python: which file is newer & by how much time - python

I am trying to create a filedate comparison routine. I suspect that the following is a rather clunky approach.
I had some difficulty finding info about timedelta's attributes or methods, or whatever they are called; hence, I measured the datetime difference below only in terms of days, minutes and seconds, and there is no list item representing years.
Any suggestions for an alternative, would be much appreciated.
import os
import datetime
from datetime import datetime
import sys
def datetime_filedif(filepath1e, filepath2e):
filelpath1 = str(filepath1e)
filepath1 = str(filepath1e)
filepath2 = str(filepath2e)
filepath1_lmdate = datetime.fromtimestamp(os.path.getmtime(filepath1))
filepath2_lmdate = datetime.fromtimestamp(os.path.getmtime(filepath2))
td_files = filepath2_lmdate - filepath1_lmdate #Time delta of the 2 filedates
td_list = [('td_files.days', td_files.days), ('td_hrs', int(str(td_files.seconds))/3600), ('td_minutes', (int(str(td_files.seconds))%3600)/60), ('td_seconds', (int(str(td_files.seconds))%3600)%60)]
print "Line 25: ", str(td_list)
return td_list

There is a solution for that already:
import os
modified_time = os.stat(path).st_mtime # time of most recent content modification
diff_time = os.stat(path_1).st_mtime - os.stat(path_2).st_mtime
Now you have the time in seconds since Epoch. why are you creating a new representation, you can create a deltatime or whatever from this, why invent a new format?

Related

How to get ceiling of seconds in a timedelta object [duplicate]

