openc2lib.types.data.datetime

 1import datetime 
 2
 3class DateTime:
 4	""" OpenC2 Date-Time
 5
 6		This is used to represents dates and times according to Sec. 3.4.2.2.
 7		 According to OpenC2 specification, this is the time in milliseconds from the epoch.
 8		Be careful that the `timedate` functions work with float timestamps expressed 
 9		in seconds from the epoch, hence conversion is needed.
10	"""
11	def __init__(self, timestamp=None):
12		""" Initialize Date-Time
13			
14			The instance is initialized with the provided timestamp, or to the current time if no 
15			argument is given. The timestamp is expressed in milliseconds
16				from the epoch, according to the Language Specification.
17			:param timestamp: The timestamp to initialize the instance.
18		"""
19		self.update(timestamp)
20
21	def __str__(self):
22		return str(self.time)
23
24	def __int__(self):
25		return self.time
26
27	def update(self, timestamp=None):
28		""" Change Date-Time
29
30			Change the timestamp beard by the instance. The timestamp is expressed in milliseconds
31			from the epoch. If no `timestamp` is given, sets to the current time.
32			:param timestamp: The timestamp to initialize the instance.
33		"""
34		if timestamp == None:
35			# datetime.timestamp() returns a float in seconds
36			self.time = int(datetime.datetime.now(datetime.timezone.utc).timestamp()*1000)
37		else:
38			self.time = timestamp
39
40	# RFC 7231       
41	def httpdate(self, timestamp=None):
42		""" Format  to HTTP headers
43
44			Formats the timestamp according to the requirements of HTTP headers (RFC 7231).
45			Use either the `timestamp`, if provided,  or the current time.
46			:param timestamp: The timestamp to format, expressed in milliseconds from the epoch.
47			:return RFC 7231 representation of the `timestamp`.
48		"""
49			
50		if timestamp is None:
51			timestamp = self.time
52
53		return datetime.datetime.fromtimestamp(timestamp/1000).strftime('%a, %d %b %Y %H:%M:%S %Z')