| r"""UUID objects (universally unique identifiers) according to RFC 4122. |
| |
| This module provides immutable UUID objects (class UUID) and the functions |
| uuid1(), uuid3(), uuid4(), uuid5() for generating version 1, 3, 4, and 5 |
| UUIDs as specified in RFC 4122. |
| |
| If all you want is a unique ID, you should probably call uuid1() or uuid4(). |
| Note that uuid1() may compromise privacy since it creates a UUID containing |
| the computer's network address. uuid4() creates a random UUID. |
| |
| Typical usage: |
| |
| >>> import uuid |
| |
| # make a UUID based on the host ID and current time |
| >>> uuid.uuid1() # doctest: +SKIP |
| UUID('a8098c1a-f86e-11da-bd1a-00112444be1e') |
| |
| # make a UUID using an MD5 hash of a namespace UUID and a name |
| >>> uuid.uuid3(uuid.NAMESPACE_DNS, 'python.org') |
| UUID('6fa459ea-ee8a-3ca4-894e-db77e160355e') |
| |
| # make a random UUID |
| >>> uuid.uuid4() # doctest: +SKIP |
| UUID('16fd2706-8baf-433b-82eb-8c7fada847da') |
| |
| # make a UUID using a SHA-1 hash of a namespace UUID and a name |
| >>> uuid.uuid5(uuid.NAMESPACE_DNS, 'python.org') |
| UUID('886313e1-3b8a-5372-9b90-0c9aee199e5d') |
| |
| # make a UUID from a string of hex digits (braces and hyphens ignored) |
| >>> x = uuid.UUID('{00010203-0405-0607-0809-0a0b0c0d0e0f}') |
| |
| # convert a UUID to a string of hex digits in standard form |
| >>> str(x) |
| '00010203-0405-0607-0809-0a0b0c0d0e0f' |
| |
| # get the raw 16 bytes of the UUID |
| >>> x.bytes |
| b'\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f' |
| |
| # make a UUID from a 16-byte string |
| >>> uuid.UUID(bytes=x.bytes) |
| UUID('00010203-0405-0607-0809-0a0b0c0d0e0f') |
| """ |
| |
| __author__ = 'Ka-Ping Yee <ping@zesty.ca>' |
| |
| RESERVED_NCS, RFC_4122, RESERVED_MICROSOFT, RESERVED_FUTURE = [ |
| 'reserved for NCS compatibility', 'specified in RFC 4122', |
| 'reserved for Microsoft compatibility', 'reserved for future definition'] |
| |
| int_ = int # The built-in int type |
| bytes_ = bytes # The built-in bytes type |
| |
| class UUID(object): |
| """Instances of the UUID class represent UUIDs as specified in RFC 4122. |
| UUID objects are immutable, hashable, and usable as dictionary keys. |
| Converting a UUID to a string with str() yields something in the form |
| '12345678-1234-1234-1234-123456789abc'. The UUID constructor accepts |
| five possible forms: a similar string of hexadecimal digits, or a tuple |
| of six integer fields (with 32-bit, 16-bit, 16-bit, 8-bit, 8-bit, and |
| 48-bit values respectively) as an argument named 'fields', or a string |
| of 16 bytes (with all the integer fields in big-endian order) as an |
| argument named 'bytes', or a string of 16 bytes (with the first three |
| fields in little-endian order) as an argument named 'bytes_le', or a |
| single 128-bit integer as an argument named 'int'. |
| |
| UUIDs have these read-only attributes: |
| |
| bytes the UUID as a 16-byte string (containing the six |
| integer fields in big-endian byte order) |
| |
| bytes_le the UUID as a 16-byte string (with time_low, time_mid, |
| and time_hi_version in little-endian byte order) |
| |
| fields a tuple of the six integer fields of the UUID, |
| which are also available as six individual attributes |
| and two derived attributes: |
| |
| time_low the first 32 bits of the UUID |
| time_mid the next 16 bits of the UUID |
