How would I exactly go about offsetting the timestamp returned by datetime.utcnow() by any amount of time such as a day?
For example:
now = datetime.utcnow().isoformat() + 'Z'
I need the above offset by a day. Having a minor issue when my script crosses into the daylight savings time conversion but I dont need to see past it however since it loads today also it dies because the python script errors doing work on the date today now.
To simply add a certain delta time onto UTC add a timedelta:
from datetime import datetime, timedelta
now = (datetime.utcnow() + timedelta(days=3)).isoformat() + 'Z'
print(now)
Output:
2018-11-06T16:55:06.535804Z
More info on python with timezones can be found at Python UTC datetime object's ISO format doesn't include Z (Zulu or Zero offset)
With 3.7 datetime.strptime and datetime.strftime even recognize 01:30 as %z - up to 3.6 the colon would make it crash :)
Related
I'm trying to wrap my head in understanding the implication of using .utcnow vs. .now on Python's DateTime.
Here's the reason for my confusion: I live in France. Right now, we have a +1 hour on the UTC timezone (CET timezone in winter (now) / CEST (+2) timezone in summer).
If I take the following value :
dt = datetime.datetime.utcnow()
dt.strftime('%c') # Thu Dec 9 16:17:38 2021
int(dt.timestamp()) # 1639063064
This is correct as it is, in France right now, 17h17.
So, from my understanding, that timestamp, 1639063064, is the UTC representation of the time since EPOCH.
But if I test this value in the website Epoch Converter, I get
GMT: Thursday 9 December 2021 15:17:44
Your time zone: jeudi 9 décembre 2021 16:17:44 GMT+01:00
It seems that the website ALSO subtracts my timezone to an already "substracted" value, ending in removing twice the timezone and causing an invalid value.
The actual confusion is when I tried to import that UTC timestamp to Luxon on my front app, doing the following doesn't work :
DateTime.fromMillis(parseInt(ts), { zone: 'utc' }).toLocal().setLocale('en')
I'm one hour behind.
How can I "tell" Luxon that the current TS is in the UTC timezone, and calling toLocal will apply the proper user's timezone ?
It seems that the website ALSO substract my timezone t
No, epochconverter.com isn't doing anything. The value 1639063064 really does represent 2021-12-09T15:17:44Z. That's not the value you want.
I'm no Python expert, but I believe the problem is the combination of this utcnow() behavior (emphasis mine):
Return the current UTC date and time, with tzinfo None.
This is like now(), but returns the current UTC date and time, as a naive datetime object.
And this timestamp() behavior:
Naive datetime instances are assumed to represent local time and this method relies on the platform C mktime() function to perform the conversion.
It sounds like you want to follow this advice:
An aware current UTC datetime can be obtained by calling datetime.now(timezone.utc).
So just change your first line to:
dt = datetime.now(timezone.utc)
... and it should be okay.
I am downloading a json file containing timestamp using python . But the timestamp i am getting is below format
`2021-04-01T21:43:52.757Z`
Want to convert into normal timestamp (CST Hrs). I also see that the time is increased by 4 hours when i compare the report manually.
`4/1/2021 5:43:53 PM`
The above hours is 4 hrs less when i compare with json file entry. Please advise me.
You need to use python's datetime module to handle this. The Z in the string actually means time zone 0 or UTC time which is 6 hours ahead of CST not 4:
import datetime
date_object = datetime.datetime.strptime(
"2021-04-01T21:43:52.757Z", "%Y-%m-%dT%H:%M:%S.%fZ"
)
date_object = date_object - datetime.timedelta(hours=6)
print(
f"{date_object.month}/{date_object.day}/{date_object.year} {date_object.strftime('%I:%M:%S %p')}"
)
Which will give this output:
4/1/2021 03:43:52 PM
have to use an f string if you want non zero padded dates because its not available in datetime according to the docs
You can use pytz module to deal with time zones directly and not hardcode them if you want. Or if you are on python 3.9 you can use timezone objects to create timezones yourself
I have the following timestamp 1550588656 which translates to 2019-02-19 15:04:16+00:00 in UTC time convention.
I want to convert it to my country's time convention (UTC or GMT -3 in this time of the year) so it should translate to 2019-02-19 12:04:16+00:00
I have read on other SO questions that first I have to convert the timestamp to an UTC aware Datetime object and then localize it, I'm doing it like this
# string format time
naive_datetime = datetime.fromtimestamp(timestamp).strftime('%Y-%m-%d %H:%M:%S')
# string parse time
naive_datetime = datetime.strptime(naive_datetime, "%Y-%m-%d %H:%M:%S")
# make naive Datetime object UTC aware
utc_datetime = naive_datetime.replace(tzinfo=pytz.UTC)
So now it's not a naive Datetime object, from here I should be able to localize it to my country's timezone. In Python that is pytz.timezone('America/Santiago')
So it should go something like this
cltime = pytz.timezone('America/Santiago')
local_datetime = utc_datetime.astimezone(cltime)
But I'm getting 2019-02-19 09:04:16-03:00 (UTC or GTM -6 ) as a result and I don't know why.