Currently I am logging stuff and I am using my own formatter with a custom formatTime():
def formatTime(self, _record, _datefmt):
t = datetime.datetime.now()
return t.strftime('%Y-%m-%d %H:%M:%S.%f')
My issue is that the microseconds, %f, are six digits. Is there anyway to spit out less digits, like the first three digits of the microseconds?
The simplest way would be to use slicing to just chop off the last three digits of the microseconds:
def format_time():
t = datetime.datetime.now()
s = t.strftime('%Y-%m-%d %H:%M:%S.%f')
return s[:-3]
I strongly recommend just chopping. I once wrote some logging code that rounded the timestamps rather than chopping, and I found it actually kind of confusing when the rounding changed the last digit. There was timed code that stopped running at a certain timestamp yet there were log events with that timestamp due to the rounding. Simpler and more predictable to just chop.
If you want to actually round the number rather than just chopping, it's a little more work but not horrible:
def format_time():
t = datetime.datetime.now()
s = t.strftime('%Y-%m-%d %H:%M:%S.%f')
head = s[:-7] # everything up to the '.'
tail = s[-7:] # the '.' and the 6 digits after it
f = float(tail)
temp = "{:.03f}".format(f) # for Python 2.x: temp = "%.3f" % f
new_tail = temp[1:] # temp[0] is always '0'; get rid of it
return head + new_tail
Obviously you can simplify the above with fewer variables; I just wanted it to be very easy to follow.
As of Python 3.6 the language has this feature built in:
def format_time():
t = datetime.datetime.now()
s = t.isoformat(timespec='milliseconds')
return s
This method should always return a timestamp that looks exactly like this (with or without the timezone depending on whether the input dt object contains one):
2016-08-05T18:18:54.776+0000
It takes a datetime object as input (which you can produce with datetime.datetime.now()). To get the time zone like in my example output you'll need to import pytz and pass datetime.datetime.now(pytz.utc).
import pytz, datetime
time_format(datetime.datetime.now(pytz.utc))
def time_format(dt):
return "%s:%.3f%s" % (
dt.strftime('%Y-%m-%dT%H:%M'),
float("%.3f" % (dt.second + dt.microsecond / 1e6)),
dt.strftime('%z')
)
I noticed that some of the other methods above would omit the trailing zero if there was one (e.g. 0.870 became 0.87) and this was causing problems for the parser I was feeding these timestamps into. This method does not have that problem.
An easy solution that should work in all cases:
def format_time():
t = datetime.datetime.now()
if t.microsecond % 1000 >= 500: # check if there will be rounding up
t = t + datetime.timedelta(milliseconds=1) # manually round up
return t.strftime('%Y-%m-%d %H:%M:%S.%f')[:-3]
Basically you do manual rounding on the date object itself first, then you can safely trim the microseconds.
Edit: As some pointed out in the comments below, the rounding of this solution (and the one above) introduces problems when the microsecond value reaches 999500, as 999.5 is rounded to 1000 (overflow).
Short of reimplementing strftime to support the format we want (the potential overflow caused by the rounding would need to be propagated up to seconds, then minutes, etc.), it is much simpler to just truncate to the first 3 digits as outlined in the accepted answer, or using something like:
'{:03}'.format(int(999999/1000))
-- Original answer preserved below --
In my case, I was trying to format a datestamp with milliseconds formatted as 'ddd'. The solution I ended up using to get milliseconds was to use the microsecond attribute of the datetime object, divide it by 1000.0, pad it with zeros if necessary, and round it with format. It looks like this:
'{:03.0f}'.format(datetime.now().microsecond / 1000.0)
# Produces: '033', '499', etc.
You can subtract the current datetime from the microseconds.
d = datetime.datetime.now()
current_time = d - datetime.timedelta(microseconds=d.microsecond)
This will turn 2021-05-14 16:11:21.916229 into 2021-05-14 16:11:21
This method allows flexible precision and will consume the entire microsecond value if you specify too great a precision.
def formatTime(self, _record, _datefmt, precision=3):
dt = datetime.datetime.now()
us = str(dt.microsecond)
f = us[:precision] if len(us) > precision else us
return "%d-%d-%d %d:%d:%d.%d" % (dt.year, dt.month, dt.day, dt.hour, dt.minute, dt.second, int(f))
This method implements rounding to 3 decimal places:
import datetime
from decimal import *
def formatTime(self, _record, _datefmt, precision='0.001'):
dt = datetime.datetime.now()
seconds = float("%d.%d" % (dt.second, dt.microsecond))
return "%d-%d-%d %d:%d:%s" % (dt.year, dt.month, dt.day, dt.hour, dt.minute,
float(Decimal(seconds).quantize(Decimal(precision), rounding=ROUND_HALF_UP)))
I avoided using the strftime method purposely because I would prefer not to modify a fully serialized datetime object without revalidating it. This way also shows the date internals in case you want to modify it further.
In the rounding example, note that the precision is string-based for the Decimal module.
Here is my solution using regexp:
import re
# Capture 6 digits after dot in a group.
regexp = re.compile(r'\.(\d{6})')
def to_splunk_iso(dt):
"""Converts the datetime object to Splunk isoformat string."""
# 6-digits string.
microseconds = regexp.search(dt.isoformat()).group(1)
return regexp.sub('.%d' % round(float(microseconds) / 1000), dt.isoformat())
Fixing the proposed solution based on Pablojim Comments:
from datetime import datetime
dt = datetime.now()
dt_round_microsec = round(dt.microsecond/1000) #number of zeroes to round
dt = dt.replace(microsecond=dt_round_microsec)
If once want to get the day of the week (i.e, 'Sunday)' along with the result, then by slicing '[:-3]' will not work. At that time you may go with,
dt = datetime.datetime.now()
print("{}.{:03d} {}".format(dt.strftime('%Y-%m-%d %I:%M:%S'), dt.microsecond//1000, dt.strftime("%A")))
#Output: '2019-05-05 03:11:22.211 Sunday'
%H - for 24 Hour format
%I - for 12 Hour format
Thanks,
Adding my two cents here as this method will allow you to write your microsecond format as you would a float in c-style. It takes advantage that they both use %f.
import datetime
import re
def format_datetime(date, format):
"""Format a ``datetime`` object with microsecond precision.
Pass your microsecond as you would format a c-string float.
e.g "%.3f"
Args:
date (datetime.datetime): You input ``datetime`` obj.
format (str): Your strftime format string.
Returns:
str: Your formatted datetime string.
"""
# We need to check if formatted_str contains "%.xf" (x = a number)
float_format = r"(%\.\d+f)"
has_float_format = re.search(float_format, format)
if has_float_format:
# make microseconds be decimal place. Might be a better way to do this
microseconds = date.microsecond
while int(microseconds): # quit once it's 0
microseconds /= 10
ms_str = has_float_format.group(1) % microseconds
format = re.sub(float_format, ms_str[2:], format)
return date.strftime(format)
print(datetime.datetime.now(), "%H:%M:%S.%.3f")
# '17:58:54.424'

ValueError: time data '2021-04-06T23:51:50.514Z' does not match format '%Y-%m-%dT%H:%M:%SZ' when converting ISO 8601 [duplicate]

