Skip to main content

A library for using the dateutil relativedeltas for calendar precision with aniso8601

Project description

RelativeTimeBuilder

aniso8601 builder for dateutil relativedeltas

Features

  • Provides RelativeTimeBuilder compatible with aniso8601
  • Returns dateutil relativedelta objects for durations

Installation

The recommended installation method is to use pip:

$ pip install relativetimebuilder

Alternatively, you can download the source (git repository hosted at Bitbucket) and install directly:

$ python setup.py install

Use

Parsing datetimes

To parse a typical ISO 8601 datetime string:

>>> import aniso8601
>>> from relativetimebuilder import RelativeTimeBuilder
>>> aniso8601.parse_datetime('1977-06-10T12:00:00', builder=RelativeTimeBuilder)
datetime.datetime(1977, 6, 10, 12, 0)

Alternative delimiters can be specified, for example, a space:

>>> aniso8601.parse_datetime('1977-06-10 12:00:00', delimiter=' ', builder=RelativeTimeBuilder)
datetime.datetime(1977, 6, 10, 12, 0)

Both UTC (Z) and UTC offsets for timezones are supported:

>>> aniso8601.parse_datetime('1977-06-10T12:00:00Z', builder=RelativeTimeBuilder)
datetime.datetime(1977, 6, 10, 12, 0, tzinfo=+0:00:00 UTC)
>>> aniso8601.parse_datetime('1979-06-05T08:00:00-08:00', builder=RelativeTimeBuilder)
datetime.datetime(1979, 6, 5, 8, 0, tzinfo=-8:00:00 UTC)

Leap seconds are explicitly not supported:

>>> aniso8601.parse_datetime('2018-03-06T23:59:60', builder=RelativeTimeBuilder)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/time.py", line 132, in parse_datetime
    return builder.build_datetime(datepart, timepart)
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/builders/python.py", line 181, in build_datetime
    cls._build_object(time))
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/builders/__init__.py", line 64, in _build_object
    ss=parsetuple[2], tz=parsetuple[3])
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/builders/python.py", line 141, in build_time
    raise LeapSecondError('Leap seconds are not supported.')
aniso8601.exceptions.LeapSecondError: Leap seconds are not supported.

Parsing dates

To parse a date represented in an ISO 8601 string:

>>> import aniso8601
>>> from relativetimebuilder import RelativeTimeBuilder
>>> aniso8601.parse_date('1984-04-23', builder=RelativeTimeBuilder)
datetime.date(1984, 4, 23)

Basic format is supported as well:

>>> aniso8601.parse_date('19840423', builder=RelativeTimeBuilder)
datetime.date(1984, 4, 23)

To parse a date using the ISO 8601 week date format:

>>> aniso8601.parse_date('1986-W38-1', builder=RelativeTimeBuilder)
datetime.date(1986, 9, 15)

To parse an ISO 8601 ordinal date:

>>> aniso8601.parse_date('1988-132', builder=RelativeTimeBuilder)
datetime.date(1988, 5, 11)

Parsing times

To parse a time formatted as an ISO 8601 string:

>>> import aniso8601
>>> from relativetimebuilder import RelativeTimeBuilder
>>> aniso8601.parse_time('11:31:14', builder=RelativeTimeBuilder)
datetime.time(11, 31, 14)

As with all of the above, basic format is supported:

>>> aniso8601.parse_time('113114', builder=RelativeTimeBuilder)
datetime.time(11, 31, 14)

A UTC offset can be specified for times:

>>> aniso8601.parse_time('17:18:19-02:30', builder=RelativeTimeBuilder)
datetime.time(17, 18, 19, tzinfo=-2:30:00 UTC)
>>> aniso8601.parse_time('171819Z', builder=RelativeTimeBuilder)
datetime.time(17, 18, 19, tzinfo=+0:00:00 UTC)

Reduced accuracy is supported:

>>> aniso8601.parse_time('21:42', builder=RelativeTimeBuilder)
datetime.time(21, 42)
>>> aniso8601.parse_time('22', builder=RelativeTimeBuilder)
datetime.time(22, 0)

A decimal fraction is always allowed on the lowest order element of an ISO 8601 formatted time:

>>> aniso8601.parse_time('22:33.5', builder=RelativeTimeBuilder)
datetime.time(22, 33, 30)
>>> aniso8601.parse_time('23.75', builder=RelativeTimeBuilder)
datetime.time(23, 45)

Leap seconds are explicitly not supported and attempting to parse one raises a LeapSecondError:

>>> aniso8601.parse_time('23:59:60', builder=RelativeTimeBuilder)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/time.py", line 117, in parse_time
    return _RESOLUTION_MAP[get_time_resolution(timestr)](timestr, tz, builder)
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/time.py", line 166, in _parse_second_time
    return builder.build_time(hh=hourstr, mm=minutestr, ss=secondstr, tz=tz)
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/builders/python.py", line 141, in build_time
    raise LeapSecondError('Leap seconds are not supported.')
aniso8601.exceptions.LeapSecondError: Leap seconds are not supported.

