dateparser – python parser for human readable dates¶
dateparser provides modules to easily parse localized dates in almost any string formats commonly found on web pages.
Documentation¶
Documentation is built automatically and can be found on Read the Docs.
Features¶
- Generic parsing of dates in English, Spanish, Dutch, Russian and over 20 other languages plus numerous formats in a language agnostic fashion.
- Generic parsing of relative dates like:
'1 min ago'
,'2 weeks ago'
,'3 months, 1 week and 1 day ago'
,'in 2 days'
,'tomorrow'
. - Generic parsing of dates with time zones abbreviations or UTC offsets like:
'August 14, 2015 EST'
,'July 4, 2013 PST'
,'21 July 2013 10:15 pm +0500'
. - Support for non-Gregorian calendar systems. See Supported Calendars.
- Extensive test coverage.
Usage¶
The most straightforward way is to use the dateparser.parse function, that wraps around most of the functionality in the module.
-
dateparser.
parse
(*args, **kwargs)[source]¶ Parse date and time from given date string.
Parameters: - date_string (str|unicode) – A string representing date and/or time in a recognizably valid format.
- date_formats (list) – A list of format strings using directives as given here. The parser applies formats one by one, taking into account the detected languages.
- languages (list) – A list of two letters language codes.e.g. [‘en’, ‘es’]. If languages are given, it will not attempt to detect the language.
- settings (dict) – Configure customized behavior using settings defined in
dateparser.conf.Settings
.
Returns: Returns
datetime
representing parsed date if successful, else returns NoneReturn type: Raises: ValueError - Unknown Language
Popular Formats¶
>>> import dateparser
>>> dateparser.parse('12/12/12')
datetime.datetime(2012, 12, 12, 0, 0)
>>> dateparser.parse(u'Fri, 12 Dec 2014 10:55:50')
datetime.datetime(2014, 12, 12, 10, 55, 50)
>>> dateparser.parse(u'Martes 21 de Octubre de 2014') # Spanish (Tuesday 21 October 2014)
datetime.datetime(2014, 10, 21, 0, 0)
>>> dateparser.parse(u'Le 11 Décembre 2014 à 09:00') # French (11 December 2014 at 09:00)
datetime.datetime(2014, 12, 11, 9, 0)
>>> dateparser.parse(u'13 января 2015 г. в 13:34') # Russian (13 January 2015 at 13:34)
datetime.datetime(2015, 1, 13, 13, 34)
>>> dateparser.parse(u'1 เดือนตุลาคม 2005, 1:00 AM') # Thai (1 October 2005, 1:00 AM)
datetime.datetime(2005, 10, 1, 1, 0)
This will try to parse a date from the given string, attempting to detect the language each time.
You can specify the language(s), if known, using languages
argument. In this case, given languages are used and language detection is skipped:
>>> dateparser.parse('2015, Ago 15, 1:08 pm', languages=['pt', 'es'])
datetime.datetime(2015, 8, 15, 13, 8)
If you know the possible formats of the dates, you can
use the date_formats
argument:
>>> dateparser.parse(u'22 Décembre 2010', date_formats=['%d %B %Y'])
datetime.datetime(2010, 12, 22, 0, 0)
Relative Dates¶
>>> parse('1 hour ago')
datetime.datetime(2015, 5, 31, 23, 0)
>>> parse(u'Il ya 2 heures') # French (2 hours ago)
datetime.datetime(2015, 5, 31, 22, 0)
>>> parse(u'1 anno 2 mesi') # Italian (1 year 2 months)
datetime.datetime(2014, 4, 1, 0, 0)
>>> parse(u'yaklaşık 23 saat önce') # Turkish (23 hours ago)
datetime.datetime(2015, 5, 31, 1, 0)
>>> parse(u'Hace una semana') # Spanish (a week ago)
datetime.datetime(2015, 5, 25, 0, 0)
>>> parse(u'2小时前') # Chinese (2 hours ago)
datetime.datetime(2015, 5, 31, 22, 0)
Note
Testing above code might return different values for you depending on your environment’s current date and time.
Note
Support for relative dates in future needs a lot of improvement, we look forward to community’s contribution to get better on that part. See `Contributing`_.