This question already has answers here:
How do I parse an ISO 8601-formatted date?
(29 answers)
Closed 8 years ago.
The community reviewed whether to reopen this question last month and left it closed:
Original close reason(s) were not resolved
I'm getting a datetime string in a format like "2009-05-28T16:15:00" (this is ISO 8601, I believe). One hackish option seems to be to parse the string using time.strptime and passing the first six elements of the tuple into the datetime constructor, like:
datetime.datetime(*time.strptime("2007-03-04T21:08:12", "%Y-%m-%dT%H:%M:%S")[:6])
I haven't been able to find a "cleaner" way of doing this. Is there one?
I prefer using the dateutil library for timezone handling and generally solid date parsing. If you were to get an ISO 8601 string like: 2010-05-08T23:41:54.000Z you'd have a fun time parsing that with strptime, especially if you didn't know up front whether or not the timezone was included. pyiso8601 has a couple of issues (check their tracker) that I ran into during my usage and it hasn't been updated in a few years. dateutil, by contrast, has been active and worked for me:
from dateutil import parser
yourdate = parser.parse(datestring)
Since Python 3.7 and no external libraries, you can use the fromisoformat function from the datetime module:
datetime.datetime.fromisoformat('2019-01-04T16:41:24+02:00')
Python 2 doesn't support the %z format specifier, so it's best to explicitly use Zulu time everywhere if possible:
datetime.datetime.strptime("2007-03-04T21:08:12Z", "%Y-%m-%dT%H:%M:%SZ")
Because ISO 8601 allows many variations of optional colons and dashes being present, basically CCYY-MM-DDThh:mm:ss[Z|(+|-)hh:mm]. If you want to use strptime, you need to strip out those variations first.
The goal is to generate a UTC datetime object.
If you just want a basic case that work for UTC with the Z suffix like 2016-06-29T19:36:29.3453Z:
datetime.datetime.strptime(timestamp.translate(None, ':-'), "%Y%m%dT%H%M%S.%fZ")
If you want to handle timezone offsets like 2016-06-29T19:36:29.3453-0400 or 2008-09-03T20:56:35.450686+05:00 use the following. These will convert all variations into something without variable delimiters like 20080903T205635.450686+0500 making it more consistent/easier to parse.
import re
# This regex removes all colons and all
# dashes EXCEPT for the dash indicating + or - utc offset for the timezone
conformed_timestamp = re.sub(r"[:]|([-](?!((\d{2}[:]\d{2})|(\d{4}))$))", '', timestamp)
datetime.datetime.strptime(conformed_timestamp, "%Y%m%dT%H%M%S.%f%z" )
If your system does not support the %z strptime directive (you see something like ValueError: 'z' is a bad directive in format '%Y%m%dT%H%M%S.%f%z') then you need to manually offset the time from Z (UTC). Note %z may not work on your system in Python versions < 3 as it depended on the C library support which varies across system/Python build type (i.e., Jython, Cython, etc.).
import re
import datetime
# This regex removes all colons and all
# dashes EXCEPT for the dash indicating + or - utc offset for the timezone
conformed_timestamp = re.sub(r"[:]|([-](?!((\d{2}[:]\d{2})|(\d{4}))$))", '', timestamp)
# Split on the offset to remove it. Use a capture group to keep the delimiter
split_timestamp = re.split(r"([+|-])",conformed_timestamp)
main_timestamp = split_timestamp[0]
if len(split_timestamp) == 3:
sign = split_timestamp[1]
offset = split_timestamp[2]
else:
sign = None
offset = None
# Generate the datetime object without the offset at UTC time
output_datetime = datetime.datetime.strptime(main_timestamp +"Z", "%Y%m%dT%H%M%S.%fZ" )
if offset:
# Create timedelta based on offset
offset_delta = datetime.timedelta(hours=int(sign+offset[:-2]), minutes=int(sign+offset[-2:]))
# Offset datetime with timedelta
output_datetime = output_datetime + offset_delta
Arrow looks promising for this:
>>> import arrow
>>> arrow.get('2014-11-13T14:53:18.694072+00:00').datetime
datetime.datetime(2014, 11, 13, 14, 53, 18, 694072, tzinfo=tzoffset(None, 0))