Parsing durations

Parsing durations returns relativedelta objects from dateutil for calendar level accuracy.

To parse a duration formatted as an ISO 8601 string:

>>> import aniso8601
>>> from relativetimebuilder import RelativeTimeBuilder
>>> aniso8601.parse_duration('P1Y2M3DT4H54M6S', builder=RelativeTimeBuilder)
relativedelta(years=+1, months=+2, days=+3, hours=+4, minutes=+54, seconds=+6)

Reduced accuracy is supported:

>>> aniso8601.parse_duration('P1Y', builder=RelativeTimeBuilder)
relativedelta(years=+1)

A decimal fraction is allowed on the lowest order element:

>>> aniso8601.parse_duration('P1YT3.5M', builder=RelativeTimeBuilder)
relativedelta(years=+1, minutes=+3.5)

The decimal fraction can be specified with a comma instead of a full-stop:

>>> aniso8601.parse_duration('P1YT3,5M', builder=RelativeTimeBuilder)
relativedelta(years=+1, minutes=+3.5)

Decimal fractions are not supported for years or months as calendar level accuracy would not be guaranteed:

>>> aniso8601.parse_duration('P1Y2.5M', builder=RelativeTimeBuilder)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/duration.py", line 30, in parse_duration
    return _parse_duration_prescribed(isodurationstr, builder)
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/duration.py", line 75, in _parse_duration_prescribed
    return _parse_duration_prescribed_notime(durationstr, builder)
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/duration.py", line 119, in _parse_duration_prescribed_notime
    PnW=weekstr, PnD=daystr)
  File "relativetimebuilder/__init__.py", line 24, in build_duration
    raise RelativeValueError('Fractional months and years are not '
relativetimebuilder.RelativeValueError: Fractional months and years are not defined for relative durations.
>>> aniso8601.parse_duration('P1.5Y', builder=RelativeTimeBuilder)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/duration.py", line 30, in parse_duration
    return _parse_duration_prescribed(isodurationstr, builder)
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/duration.py", line 75, in _parse_duration_prescribed
    return _parse_duration_prescribed_notime(durationstr, builder)
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/duration.py", line 119, in _parse_duration_prescribed_notime
    PnW=weekstr, PnD=daystr)
  File "relativetimebuilder/__init__.py", line 24, in build_duration
    raise RelativeValueError('Fractional months and years are not '
relativetimebuilder.RelativeValueError: Fractional months and years are not defined for relative durations.

Parsing a duration from a combined date and time is supported as well:

>>> aniso8601.parse_duration('P0001-01-02T01:30:5', builder=RelativeTimeBuilder)
relativedelta(years=+1, months=+1, days=+2, hours=+1, minutes=+30, seconds=+5)

Parsing intervals

Intervals are built using relativedelta objects from dateutil for calendar level accuracy.

To parse an interval specified by a start and end:

>>> import aniso8601
>>> from relativetimebuilder import RelativeTimeBuilder
>>> aniso8601.parse_interval('2007-03-01T13:00:00/2008-05-11T15:30:00', builder=RelativeTimeBuilder)
(datetime.datetime(2007, 3, 1, 13, 0), datetime.datetime(2008, 5, 11, 15, 30))

Intervals specified by a start time and a duration are supported:

>>> aniso8601.parse_interval('2007-03-01T13:00:00/P1Y2M10DT2H30M', builder=RelativeTimeBuilder)
(datetime.datetime(2007, 3, 1, 13, 0), datetime.datetime(2008, 5, 11, 15, 30))

A duration can also be specified by a duration and end time:

>>> aniso8601.parse_interval('P1M/1981-04-05', builder=RelativeTimeBuilder)
(datetime.date(1981, 4, 5), datetime.date(1981, 3, 5))

Notice that the result of the above parse is not in order from earliest to latest. If sorted intervals are required, simply use the sorted keyword as shown below:

>>> sorted(aniso8601.parse_interval('P1M/1981-04-05', builder=RelativeTimeBuilder))
[datetime.date(1981, 3, 5), datetime.date(1981, 4, 5)]