OOTB Language Based Date Order Preference¶
>>> # parsing ambiguous date
>>> parse('02-03-2016') # assumes english language, uses MDY date order
datetime.datetime(2016, 3, 2, 0, 0)
>>> parse('le 02-03-2016') # detects french, uses DMY date order
datetime.datetime(2016, 3, 2, 0, 0)
Note
Ordering is not locale based, that’s why do not expect DMY order for UK/Australia English. You can specify date order in that case as follows usings Settings:
>>> parse('18-12-15 06:00', settings={'DATE_ORDER': 'DMY'})
datetime.datetime(2015, 12, 18, 6, 0)
For more on date order, please look at Settings.
Timezone and UTC Offset¶
dateparser automatically detects the timezone if given in the date string. If date has no timezone name/abbreviation or offset, you can still specify it using TIMEZONE setting.
>>> parse('January 12, 2012 10:00 PM', settings={'TIMEZONE': 'US/Eastern'})
datetime.datetime(2012, 1, 12, 22, 0)
You can also convert from one time zone to another using TO_TIMEZONE setting.
>>> parse('10:00 am', settings={'TO_TIMEZONE': 'EDT', 'TIMEZONE': 'EST'})
datetime.datetime(2016, 9, 25, 11, 0)
>>> parse('10:00 am EST', settings={'TO_TIMEZONE': 'EDT'})
datetime.datetime(2016, 9, 25, 11, 0)
Support for tzaware objects:
>>> parse('12 Feb 2015 10:56 PM EST', settings={'RETURN_AS_TIMEZONE_AWARE': True})
datetime.datetime(2015, 2, 12, 22, 56, tzinfo=<StaticTzInfo 'EST'>)
For more on timezones, please look at Settings.
Incomplete Dates¶
>>> from dateparser import parse
>>> parse(u'December 2015') # default behavior
datetime.datetime(2015, 12, 16, 0, 0)
>>> parse(u'December 2015', settings={'PREFER_DAY_OF_MONTH': 'last'})
datetime.datetime(2015, 12, 31, 0, 0)
>>> parse(u'December 2015', settings={'PREFER_DAY_OF_MONTH': 'first'})
datetime.datetime(2015, 12, 1, 0, 0)
>>> parse(u'March')
datetime.datetime(2015, 3, 16, 0, 0)
>>> parse(u'March', settings={'PREFER_DATES_FROM': 'future'})
datetime.datetime(2016, 3, 16, 0, 0)
>>> # parsing with preference set for 'past'
>>> parse('August', settings={'PREFER_DATES_FROM': 'past'})
datetime.datetime(2015, 8, 15, 0, 0)
You can also ignore parsing incomplete dates altogether by setting STRICT_PARSING flag as follows:
>>> parse(u'December 2015', settings={'STRICT_PARSING': True})
None
For more on handling incomplete dates, please look at Settings.
Dependencies¶
dateparser relies on following libraries in some ways:
- dateutil‘s module
relativedelta
for its freshness parser.- ruamel.yaml for reading language and configuration files.
- jdatetime to convert Jalali dates to Gregorian.
- umalqurra to convert Hijri dates to Gregorian.
- tzlocal to reliably get local timezone.
Supported languages¶
- Arabic
- Belarusian
- Chinese
- Czech
- Danish
- Dutch
- English
- Filipino/Tagalog
- Finnish
- French
- Hebrew
- Hungarian
- German
- Indonesian
- Italian
- Japanese
- Persian
- Polish
- Portuguese
- Romanian
- Russian
- Spanish
- Thai
- Turkish
- Ukrainian
- Vietnamese
Supported Calendars¶
Gregorian calendar.
Persian Jalali calendar. For more information, refer to Persian Jalali Calendar.
Hijri/Islamic Calendar. For more information, refer to Hijri Calendar.
>>> from dateparser.calendars.jalali import JalaliCalendar >>> JalaliCalendar(u'جمعه سی ام اسفند ۱۳۸۷').get_date() {'date_obj': datetime.datetime(2009, 3, 20, 0, 0), 'period': 'day'}
>>> from dateparser.calendars.hijri import HijriCalendar >>> HijriCalendar(u'17-01-1437 هـ 08:30 مساءً').get_date() {'date_obj': datetime.datetime(2015, 10, 30, 20, 30), 'period': 'day'}
Note
HijriCalendar has some limitations with Python 3.