Arrow is a Python library that provides a sensible, intelligent way of creating, manipulating, formatting and converting dates and times. Arrow is simple, lightweight and heavily inspired by moment.js and requests.
You should keep an eye on the timezone information, as you might get into trouble when comparing non-tz-aware datetimes with tz-aware ones.
It's probably the best to always make them tz-aware (even if only as UTC), unless you really know why it wouldn't be of any use to do so.
#-----------------------------------------------
import datetime
import pytz
import dateutil.parser
#-----------------------------------------------
utc = pytz.utc
BERLIN = pytz.timezone('Europe/Berlin')
#-----------------------------------------------
def to_iso8601(when=None, tz=BERLIN):
if not when:
when = datetime.datetime.now(tz)
if not when.tzinfo:
when = tz.localize(when)
_when = when.strftime("%Y-%m-%dT%H:%M:%S.%f%z")
return _when[:-8] + _when[-5:] # Remove microseconds
#-----------------------------------------------
def from_iso8601(when=None, tz=BERLIN):
_when = dateutil.parser.parse(when)
if not _when.tzinfo:
_when = tz.localize(_when)
return _when
#-----------------------------------------------
I haven't tried it yet, but pyiso8601 promises to support this.
import datetime, time
def convert_enddate_to_seconds(self, ts):
"""Takes ISO 8601 format(string) and converts into epoch time."""
dt = datetime.datetime.strptime(ts[:-7],'%Y-%m-%dT%H:%M:%S.%f')+\
datetime.timedelta(hours=int(ts[-5:-3]),
minutes=int(ts[-2:]))*int(ts[-6:-5]+'1')
seconds = time.mktime(dt.timetuple()) + dt.microsecond/1000000.0
return seconds
This also includes the milliseconds and time zone.
If the time is '2012-09-30T15:31:50.262-08:00', this will convert into epoch time.
>>> import datetime, time
>>> ts = '2012-09-30T15:31:50.262-08:00'
>>> dt = datetime.datetime.strptime(ts[:-7],'%Y-%m-%dT%H:%M:%S.%f')+ datetime.timedelta(hours=int(ts[-5:-3]), minutes=int(ts[-2:]))*int(ts[-6:-5]+'1')
>>> seconds = time.mktime(dt.timetuple()) + dt.microsecond/1000000.0
>>> seconds
1348990310.26
Both ways:
Epoch to ISO time:
isoTime = time.strftime('%Y-%m-%dT%H:%M:%SZ', time.gmtime(epochTime))
ISO time to Epoch:
epochTime = time.mktime(time.strptime(isoTime, '%Y-%m-%dT%H:%M:%SZ'))
Isodate seems to have the most complete support.
aniso8601 should handle this. It also understands timezones, Python 2 and Python 3, and it has a reasonable coverage of the rest of ISO 8601, should you ever need it.
import aniso8601
aniso8601.parse_datetime('2007-03-04T21:08:12')
Here is a super simple way to do these kind of conversions.
No parsing, or extra libraries required.
It is clean, simple, and fast.
import datetime
import time
################################################
#
# Takes the time (in seconds),
# and returns a string of the time in ISO8601 format.
# Note: Timezone is UTC
#
################################################
def TimeToISO8601(seconds):
strKv = datetime.datetime.fromtimestamp(seconds).strftime('%Y-%m-%d')
strKv = strKv + "T"
strKv = strKv + datetime.datetime.fromtimestamp(seconds).strftime('%H:%M:%S')
strKv = strKv +"Z"
return strKv
################################################
#
# Takes a string of the time in ISO8601 format,
# and returns the time (in seconds).
# Note: Timezone is UTC
#
################################################
def ISO8601ToTime(strISOTime):
K1 = 0
K2 = 9999999999
K3 = 0
counter = 0
while counter < 95:
K3 = (K1 + K2) / 2
strK4 = TimeToISO8601(K3)
if strK4 < strISOTime:
K1 = K3
if strK4 > strISOTime:
K2 = K3
counter = counter + 1
return K3
################################################
#
# Takes a string of the time in ISO8601 (UTC) format,
# and returns a python DateTime object.
# Note: returned value is your local time zone.
#
################################################
def ISO8601ToDateTime(strISOTime):
return time.gmtime(ISO8601ToTime(strISOTime))
#To test:
Test = "2014-09-27T12:05:06.9876"
print ("The test value is: " + Test)
Ans = ISO8601ToTime(Test)
print ("The answer in seconds is: " + str(Ans))
print ("And a Python datetime object is: " + str(ISO8601ToDateTime(Test)))

