/bdateutil

Adds business day logic and improved data type flexibility to python-dateutil

Primary LanguagePythonMIT LicenseMIT

bdateutil

Adds business day logic and improved data type flexibility to python-dateutil. 100% backwards compatible with python-dateutil, simply replace dateutil imports with bdateutil.

Example Usage

# Test if a date is a business day
>>> from bdateutil import isbday
>>> isbday(date(2014, 1, 1))
True

# Date parameters are no longer limited to datetime objects
>>> isbday("2014-01-01")
True
>>> isbday("1/1/2014")
True
>>> isbday(1388577600)  # Unix timestamp = Jan 1, 2014
True

# Take into account U.S. statutory holidays
>>> import holidays
>>> isbday("2014-01-01", holidays=holidays.US())
False

# Increment date by two business days
>>> from bdateutil import relativedelta
>>> date(2014, 7, 3) + relativedelta(bdays=+2)
datetime.date(2014, 7, 7)

# Any arguments that take a date/datetime object now accept
# strings/unicode/bytes in any encoding and integer/float timestamps.
# All dateutil functions now also take an optional `holidays` argument
# for helping to work with business days.
>>> "2014-07-03" + relativedelta(bdays=+2, holidays=holidays.US())
datetime.date(2014, 7, 8)

# Determine how many business days between two dates
>>> relativedelta("2014-07-07", date(2014, 7, 3))
relativedelta(days=+4, bdays=+2)
# Take into account Canadian statutory holidays
>>> from holidays import Canada
>>> relativedelta('2014-07-07', '07/03/2014', holidays=Canada())
relativedelta(days=+4, bdays=+1)

# Get a list of the next 10 business days starting 2014-01-01
>>> from bdateutil import rrule, BDAILY
>>> list(rrule(BDAILY, count=10, dtstart=date(2014, 1, 1)))
# Take into account British Columbia, Canada statutory holidays
>>> list(rrule(BDAILY, count=10, dtstart=date(2014, 1, 1),
               holidays=Canada(prov='BC')))

Install

The latest stable version can always be installed or updated via pip:

$ pip install bdateutil

If the above fails, please use easy_install instead:

$ easy_install bdateutil

Documentation

This section will outline the additional functionality of bdateutil only. For full documentation on the features provided by python-dateutil please see its documentation at https://labix.org/python-dateutil.

bdateutil is 100% backwards compatible with python-dateutil. You can replace dateutil with bdateutil across your entire project and everything will continue to work the same but you will have access to the following additional features:

  1. A new, optional, keyword argument bdays is available when using relativedelta to add or remove time to a datetime object.
>>> date(2014, 1, 1) + relativedelta(bdays=+5)
date(2014, 1, 8)
  1. Use bdays=0 to ensure the date is a business day without explicitly checking in an if statement and modifying if not a bday
# Verbose
>>> dt = "2014-11-15"
>>> while not isbday(dt):
>>>     dt += relativedelta(days=1)
>>> print dt
datetime(2014, 11, 17, 0, 0)

# Nicer
>>> "2014-11-15" + relativedelta(bdays=0)
datetime(2014, 11, 17, 0, 0)

# Subtract the relativedelta to go back to the previous business day,
# if not a business day
>>> "2014-11-15" - relativedelta(bdays=0)
datetime(2014, 11, 14, 0, 0)

# If the date is already a business day, no changes
>>> "2014-11-13" + relativedelta(bdays=0)
datetime(2014, 11, 13, 0, 0)
  1. When passing two datetime arguments to relativedelta, the resulting relativedelta object will contain a bdays attribute with the number of business days between the datetime arguments.
>>> relativedelta(date(2014, 7, 7), date(2014, 7, 3))
relativedelta(days=+4, bdays=+2)
  1. Another new, optional, keyword argument holidays is available when using relativedelta to support the bdays feature. Without holidays business days are only calculated using weekdays. By passing a list of holidays a more accurate and useful business day calculation can be performed. The Python package holidays.py is installed as a requirement with bdateutil and that is the prefered way to generate holidays.
>>> from bdateutil import relativedelta
>>> from holidays import UnitedStates
>>> date(2014, 7, 3) + relativedelta(bdays=+2)
datetime.date(2014, 7, 7)
>>> date(2014, 7, 3) + relativedelta(bdays=+2, holidays=UnitedStates())
datetime.date(2014, 7, 8)

# Set relativedelta to always use holidays
>>> relativedelta.holidays = holidays.UnitedStates()
>>> date(2014, 7, 3) + relativedelta(bdays=+2)
datetime.date(2014, 7, 8)
  1. A new function isbday which returns True if the argument passed to it falls on a business day and False if it is a weekend or holiday. Option keyword argument holidays adds the ability to take into account a specific set of holidays.
>>> from bdateutil import isbday
>>> isbday(date(2014, 1, 1))
True
>>> isbday("2014-01-01")
True
>>> isbday("1/1/2014")
True
>>> isbday(1388577600)  # Unix timestamp = Jan 1, 2014
True