| time_hi_version the next 16 bits of the UUID |
| clock_seq_hi_variant the next 8 bits of the UUID |
| clock_seq_low the next 8 bits of the UUID |
| node the last 48 bits of the UUID |
| |
| time the 60-bit timestamp |
| clock_seq the 14-bit sequence number |
| |
| hex the UUID as a 32-character hexadecimal string |
| |
| int the UUID as a 128-bit integer |
| |
| urn the UUID as a URN as specified in RFC 4122 |
| |
| variant the UUID variant (one of the constants RESERVED_NCS, |
| RFC_4122, RESERVED_MICROSOFT, or RESERVED_FUTURE) |
| |
| version the UUID version number (1 through 5, meaningful only |
| when the variant is RFC_4122) |
| """ |
| |
| def __init__(self, hex=None, bytes=None, bytes_le=None, fields=None, |
| int=None, version=None): |
| r"""Create a UUID from either a string of 32 hexadecimal digits, |
| a string of 16 bytes as the 'bytes' argument, a string of 16 bytes |
| in little-endian order as the 'bytes_le' argument, a tuple of six |
| integers (32-bit time_low, 16-bit time_mid, 16-bit time_hi_version, |
| 8-bit clock_seq_hi_variant, 8-bit clock_seq_low, 48-bit node) as |
| the 'fields' argument, or a single 128-bit integer as the 'int' |
| argument. When a string of hex digits is given, curly braces, |
| hyphens, and a URN prefix are all optional. For example, these |
| expressions all yield the same UUID: |
| |
| UUID('{12345678-1234-5678-1234-567812345678}') |
| UUID('12345678123456781234567812345678') |
| UUID('urn:uuid:12345678-1234-5678-1234-567812345678') |
| UUID(bytes='\x12\x34\x56\x78'*4) |
| UUID(bytes_le='\x78\x56\x34\x12\x34\x12\x78\x56' + |
| '\x12\x34\x56\x78\x12\x34\x56\x78') |
| UUID(fields=(0x12345678, 0x1234, 0x5678, 0x12, 0x34, 0x567812345678)) |
| UUID(int=0x12345678123456781234567812345678) |
| |
| Exactly one of 'hex', 'bytes', 'bytes_le', 'fields', or 'int' must |
| be given. The 'version' argument is optional; if given, the resulting |
| UUID will have its variant and version set according to RFC 4122, |
| overriding the given 'hex', 'bytes', 'bytes_le', 'fields', or 'int'. |
| """ |
| |
| if [hex, bytes, bytes_le, fields, int].count(None) != 4: |
| raise TypeError('need one of hex, bytes, bytes_le, fields, or int') |
| if hex is not None: |
| hex = hex.replace('urn:', '').replace('uuid:', '') |
| hex = hex.strip('{}').replace('-', '') |
| if len(hex) != 32: |
| raise ValueError('badly formed hexadecimal UUID string') |
| int = int_(hex, 16) |
| if bytes_le is not None: |
| if len(bytes_le) != 16: |
| raise ValueError('bytes_le is not a 16-char string') |
| bytes = (bytes_(reversed(bytes_le[0:4])) + |
| bytes_(reversed(bytes_le[4:6])) + |
| bytes_(reversed(bytes_le[6:8])) + |
| bytes_le[8:]) |
| if bytes is not None: |
| if len(bytes) != 16: |
| raise ValueError('bytes is not a 16-char string') |
| assert isinstance(bytes, bytes_), repr(bytes) |
| int = int_(('%02x'*16) % tuple(bytes), 16) |
| if fields is not None: |
| if len(fields) != 6: |
| raise ValueError('fields is not a 6-tuple') |
| (time_low, time_mid, time_hi_version, |
| clock_seq_hi_variant, clock_seq_low, node) = fields |
| if not 0 <= time_low < 1<<32: |
| raise ValueError('field 1 out of range (need a 32-bit value)') |
| if not 0 <= time_mid < 1<<16: |
| raise ValueError('field 2 out of range (need a 16-bit value)') |
| if not 0 <= time_hi_version < 1<<16: |
| raise ValueError('field 3 out of range (need a 16-bit value)') |