How to mock datetime in just one file?

I have two files in which I use datetime. Is there a way to mock it in just one file and not the other? Following is an example of where I'm seeing a weird behavior.
File: test_file_one.py
import datetime as dt
def print_datetime():
print 'First: {}'.format(dt.datetime.utcnow())
File: test_file_two.py
import datetime as dt
def print_datetime():
print 'Second: {}'.format(dt.datetime.utcnow())
File: main.py
import test_file_one as first
import test_file_two as second
import mock
from datetime import datetime, timedelta
#mock.patch('test_file_one.dt.datetime')
def main(mock_datetime):
mock_datetime.utcnow.return_value = datetime.utcnow() + timedelta(days=1)
first.print_datetime()
second.print_datetime()
if __name__ == '__main__':
main()
Output
First: 2018-06-12 08:12:43.838243
Second: 2018-06-12 08:12:43.838243
As you see, both return the same datetime which was mocked.
Why are both mocked?
How to limit the mock to just one file?
You can just add as many results you calls you want to do to side_effect
mock_datetime.utcnow.side_effect = [datetime.utcnow() + timedelta(days=1), datetime.utcnow() + timedelta(days=2)]
I'd suggest you to reduce the scope of your mocking.
Now you are applying your mock to the whole method by using the decorator #mock.patch('test_file_one.dt.datetime')
Instead you could try something like:
def main(mock_datetime):
with mock.patch('test_file_one.dt.datetime') as mock_datetime:
mock_datetime.utcnow.return_value = datetime.utcnow() + timedelta(days=1)
first.print_datetime()
second.print_datetime()
As an alternative, you could use fake_time method from libfaketime-tz-wrapper library.
Then your approach would be something like:
from libfaketime_tz_wrapper import fake_time
def main(mock_datetime):
with fake_time(datetime.utcnow() + timedelta(days=1)):
first.print_datetime()
second.print_datetime()
I didn't test if my suggestions work, but I've been using fake_time a lot in the last 1,5 year and seems to be very handful on issues like this.

How to get real three digits of microseconds in Python?

I'm trying to increase the time.
I want to get an hour format like this: 13:30:45,123 (in Java: "HH:mm:ss,SSS"), but Python displays 13:30:45,123456 ("%H:%M:%S,%f")(microseconds of 6 digits).
I read on the web and found possible solutions like:
from datetime import datetime
hour = datetime.utcnow().strftime('%H:%M:%S,%f')[:-3]
print(hour)
The output is: 04:33:16,123
But it's a bad solution, because if the hour is for example: 01:49:56,020706, the output is: 01:49:56,020, that the right should be: 01:49:56,021 (rounded).
The real purpose is that if I increase the milliseconds, even reaching rounds the seconds.
Example: (I want to increase 500 microseconds)
If the Input: 00:01:48,557, the Output should be: 00:01:49,057
The code of the program in Java (working good) is:
SimpleDateFormat df = new SimpleDateFormat("HH:mm:ss,SSS");
System.out.print("Input the time: ");
t1 = in.next();
Date d = df.parse(t1);
Calendar cal = Calendar.getInstance();
cal.setTime(d);
cal.add(Calendar.MILLISECOND, 500);//here increase the milliseconds (microseconds)
t2 = df.format(cal.getTime());
System.out.print("The Output (+500): "+t2);
I don't know if exists in Python something like SimpleDateFormat (in Java).
As to addition, you can add 500ms to your datetime object, using a timedelta object:
from datetime import datetime, timedelta
t1 = datetime.utcnow()
t2 = t1 + timedelta(milliseconds=500)
So as long as you're working with datetime objects instead of strings, you can easily do all the time-operations you'd like.
So we're left with the question of how to format the time when you want to display it.
As you pointed out, the [:-3]-trick seems to be the common solution, and seems to me it should work fine. If you really care about rounding correctly to the closest round millisecond, you can use the following "rounding trick":
You must have seen this trick in the past, for floats:
def round(x):
return int(x + 0.5)
The same idea (i.e. adding 0.5) can also be applied to datetimes:
def format_dt(t):
tr = t + timedelta(milliseconds=0.5)
return tr.strftime('%H:%M:%S,%f')[:-3]
You can round of digits using decimal
from decimal import Decimal
ts = datetime.utcnow()
sec = Decimal(ts.strftime('%S.%f'))
print ts.strftime('%H:%M:')+str(round(sec, 3))

How do I translate an ISO 8601 datetime string into a Python datetime object? [duplicate]