# Take into account U.S. statutory holidays
>>> import holidays
>>> isbday("2014-01-01", holidays=holidays.US())
False

# Set isbday to always take into account holidays
>>> isbday.holidays = holidays.US()
>>> isbday("2014-01-01")
False
  1. In addition to datetime and date types, relativedelta works with all strings/bytes regardless of encoding and integer/float timestamps. It does this by running all date/datetime parameters through the parse function which has been modified to accept many different types than strings, including date/datetime which will return without modifications. This allows you to call parse(dt) on an object regardless of type and ensure a datetime object is returned.
>>> parse(date(2014, 1, 1))
datetime.date(2014, 1, 1)
>>> parse(datetime(2014, 1, 1))
datetime.datetime(2014, 1, 1, 0, 0)
>>> parse("2014-01-01")
datetime.datetime(2014, 1, 1, 0, 0)
>>> parse("1/1/2014")
datetime.datetime(2014, 1, 1, 0, 0)
>>> parse(1388577600)
datetime.datetime(2014, 1, 1, 0, 0)

>>> relativedelta('2014-07-07', '2014-07-03')
relativedelta(days=+4, bdays=+2)

>>> 1388577600 + relativedelta(days=+2)
date(2014, 1, 3)
  1. The rrule feature has a new BDAILY option for use as the freq argument. This will create a generator which yields business days. Rrule also will now accept an optional holidays keyword argument which affects the BDAILY freq only. The existing dtstart and until arugments can now be passed as any type resembling a date/datetime.
# Get a list of the next 10 business days starting 2014-01-01
>>> from bdateutil import rrule, BDAILY
>>> list(rrule(BDAILY, count=10, dtstart=date(2014, 1, 1)))

# Get a list of all business days in January 2014, taking into account
# Canadian statutory holidays
>>> import holidays
>>> list(rrule(BDAILY, dtstart="2014-01-01", until="2014-01-31",
               holidays=holidays.Canada()))

# Add default set of holidays to rrule so you don't have to explicitly pass
# a holiday list each time you call rrule
>>> rrule.holidays = holidays.US()
# You can still pass a holidays argument to override the default setting
>>> list(rrule(BDAILY, dtstart="2014-01-01", until="2014-01-31",
               holidays=holidays.Canada()))
  1. Import shortcuts are available that make importing the bdateutil features a little easier than python-dateutil. However, importing from bdateutil using the longer method used by python-dateutil still works to remain 100% backwards compatibility.
>>> # Importing relativedelta from the original python-dateutil package
>>> from dateutil.relativedelta import relativedelta

>>> # This method works with bdateutil
>>> from bdateutil.relativedelta import relativedelta

>>> # bdateutil also provides an easier way
>>> from bdateutil import relativedelta
  1. Enhanced versions of the built-in datetime objects are available.
# Import from bdateutil instead of datetime
>>> from bdateutil import date, datetime, time

# Takes new, optional one-argument initialization which is parsed
# by bdateutil.parser
>>> date("2015-03-25")
datetime.date(2015, 3, 25)
>>> datetime(1042349200)
datetime.datetime(2003, 1, 12, 0, 26, 40)
>>> time("2:30 PM")
datetime.time(14, 30)

# time has a `now()` staticmethod similar to datetime
>>> time.now()
datetime.time(14, 52, 57, 984686)

# date.today(), datetime.now() and time.now() will accept relativedelta parameters
>>> date.today(days=+1) == date.today() + relativedelta(days=1)
>>> datetime.now(bdays=-45) == datetime.now() - relativedelta(bdays=45)
>>> time.now(hours=+1)
datetime.time(15, 52, 57, 984686)
# time.now(**kwargs) will return a datetime.time object if the resulting
# time is still in the current day or a datetime.datetime object if the
# result moves to another day
>>> time.now(days=+1) == datetime.now() + relativedelta(days=1)
# date.today(), datetime.now() and time.now() use the optional default
# holidays setting from relativedelta.holidays if they are set

# Pass 99 as the day to return the last day of the month
>>> date(2015, 2, 99)
date(2015, 2, 28)
>>> datetime(2015, 2, 99, 12, 0)
datetime(2015, 2, 28, 12, 0)

# New property `eomday` returns the last day of the month
>>> date(2015, 2, 15).eomday
date(2015, 2, 28)
>>> datetime(2015, 3, 25, 12, 34)
datetime(2015, 3, 31, 12, 34)

Development Version

The latest development version can be installed directly from GitHub:

$ pip install --upgrade https://github.com/ryanss/bdateutil/tarball/master

Running Tests

$ pip install flake8
$ flake8 bdateutil/*.py tests.py --ignore=F401,F403
$ python tests.py

Coverage

$ pip install coverage
$ coverage run --omit=*site-packages* tests.py
$ coverage report

Contributions

Issues and Pull Requests are always welcome.

License

Code and documentation are available according to the MIT License (see LICENSE).