73 lines
1.9 KiB
Python
73 lines
1.9 KiB
Python
"""Utility functions and classes for the stix2 library."""
|
|
|
|
import json
|
|
import datetime as dt
|
|
from dateutil import parser
|
|
import pytz
|
|
|
|
# Sentinel value for fields that should be set to the current time.
|
|
# We can't use the standard 'default' approach, since if there are multiple
|
|
# timestamps in a single object, the timestamps will vary by a few microseconds.
|
|
NOW = object()
|
|
|
|
|
|
def get_timestamp():
|
|
return dt.datetime.now(tz=pytz.UTC)
|
|
|
|
|
|
def format_datetime(dttm):
|
|
# 1. Convert to timezone-aware
|
|
# 2. Convert to UTC
|
|
# 3. Format in ISO format
|
|
# 4. Add subsecond value if non-zero
|
|
# 5. Add "Z"
|
|
|
|
try:
|
|
zoned = dttm.astimezone(pytz.utc)
|
|
except ValueError:
|
|
# dttm is timezone-naive; assume UTC
|
|
pytz.utc.localize(dttm)
|
|
ts = zoned.strftime("%Y-%m-%dT%H:%M:%S")
|
|
if zoned.microsecond > 0:
|
|
ms = zoned.strftime("%f")
|
|
ts = ts + '.' + ms.rstrip("0")
|
|
return ts + "Z"
|
|
|
|
|
|
def parse_into_datetime(value):
|
|
if isinstance(value, dt.date):
|
|
if hasattr(value, 'hour'):
|
|
return value
|
|
else:
|
|
# Add a time component
|
|
return dt.datetime.combine(value, dt.time(), tzinfo=pytz.utc)
|
|
|
|
# value isn't a date or datetime object so assume it's a string
|
|
try:
|
|
parsed = parser.parse(value)
|
|
except TypeError:
|
|
# Unknown format
|
|
raise ValueError("must be a datetime object, date object, or "
|
|
"timestamp string in a recognizable format.")
|
|
if parsed.tzinfo:
|
|
return parsed.astimezone(pytz.utc)
|
|
else:
|
|
# Doesn't have timezone info in the string; assume UTC
|
|
return pytz.utc.localize(parsed)
|
|
|
|
|
|
def get_dict(data):
|
|
"""Return data as a dictionary.
|
|
Input can be a dictionary, string, or file-like object.
|
|
"""
|
|
|
|
if type(data) is dict:
|
|
obj = data
|
|
else:
|
|
try:
|
|
obj = json.loads(data)
|
|
except TypeError:
|
|
obj = json.load(data)
|
|
|
|
return obj
|