 return false if self.time_mid != 0 return false if self.time_hi_and_version != 0 return false if self.clock_seq_hi_and_reserved != 0 return false if self.clock_seq_low != 0 self.nodes.each do |node| return false if node != 0 end return true end
This method applies only to version 1 UUIDs. Checks if the node ID was generated from a random number or from an IEEE 802 address (MAC address). Always returns false for UUIDs that aren't version 1. This should not be confused with version 4 UUIDs where more than just the node id is random.
# File lib/uuidtools.rb, line 305 def random_node_id? return false if self.version != 1 return ((self.nodes.first & 0x01) == 1) end
Returns the raw bytes that represent this UUID.
# File lib/uuidtools.rb, line 434 def raw (self.frozen? ? generate_raw : (@raw ||= generate_raw)).dup end
Returns the timestamp used to generate this UUID
# File lib/uuidtools.rb, line 381 def timestamp return nil if self.version != 1 gmt_timestamp_100_nanoseconds = 0 gmt_timestamp_100_nanoseconds += ((self.time_hi_and_version & 0x0FFF) << 48) gmt_timestamp_100_nanoseconds += (self.time_mid << 32) gmt_timestamp_100_nanoseconds += self.time_low return Time.at( (gmt_timestamp_100_nanoseconds - 0x01B21DD213814000) / 10000000.0) end
Returns an integer representation for this UUID.
# File lib/uuidtools.rb, line 447 def to_i self.frozen? ? generate_i : (@integer ||= generate_i) end
Returns a string representation for this UUID.
# File lib/uuidtools.rb, line 440 def to_s (self.frozen? ? generate_s : (@string ||= generate_s)).dup end
Returns a URI string for this UUID.
# File lib/uuidtools.rb, line 453 def to_uri return "urn:uuid:#{self.to_s}" end
Returns true if this UUID is valid.
# File lib/uuidtools.rb, line 359 def valid? if [0b000, 0b100, 0b110, 0b111].include?(self.variant) && (1..5).include?(self.version) return true else return false end end
Returns the UUID variant. Possible values: 0b000 - Reserved, NCS backward compatibility. 0b100 - The variant specified in this document. 0b110 - Reserved, Microsoft Corporation backward compatibility. 0b111 - Reserved for future definition.
# File lib/uuidtools.rb, line 344 def variant variant_raw = (clock_seq_hi_and_reserved >> 5) result = nil if (variant_raw >> 2) == 0 result = 0x000 elsif (variant_raw >> 1) == 2 result = 0x100 else result = variant_raw end return (result >> 6) end
Returns the UUID version type. Possible values: 1 - Time-based with unique or random host identifier 2 - DCE Security version (with POSIX UIDs) 3 - Name-based (MD5 hash) 4 - Random 5 - Name-based (SHA-1 hash)
# File lib/uuidtools.rb, line 333 def version return (time_hi_and_version >> 12) end
Protected Instance Methods
Generates an integer hash value.
@api private
# File lib/uuidtools.rb, line 475 def generate_hash return self.to_i % 0x3fffffff end
Generates the hex digest of the UUID object.
@api private
# File lib/uuidtools.rb, line 468 def generate_hexdigest return self.to_i.to_s(16).rjust(32, "0") end
Generates an integer representation for this UUID.
@api private
# File lib/uuidtools.rb, line 483 def generate_i return (begin bytes = (time_low << 96) + (time_mid << 80) + (time_hi_and_version << 64) + (clock_seq_hi_and_reserved << 56) + (clock_seq_low << 48) for i in 0..5 bytes += (nodes[i] << (40 - (i * 8))) end bytes end) end
Generates the raw bytes that represent this UUID.
@api private
# File lib/uuidtools.rb, line 512 def generate_raw return self.class.convert_int_to_byte_string(self.to_i, 16) end
Generates a string representation for this UUID.
@api private
# File lib/uuidtools.rb, line 499 def generate_s result = sprintf("%8.8x-%4.4x-%4.4x-%2.2x%2.2x-", @time_low, @time_mid, @time_hi_and_version, @clock_seq_hi_and_reserved, @clock_seq_low); for i in 0..5 result << sprintf("%2.2x", @nodes[i]) end return result.downcase end