| if not 0 <= clock_seq_hi_variant < 1<<8: |
| raise ValueError('field 4 out of range (need an 8-bit value)') |
| if not 0 <= clock_seq_low < 1<<8: |
| raise ValueError('field 5 out of range (need an 8-bit value)') |
| if not 0 <= node < 1<<48: |
| raise ValueError('field 6 out of range (need a 48-bit value)') |
| clock_seq = (clock_seq_hi_variant << 8) | clock_seq_low |
| int = ((time_low << 96) | (time_mid << 80) | |
| (time_hi_version << 64) | (clock_seq << 48) | node) |
| if int is not None: |
| if not 0 <= int < 1<<128: |
| raise ValueError('int is out of range (need a 128-bit value)') |
| if version is not None: |
| if not 1 <= version <= 5: |
| raise ValueError('illegal version number') |
| # Set the variant to RFC 4122. |
| int &= ~(0xc000 << 48) |
| int |= 0x8000 << 48 |
| # Set the version number. |
| int &= ~(0xf000 << 64) |
| int |= version << 76 |
| self.__dict__['int'] = int |
| |
| def __eq__(self, other): |
| if isinstance(other, UUID): |
| return self.int == other.int |
| return NotImplemented |
| |
| def __ne__(self, other): |
| if isinstance(other, UUID): |
| return self.int != other.int |
| return NotImplemented |
| |
| # Q. What's the value of being able to sort UUIDs? |
| # A. Use them as keys in a B-Tree or similar mapping. |
| |
| def __lt__(self, other): |
| if isinstance(other, UUID): |
| return self.int < other.int |
| return NotImplemented |
| |
| def __gt__(self, other): |
| if isinstance(other, UUID): |
| return self.int > other.int |
| return NotImplemented |
| |
| def __le__(self, other): |
| if isinstance(other, UUID): |
| return self.int <= other.int |
| return NotImplemented |
| |
| def __ge__(self, other): |
| if isinstance(other, UUID): |
| return self.int >= other.int |
| return NotImplemented |
| |
| def __hash__(self): |
| return hash(self.int) |
| |
| def __int__(self): |
| return self.int |
| |
| def __repr__(self): |
| return 'UUID(%r)' % str(self) |
| |
| def __setattr__(self, name, value): |
| raise TypeError('UUID objects are immutable') |
| |
| def __str__(self): |
| hex = '%032x' % self.int |
| return '%s-%s-%s-%s-%s' % ( |
| hex[:8], hex[8:12], hex[12:16], hex[16:20], hex[20:]) |
| |
| @property |
| def bytes(self): |
| bytes = bytearray() |
| for shift in range(0, 128, 8): |
| bytes.insert(0, (self.int >> shift) & 0xff) |
| return bytes_(bytes) |
| |
| @property |
| def bytes_le(self): |
| bytes = self.bytes |
| return (bytes_(reversed(bytes[0:4])) + |
| bytes_(reversed(bytes[4:6])) + |
| bytes_(reversed(bytes[6:8])) + |
| bytes[8:]) |
| |
| @property |
| def fields(self): |
| return (self.time_low, self.time_mid, self.time_hi_version, |
| self.clock_seq_hi_variant, self.clock_seq_low, self.node) |
| |
| @property |
| def time_low(self): |
| return self.int >> 96 |
| |
| @property |
| def time_mid(self): |
| return (self.int >> 80) & 0xffff |
| |
| @property |
| def time_hi_version(self): |
| return (self.int >> 64) & 0xffff |
| |
| @property |
| def clock_seq_hi_variant(self): |
| return (self.int >> 56) & 0xff |
| |
| @property |
| def clock_seq_low(self): |
| return (self.int >> 48) & 0xff |
| |
| @property |
| def time(self): |
| return (((self.time_hi_version & 0x0fff) << 48) | |
| (self.time_mid << 32) | self.time_low) |
| |
| @property |
| def clock_seq(self): |
| return (((self.clock_seq_hi_variant & 0x3f) << 8) | |
| self.clock_seq_low) |
| |
| @property |
| def node(self): |