This question already has answers here:
How do I parse an ISO 8601-formatted date?
(29 answers)
Closed 8 years ago.
The community reviewed whether to reopen this question last month and left it closed:
Original close reason(s) were not resolved
I'm getting a datetime string in a format like "2009-05-28T16:15:00" (this is ISO 8601, I believe). One hackish option seems to be to parse the string using time.strptime and passing the first six elements of the tuple into the datetime constructor, like:
datetime.datetime(*time.strptime("2007-03-04T21:08:12", "%Y-%m-%dT%H:%M:%S")[:6])
I haven't been able to find a "cleaner" way of doing this. Is there one?
I prefer using the dateutil library for timezone handling and generally solid date parsing. If you were to get an ISO 8601 string like: 2010-05-08T23:41:54.000Z you'd have a fun time parsing that with strptime, especially if you didn't know up front whether or not the timezone was included. pyiso8601 has a couple of issues (check their tracker) that I ran into during my usage and it hasn't been updated in a few years. dateutil, by contrast, has been active and worked for me:
from dateutil import parser
yourdate = parser.parse(datestring)
Since Python 3.7 and no external libraries, you can use the fromisoformat function from the datetime module:
datetime.datetime.fromisoformat('2019-01-04T16:41:24+02:00')
Python 2 doesn't support the %z format specifier, so it's best to explicitly use Zulu time everywhere if possible:
datetime.datetime.strptime("2007-03-04T21:08:12Z", "%Y-%m-%dT%H:%M:%SZ")
Because ISO 8601 allows many variations of optional colons and dashes being present, basically CCYY-MM-DDThh:mm:ss[Z|(+|-)hh:mm]. If you want to use strptime, you need to strip out those variations first.
The goal is to generate a UTC datetime object.
If you just want a basic case that work for UTC with the Z suffix like 2016-06-29T19:36:29.3453Z:
datetime.datetime.strptime(timestamp.translate(None, ':-'), "%Y%m%dT%H%M%S.%fZ")
If you want to handle timezone offsets like 2016-06-29T19:36:29.3453-0400 or 2008-09-03T20:56:35.450686+05:00 use the following. These will convert all variations into something without variable delimiters like 20080903T205635.450686+0500 making it more consistent/easier to parse.
import re
# This regex removes all colons and all
# dashes EXCEPT for the dash indicating + or - utc offset for the timezone
conformed_timestamp = re.sub(r"[:]|([-](?!((\d{2}[:]\d{2})|(\d{4}))$))", '', timestamp)
datetime.datetime.strptime(conformed_timestamp, "%Y%m%dT%H%M%S.%f%z" )
If your system does not support the %z strptime directive (you see something like ValueError: 'z' is a bad directive in format '%Y%m%dT%H%M%S.%f%z') then you need to manually offset the time from Z (UTC). Note %z may not work on your system in Python versions < 3 as it depended on the C library support which varies across system/Python build type (i.e., Jython, Cython, etc.).
import re
import datetime
# This regex removes all colons and all
# dashes EXCEPT for the dash indicating + or - utc offset for the timezone
conformed_timestamp = re.sub(r"[:]|([-](?!((\d{2}[:]\d{2})|(\d{4}))$))", '', timestamp)
# Split on the offset to remove it. Use a capture group to keep the delimiter
split_timestamp = re.split(r"([+|-])",conformed_timestamp)
main_timestamp = split_timestamp[0]
if len(split_timestamp) == 3:
sign = split_timestamp[1]
offset = split_timestamp[2]
else:
sign = None
offset = None
# Generate the datetime object without the offset at UTC time
output_datetime = datetime.datetime.strptime(main_timestamp +"Z", "%Y%m%dT%H%M%S.%fZ" )
if offset:
# Create timedelta based on offset
offset_delta = datetime.timedelta(hours=int(sign+offset[:-2]), minutes=int(sign+offset[-2:]))
# Offset datetime with timedelta
output_datetime = output_datetime + offset_delta
Arrow looks promising for this:
>>> import arrow
>>> arrow.get('2014-11-13T14:53:18.694072+00:00').datetime
datetime.datetime(2014, 11, 13, 14, 53, 18, 694072, tzinfo=tzoffset(None, 0))