Can someone explain? My intuition tells me it's probably a simple thing I'm not looking at, but I've spent some minutes in it and I haven't been able to tell yet.
If you look at the documentation for fromtimestamp:
Return the local date and time corresponding to the POSIX timestamp
So the problem is that it is already doing a conversion from UTC to the local time, and you're doing it a second time.
First of all you have epoc time (UTC timestamp). You need to convert it into datetime object (native) which is followed by converting native time to aware time and than finally convert it to your local time.
Convert your timestamp to native datetime object
native_datetime = datetime.fromtimestamp(1550588656)
convert native datetime object to aware time (add timezone info, will add timezone info to native timezone UTC for current)
import pytz
utc_time = native_datetime.replace(tzinfo=pytz.timezone("UTC"))
localising aware datetime to your local datetime
local_time = utc_time.astimezone(pytz.timezone("America/Santiago"))
You can replace "America/Santiago" with your local time zone
I think this would help you to solve your problem. Thanks!
I have a wired situation here with returning the time in unix format.
I have this function:
def get_today_date():
nowDate = str(datetime.datetime.utcnow().date())
unix_date = time.mktime(datetime.datetime.strptime(nowDate, "%Y-%m-%d").timetuple())
return (unix_date)
it's straightforward when I print the value of "nowDate" -> it gives me the right value I want (ex: 7/29/2018 00:00:00 UTC) which is correct. But when I change the format from Unix timestamp to date format and get only the date without time, It gives me (7/28/2018).
I've took the value in unix and checked it, it gives me (7/28/2018 21:00:00). Why?
My laptop is in a UTC +3 timezone.
Did something go wrong in the conversion? Or its an internal error in my laptop makes the output wrong?
If you're looking for today's date/time, use datetime.datetime.now(), if you need just the date, use datetime.datetime.today() it's automatically converted into your timezone.
If you play with UTC-based functions, you'll get 3 hours offset for your location, which sometimes might result in time being 21:00 of previous day instead of midnight of the next one -- that's quite reasonable =)
you may use the following approach:
utcnow = datetime.datetime.utcnow()
midnight = time.mktime( datetime.datetime( utcnow.year, utcnow.month, utcnow.day).timetuple() )
I have a database that stores datetime as UTC. I need to look up info from a particular time, but the date and time are given in a local time, let's say 'Europe/Copenhagen'. I'm given these as:
year = 2012; month = 12; day = 2; hour = 13; min = 1;
So, I need to convert these to UTC so I can look them up in the database. I want to do this using pytz. I am looking at localize:
local_tz = timezone('Europe/Copenhagen')
t = local_tz.localize(datetime.datetime(year, month, day, hour, min))
But I'm confused about localize(). Is this assuming that year, etc, are given to me in local time? Or, is it assuming that they they are given in UTC and now it has converted them to local time?
print t gives me:
2012-12-02 13:01:00+01:00
So it seems that it assumed that the original year, etc was in utc; hours is now 13+1 instead of 13. So what should I do instead? I have read the pytz documentation and this does not make it clearer to me. It mentions a lot that things are tricky so I'm not sure whether pytz is actually solving these issues. And, I don't always know if the examples are showing me things that work or things that won't work.
I tried normalize:
print local_tz.normalize(t)
That gives me the same result as print t.
EDIT: With the numbers given above for year etc. it should match up with information in the database for 2012-12-2 12:01. (since Copenhagen is utc+1 on that date)
localize() attaches the timezone to a naive datetime.datetime instance in the local timezone.
If you have datetime values in a local timezone, localize to that timezone, then use .astimezone() to cast the value to UTC:
>>> localdt = local_tz.localize(datetime.datetime(year, month, day, hour, min))
>>> localdt.astimezone(pytz.UTC)
datetime.datetime(2012, 12, 2, 12, 1, tzinfo=<UTC>)
Note that you don't need to do this, datetime objects with a timezone can be compared; they'll both be normalized to UTC for the test:
>>> localdt.astimezone(pytz.UTC) == localdt
True
If you know the incoming time representation is in the Europe/Copenhagen timezone, you can create it as timezone-aware to begin with:
local_tz = timezone('Europe/Copenhagen')
t = local_tz.localize(datetime.datetime(year, month, day, hour, min))
You can then "convert" this to UTC with:
t_utc = t.astimezone(pytz.UTC)
but this might not be necessary, depending on how sane your database drivers are. t and t_utc represent the same point-in-time and well-behaving code should treat them interchangeably. The (year, month, day, hour, minute, second, …) tuple is merely a human-readable representation of this point-in-time in a specific time zone and calendar system.