| return self.int & 0xffffffffffff |
| |
| @property |
| def hex(self): |
| return '%032x' % self.int |
| |
| @property |
| def urn(self): |
| return 'urn:uuid:' + str(self) |
| |
| @property |
| def variant(self): |
| if not self.int & (0x8000 << 48): |
| return RESERVED_NCS |
| elif not self.int & (0x4000 << 48): |
| return RFC_4122 |
| elif not self.int & (0x2000 << 48): |
| return RESERVED_MICROSOFT |
| else: |
| return RESERVED_FUTURE |
| |
| @property |
| def version(self): |
| # The version bits are only meaningful for RFC 4122 UUIDs. |
| if self.variant == RFC_4122: |
| return int((self.int >> 76) & 0xf) |
| |
| def _find_mac(command, args, hw_identifiers, get_index): |
| import os |
| for dir in ['', '/sbin/', '/usr/sbin']: |
| executable = os.path.join(dir, command) |
| if not os.path.exists(executable): |
| continue |
| |
| try: |
| # LC_ALL to get English output, 2>/dev/null to |
| # prevent output on stderr |
| cmd = 'LC_ALL=C %s %s 2>/dev/null' % (executable, args) |
| with os.popen(cmd) as pipe: |
| for line in pipe: |
| words = line.lower().split() |
| for i in range(len(words)): |
| if words[i] in hw_identifiers: |
| return int( |
| words[get_index(i)].replace(':', ''), 16) |
| except IOError: |
| continue |
| return None |
| |
| def _ifconfig_getnode(): |
| """Get the hardware address on Unix by running ifconfig.""" |
| |
| # This works on Linux ('' or '-a'), Tru64 ('-av'), but not all Unixes. |
| for args in ('', '-a', '-av'): |
| mac = _find_mac('ifconfig', args, ['hwaddr', 'ether'], lambda i: i+1) |
| if mac: |
| return mac |
| |
| import socket |
| ip_addr = socket.gethostbyname(socket.gethostname()) |
| |
| # Try getting the MAC addr from arp based on our IP address (Solaris). |
| mac = _find_mac('arp', '-an', [ip_addr], lambda i: -1) |
| if mac: |
| return mac |
| |
| # This might work on HP-UX. |
| mac = _find_mac('lanscan', '-ai', ['lan0'], lambda i: 0) |
| if mac: |
| return mac |
| |
| return None |
| |
| def _ipconfig_getnode(): |
| """Get the hardware address on Windows by running ipconfig.exe.""" |
| import os, re |
| dirs = ['', r'c:\windows\system32', r'c:\winnt\system32'] |
| try: |
| import ctypes |
| buffer = ctypes.create_string_buffer(300) |
| ctypes.windll.kernel32.GetSystemDirectoryA(buffer, 300) |
| dirs.insert(0, buffer.value.decode('mbcs')) |
| except: |
| pass |
| for dir in dirs: |
| try: |
| pipe = os.popen(os.path.join(dir, 'ipconfig') + ' /all') |
| except IOError: |
| continue |
| else: |
| for line in pipe: |
| value = line.split(':')[-1].strip().lower() |
| if re.match('([0-9a-f][0-9a-f]-){5}[0-9a-f][0-9a-f]', value): |
| return int(value.replace('-', ''), 16) |
| finally: |
| pipe.close() |
| |
| def _netbios_getnode(): |
| """Get the hardware address on Windows using NetBIOS calls. |
| See http://support.microsoft.com/kb/118623 for details.""" |
| import win32wnet, netbios |
| ncb = netbios.NCB() |
| ncb.Command = netbios.NCBENUM |
| ncb.Buffer = adapters = netbios.LANA_ENUM() |
| adapters._pack() |
| if win32wnet.Netbios(ncb) != 0: |
| return |
| adapters._unpack() |
| for i in range(adapters.length): |
| ncb.Reset() |
| ncb.Command = netbios.NCBRESET |
| ncb.Lana_num = ord(adapters.lana[i]) |
| if win32wnet.Netbios(ncb) != 0: |
| continue |
| ncb.Reset() |
| ncb.Command = netbios.NCBASTAT |
| ncb.Lana_num = ord(adapters.lana[i]) |
| ncb.Callname = '*'.ljust(16) |
