Convert string to datetime, add one hour, and then convert it back to string-CodePudding

I have a specific string time format (I think it's ISO) that need to be added 1 hour to. So, I need to convert it to datetime first, then add 1 hour to it, and then finally convert it back to string. I'm having trouble creating the right format pattern for it. Any help is appreciated.

from datetime import datetime,timedelta

# Convert string to datetime
timestamp = '2022-12-23T16:21:14.529Z' #timestamp string
format = ('%Y-%m-%dT%H:%M:%S.%f')[:-3] 'Z' #format pattern

to_datetime = datetime.strptime(timestamp,format) #convert to datetime
add1_hour = (to_datetime   timedelta(hours=1)) #add one hour
print(type(add1_hour),add1_hour)


#Convert datetime to string
to_string = str(add1_hour)
print(type(to_string),to_string)

Output:

Traceback (most recent call last):
  File "c:\Users\user\Desktop\PYTHON_PROJECTS\tiny3.py", line 259, in <module>
    to_datetime = datetime.strptime(timestamp,format) #convert to datetime
  File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.10_3.10.2544.0_x64__qbz5n2kfra8p0\lib\_strptime.py", line 568, in _strptime_datetime
    tt, fraction, gmtoff_fraction = _strptime(data_string, format)
  File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.10_3.10.2544.0_x64__qbz5n2kfra8p0\lib\_strptime.py", line 349, in _strptime
    raise ValueError("time data %r does not match format %r" %
ValueError: time data '2022-12-23T16:21:14.529Z' does not match format '%Y-%m-%dT%H:%M:%SZ'

CodePudding user response：

You can just use the built in methods for parsing and writing ISO formatted timestamps. You'll have to remove and reattach the 'Z' manually since it's not supported:

from datetime import datetime, timedelta

def alter_timestamp(timestamp, delta):
    dt = datetime.fromisoformat(timestamp[:-1])
    return (dt   delta).isoformat(timespec='milliseconds')   'Z'

timestamp = '2022-12-23T16:21:14.529Z'
hour_added = alter_timestamp(timestamp, timedelta(hours=1))
print(hour_added)
# '2022-12-23T17:21:14.529Z'

CodePudding user response：

If all your timestamps are UTC, I think you can include Z in the format string and it will parse correctly?

from datetime import datetime, timedelta

# Convert string to datetime
timestamp = '2022-12-23T16:21:14.529Z'  # timestamp string
to_datetime = datetime.strptime(timestamp, '%Y-%m-%dT%H:%M:%S.%fZ')  # convert to datetime

add1_hour = (to_datetime   timedelta(hours=1))  # add one hour
print(type(add1_hour), add1_hour)

# Convert datetime to string
to_string = str(add1_hour)
print(type(to_string), to_string)

Output:

<class 'datetime.datetime'> 2022-12-23 17:21:14.529000
<class 'str'> 2022-12-23 17:21:14.529000

CodePudding user response：

The arrow module will make this much easier:

import arrow

timestamp = '2022-12-23T16:21:14.529Z'
print(arrow.get(timestamp), arrow.get(timestamp).shift(hours=1))

Output:

2022-12-23T16:21:14.529000 00:00 2022-12-23T17:21:14.529000 00:00