The end of an interval is returned as a datetime when required to maintain the resolution specified by a duration, even if the duration start is given as a date:

>>> aniso8601.parse_interval('2014-11-12/PT4H54M6.5S', builder=RelativeTimeBuilder)
(datetime.date(2014, 11, 12), datetime.datetime(2014, 11, 12, 4, 54, 6, 500000))
>>> aniso8601.parse_interval('2007-03-01/P1.5D', builder=RelativeTimeBuilder)
(datetime.date(2007, 3, 1), datetime.datetime(2007, 3, 2, 12, 0))

Repeating intervals are supported as well, and return a generator:

>>> aniso8601.parse_repeating_interval('R3/1981-04-05/P1D', builder=RelativeTimeBuilder)
<generator object _date_generator at 0x7f0862919fa0>
>>> list(aniso8601.parse_repeating_interval('R3/1981-04-05/P1D', builder=RelativeTimeBuilder))
[datetime.date(1981, 4, 5), datetime.date(1981, 4, 6), datetime.date(1981, 4, 7)]

Repeating intervals are allowed to go in the reverse direction:

>>> list(aniso8601.parse_repeating_interval('R2/PT1H2M/1980-03-05T01:01:00', builder=RelativeTimeBuilder))
[datetime.datetime(1980, 3, 5, 1, 1), datetime.datetime(1980, 3, 4, 23, 59)]

Unbounded intervals are also allowed (Python 2):

>>> result = aniso8601.parse_repeating_interval('R/PT1H2M/1980-03-05T01:01:00', builder=RelativeTimeBuilder)
>>> result.next()
datetime.datetime(1980, 3, 5, 1, 1)
>>> result.next()
datetime.datetime(1980, 3, 4, 23, 59)

or for Python 3:

>>> result = aniso8601.parse_repeating_interval('R/PT1H2M/1980-03-05T01:01:00', builder=RelativeTimeBuilder)
>>> next(result)
datetime.datetime(1980, 3, 5, 1, 1)
>>> next(result)
datetime.datetime(1980, 3, 4, 23, 59)

Intervals are calculated with calendar level accuracy:

>>> aniso8601.parse_interval('2003-01-27/P1M', builder=RelativeTimeBuilder)
(datetime.date(2003, 1, 27), datetime.date(2003, 2, 27))
>>> aniso8601.parse_interval('2003-01-31/P1M', builder=RelativeTimeBuilder)
(datetime.date(2003, 1, 31), datetime.date(2003, 2, 28))
>>> aniso8601.parse_interval('P1Y/2001-02-28', builder=RelativeTimeBuilder)
(datetime.date(2001, 2, 28), datetime.date(2000, 2, 28))

Fractional years and months do not make sense for relative intervals:

>>> aniso8601.parse_interval('P1.1Y/2001-02-28', builder=RelativeTimeBuilder)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/interval.py", line 40, in parse_interval
    intervaldelimiter, datetimedelimiter)
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/interval.py", line 98, in _parse_interval
    return builder.build_interval(end=enddate, duration=duration)
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/builders/python.py", line 311, in build_interval
    durationobject = cls._build_object(duration)
  File "/home/nielsenb/Jetfuse/aniso8601/aniso8601/aniso8601/builders/__init__.py", line 71, in _build_object
    TnS=parsetuple[6])
  File "relativetimebuilder/__init__.py", line 24, in build_duration
    raise RelativeValueError('Fractional months and years are not '
relativetimebuilder.RelativeValueError: Fractional months and years are not defined for relative durations.

Development

Setup

It is recommended to develop using a virtualenv.

Tests

Tests can be run using setuptools <https://setuptools.readthedocs.io/en/latest/setuptools.html>:

$ python setup.py test

Contributing

RelativeTimeBuilder is an open source project hosted on Bitbucket.

Any and all bugs are welcome on our issue tracker.

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Files for relativetimebuilder, version 2.0.1
Filename, size File type Python version Upload date Hashes
Filename, size relativetimebuilder-2.0.1-py2.py3-none-any.whl (10.1 kB) File type Wheel Python version py2.py3 Upload date Hashes View hashes
Filename, size relativetimebuilder-2.0.1.tar.gz (11.7 kB) File type Source Python version None Upload date Hashes View hashes

Supported by

Elastic Elastic Search Pingdom Pingdom Monitoring Google Google BigQuery Sentry Sentry Error logging AWS AWS Cloud computing DataDog DataDog Monitoring Fastly Fastly CDN DigiCert DigiCert EV certificate StatusPage StatusPage Status page