| ncb.Buffer = status = netbios.ADAPTER_STATUS() |
| if win32wnet.Netbios(ncb) != 0: |
| continue |
| status._unpack() |
| bytes = status.adapter_address |
| return ((bytes[0]<<40) + (bytes[1]<<32) + (bytes[2]<<24) + |
| (bytes[3]<<16) + (bytes[4]<<8) + bytes[5]) |
| |
| # Thanks to Thomas Heller for ctypes and for his help with its use here. |
| |
| # If ctypes is available, use it to find system routines for UUID generation. |
| # XXX This makes the module non-thread-safe! |
| _uuid_generate_random = _uuid_generate_time = _UuidCreate = None |
| try: |
| import ctypes, ctypes.util |
| |
| # The uuid_generate_* routines are provided by libuuid on at least |
| # Linux and FreeBSD, and provided by libc on Mac OS X. |
| for libname in ['uuid', 'c']: |
| try: |
| lib = ctypes.CDLL(ctypes.util.find_library(libname)) |
| except: |
| continue |
| if hasattr(lib, 'uuid_generate_random'): |
| _uuid_generate_random = lib.uuid_generate_random |
| if hasattr(lib, 'uuid_generate_time'): |
| _uuid_generate_time = lib.uuid_generate_time |
| if _uuid_generate_random is not None: |
| break # found everything we were looking for |
| |
| # The uuid_generate_* functions are broken on MacOS X 10.5, as noted |
| # in issue #8621 the function generates the same sequence of values |
| # in the parent process and all children created using fork (unless |
| # those children use exec as well). |
| # |
| # Assume that the uuid_generate functions are broken from 10.5 onward, |
| # the test can be adjusted when a later version is fixed. |
| import sys |
| if sys.platform == 'darwin': |
| import os |
| if int(os.uname().release.split('.')[0]) >= 9: |
| _uuid_generate_random = _uuid_generate_time = None |
| |
| # On Windows prior to 2000, UuidCreate gives a UUID containing the |
| # hardware address. On Windows 2000 and later, UuidCreate makes a |
| # random UUID and UuidCreateSequential gives a UUID containing the |
| # hardware address. These routines are provided by the RPC runtime. |
| # NOTE: at least on Tim's WinXP Pro SP2 desktop box, while the last |
| # 6 bytes returned by UuidCreateSequential are fixed, they don't appear |
| # to bear any relationship to the MAC address of any network device |
| # on the box. |
| try: |
| lib = ctypes.windll.rpcrt4 |
| except: |
| lib = None |
| _UuidCreate = getattr(lib, 'UuidCreateSequential', |
| getattr(lib, 'UuidCreate', None)) |
| except: |
| pass |
| |
| def _unixdll_getnode(): |
| """Get the hardware address on Unix using ctypes.""" |
| _buffer = ctypes.create_string_buffer(16) |
| _uuid_generate_time(_buffer) |
| return UUID(bytes=bytes_(_buffer.raw)).node |
| |
| def _windll_getnode(): |
| """Get the hardware address on Windows using ctypes.""" |
| _buffer = ctypes.create_string_buffer(16) |
| if _UuidCreate(_buffer) == 0: |
| return UUID(bytes=bytes_(_buffer.raw)).node |
| |
| def _random_getnode(): |
| """Get a random node ID, with eighth bit set as suggested by RFC 4122.""" |
| import random |
| return random.randrange(0, 1<<48) | 0x010000000000 |
| |
| _node = None |
| |
| def getnode(): |
| """Get the hardware address as a 48-bit positive integer. |
| |
| The first time this runs, it may launch a separate program, which could |
| be quite slow. If all attempts to obtain the hardware address fail, we |
| choose a random 48-bit number with its eighth bit set to 1 as recommended |
| in RFC 4122. |
| """ |
| |