Arrow is a Python library that provides a sensible, intelligent way of creating, manipulating, formatting and converting dates and times. Arrow is simple, lightweight and heavily inspired by moment.js and requests.
You should keep an eye on the timezone information, as you might get into trouble when comparing non-tz-aware datetimes with tz-aware ones.
It's probably the best to always make them tz-aware (even if only as UTC), unless you really know why it wouldn't be of any use to do so.
#-----------------------------------------------
import datetime
import pytz
import dateutil.parser
#-----------------------------------------------
utc = pytz.utc
BERLIN = pytz.timezone('Europe/Berlin')
#-----------------------------------------------
def to_iso8601(when=None, tz=BERLIN):
if not when:
when = datetime.datetime.now(tz)
if not when.tzinfo:
when = tz.localize(when)
_when = when.strftime("%Y-%m-%dT%H:%M:%S.%f%z")
return _when[:-8] + _when[-5:] # Remove microseconds
#-----------------------------------------------
def from_iso8601(when=None, tz=BERLIN):
_when = dateutil.parser.parse(when)
if not _when.tzinfo:
_when = tz.localize(_when)
return _when
#-----------------------------------------------
I haven't tried it yet, but pyiso8601 promises to support this.
import datetime, time
def convert_enddate_to_seconds(self, ts):
"""Takes ISO 8601 format(string) and converts into epoch time."""
dt = datetime.datetime.strptime(ts[:-7],'%Y-%m-%dT%H:%M:%S.%f')+\
datetime.timedelta(hours=int(ts[-5:-3]),
minutes=int(ts[-2:]))*int(ts[-6:-5]+'1')
seconds = time.mktime(dt.timetuple()) + dt.microsecond/1000000.0
return seconds
This also includes the milliseconds and time zone.
If the time is '2012-09-30T15:31:50.262-08:00', this will convert into epoch time.
>>> import datetime, time
>>> ts = '2012-09-30T15:31:50.262-08:00'
>>> dt = datetime.datetime.strptime(ts[:-7],'%Y-%m-%dT%H:%M:%S.%f')+ datetime.timedelta(hours=int(ts[-5:-3]), minutes=int(ts[-2:]))*int(ts[-6:-5]+'1')
>>> seconds = time.mktime(dt.timetuple()) + dt.microsecond/1000000.0
>>> seconds
1348990310.26
Both ways:
Epoch to ISO time:
isoTime = time.strftime('%Y-%m-%dT%H:%M:%SZ', time.gmtime(epochTime))
ISO time to Epoch:
epochTime = time.mktime(time.strptime(isoTime, '%Y-%m-%dT%H:%M:%SZ'))
Isodate seems to have the most complete support.
aniso8601 should handle this. It also understands timezones, Python 2 and Python 3, and it has a reasonable coverage of the rest of ISO 8601, should you ever need it.
import aniso8601
aniso8601.parse_datetime('2007-03-04T21:08:12')
Here is a super simple way to do these kind of conversions.
No parsing, or extra libraries required.
It is clean, simple, and fast.
import datetime
import time
################################################
#
# Takes the time (in seconds),
# and returns a string of the time in ISO8601 format.
# Note: Timezone is UTC
#
################################################
def TimeToISO8601(seconds):
strKv = datetime.datetime.fromtimestamp(seconds).strftime('%Y-%m-%d')
strKv = strKv + "T"
strKv = strKv + datetime.datetime.fromtimestamp(seconds).strftime('%H:%M:%S')
strKv = strKv +"Z"
return strKv
################################################
#
# Takes a string of the time in ISO8601 format,
# and returns the time (in seconds).
# Note: Timezone is UTC
#
################################################
def ISO8601ToTime(strISOTime):
K1 = 0
K2 = 9999999999
K3 = 0
counter = 0
while counter < 95:
K3 = (K1 + K2) / 2
strK4 = TimeToISO8601(K3)
if strK4 < strISOTime:
K1 = K3
if strK4 > strISOTime:
K2 = K3
counter = counter + 1
return K3
################################################
#
# Takes a string of the time in ISO8601 (UTC) format,
# and returns a python DateTime object.
# Note: returned value is your local time zone.
#
################################################
def ISO8601ToDateTime(strISOTime):
return time.gmtime(ISO8601ToTime(strISOTime))
#To test:
Test = "2014-09-27T12:05:06.9876"
print ("The test value is: " + Test)
Ans = ISO8601ToTime(Test)
print ("The answer in seconds is: " + str(Ans))
print ("And a Python datetime object is: " + str(ISO8601ToDateTime(Test)))

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