| global _node |
| if _node is not None: |
| return _node |
| |
| import sys |
| if sys.platform == 'win32': |
| getters = [_windll_getnode, _netbios_getnode, _ipconfig_getnode] |
| else: |
| getters = [_unixdll_getnode, _ifconfig_getnode] |
| |
| for getter in getters + [_random_getnode]: |
| try: |
| _node = getter() |
| except: |
| continue |
| if _node is not None: |
| return _node |
| |
| _last_timestamp = None |
| |
| def uuid1(node=None, clock_seq=None): |
| """Generate a UUID from a host ID, sequence number, and the current time. |
| If 'node' is not given, getnode() is used to obtain the hardware |
| address. If 'clock_seq' is given, it is used as the sequence number; |
| otherwise a random 14-bit sequence number is chosen.""" |
| |
| # When the system provides a version-1 UUID generator, use it (but don't |
| # use UuidCreate here because its UUIDs don't conform to RFC 4122). |
| if _uuid_generate_time and node is clock_seq is None: |
| _buffer = ctypes.create_string_buffer(16) |
| _uuid_generate_time(_buffer) |
| return UUID(bytes=bytes_(_buffer.raw)) |
| |
| global _last_timestamp |
| import time |
| nanoseconds = int(time.time() * 1e9) |
| # 0x01b21dd213814000 is the number of 100-ns intervals between the |
| # UUID epoch 1582-10-15 00:00:00 and the Unix epoch 1970-01-01 00:00:00. |
| timestamp = int(nanoseconds/100) + 0x01b21dd213814000 |
| if _last_timestamp is not None and timestamp <= _last_timestamp: |
| timestamp = _last_timestamp + 1 |
| _last_timestamp = timestamp |
| if clock_seq is None: |
| import random |
| clock_seq = random.randrange(1<<14) # instead of stable storage |
| time_low = timestamp & 0xffffffff |
| time_mid = (timestamp >> 32) & 0xffff |
| time_hi_version = (timestamp >> 48) & 0x0fff |
| clock_seq_low = clock_seq & 0xff |
| clock_seq_hi_variant = (clock_seq >> 8) & 0x3f |
| if node is None: |
| node = getnode() |
| return UUID(fields=(time_low, time_mid, time_hi_version, |
| clock_seq_hi_variant, clock_seq_low, node), version=1) |
| |
| def uuid3(namespace, name): |
| """Generate a UUID from the MD5 hash of a namespace UUID and a name.""" |
| from hashlib import md5 |
| hash = md5(namespace.bytes + bytes(name, "utf-8")).digest() |
| return UUID(bytes=hash[:16], version=3) |
| |
| def uuid4(): |
| """Generate a random UUID.""" |
| |
| # When the system provides a version-4 UUID generator, use it. |
| if _uuid_generate_random: |
| _buffer = ctypes.create_string_buffer(16) |
| _uuid_generate_random(_buffer) |
| return UUID(bytes=bytes_(_buffer.raw)) |
| |
| # Otherwise, get randomness from urandom or the 'random' module. |
| try: |
| import os |
| return UUID(bytes=os.urandom(16), version=4) |
| except: |
| import random |
| bytes = bytes_(random.randrange(256) for i in range(16)) |
| return UUID(bytes=bytes, version=4) |
| |
| def uuid5(namespace, name): |
| """Generate a UUID from the SHA-1 hash of a namespace UUID and a name.""" |
| from hashlib import sha1 |
| hash = sha1(namespace.bytes + bytes(name, "utf-8")).digest() |
| return UUID(bytes=hash[:16], version=5) |
| |
| # The following standard UUIDs are for use with uuid3() or uuid5(). |
| |
| NAMESPACE_DNS = UUID('6ba7b810-9dad-11d1-80b4-00c04fd430c8') |
| NAMESPACE_URL = UUID('6ba7b811-9dad-11d1-80b4-00c04fd430c8') |
| NAMESPACE_OID = UUID('6ba7b812-9dad-11d1-80b4-00c04fd430c8') |
| NAMESPACE_X500 = UUID('6ba7b814-9dad-11d1-80b4-00c04fd430c8') |