Note
For Finnish language, please specify settings={‘SKIP_TOKENS’: []} to correctly parse freshness dates.
Using DateDataParser¶
dateparser.parse()
uses a default parser which tries to detect language
every time it is called and is not the most efficient way while parsing dates
from the same source.
DateDataParser
provides an alternate and efficient way
to control language detection behavior.
The instance of DateDataParser
reduces the number
of applicable languages, until only one or no language is left. It
assumes the previously detected language for all the subsequent dates supplied.
This class wraps around the core dateparser
functionality, and by default
assumes that all of the dates fed to it are in the same language.
-
class
dateparser.date.
DateDataParser
(*args, **kwargs)[source]¶ Class which handles language detection, translation and subsequent generic parsing of string representing date and/or time.
Parameters: - languages (list) – A list of two letters language codes, e.g. [‘en’, ‘es’]. If languages are given, it will not attempt to detect the language.
- allow_redetect_language (bool) – Enables/disables language re-detection.
- settings (dict) – Configure customized behavior using settings defined in
dateparser.conf.Settings
.
Returns: A parser instance
Raises: ValueError - Unknown Language, TypeError - Languages argument must be a list
-
get_date_data
(date_string, date_formats=None)[source]¶ Parse string representing date and/or time in recognizable localized formats. Supports parsing multiple languages and timezones.
Parameters: Returns: a dict mapping keys to
datetime.datetime
object and period. For example: {‘date_obj’: datetime.datetime(2015, 6, 1, 0, 0), ‘period’: u’day’}Raises: ValueError - Unknown Language
Note
Period values can be a ‘day’ (default), ‘week’, ‘month’, ‘year’.
Period represents the granularity of date parsed from the given string.
In the example below, since no day information is present, the day is assumed to be current day
16
from current date (which is June 16, 2015, at the moment of writing this). Hence, the level of precision ismonth
:>>> DateDataParser().get_date_data(u'March 2015') {'date_obj': datetime.datetime(2015, 3, 16, 0, 0), 'period': u'month'}
Similarly, for date strings with no day and month information present, level of precision is
year
and day16
and month6
are from current_date.>>> DateDataParser().get_date_data(u'2014') {'date_obj': datetime.datetime(2014, 6, 16, 0, 0), 'period': u'year'}
Dates with time zone indications or UTC offsets are returned in UTC time unless specified using Settings.
>>> DateDataParser().get_date_data(u'23 March 2000, 1:21 PM CET') {'date_obj': datetime.datetime(2000, 3, 23, 14, 21), 'period': 'day'}
Warning
It fails to parse English dates in the example below, because Spanish was detected and stored with the ddp
instance:
>>> ddp.get_date_data('11 August 2012')
{'date_obj': None, 'period': 'day'}
dateparser.date.DateDataParser
can also be initialized with known languages:
>>> ddp = DateDataParser(languages=['de', 'nl'])
>>> ddp.get_date_data(u'vr jan 24, 2014 12:49')
{'date_obj': datetime.datetime(2014, 1, 24, 12, 49), 'period': u'day'}
>>> ddp.get_date_data(u'18.10.14 um 22:56 Uhr')
{'date_obj': datetime.datetime(2014, 10, 18, 22, 56), 'period': u'day'}
Settings¶
dateparser
‘s parsing behavior can be configured by supplying settings as a dictionary to settings argument in dateparser.parse or DateDataParser
constructor.
All supported settings with their usage examples are given below:
DATE_ORDER
specifies the order in which date components year, month and day are expected while parsing ambiguous dates. It defaults to MDY which translates to month first, day second and year last order. Characters M, D or Y can be shuffled to meet required order. For example, DMY specifies day first, month second and year last order:
>>> parse('15-12-18 06:00') # assumes default order: MDY
datetime.datetime(2018, 12, 15, 6, 0) # since 15 is not a valid value for Month, it is swapped with Day's
>>> parse('15-12-18 06:00', settings={'DATE_ORDER': 'YMD'})
datetime.datetime(2015, 12, 18, 6, 0)
PREFER_LANGUAGE_DATE_ORDER
defaults to True. Most languages have a default DATE_ORDER specified for them. For example, for French it is DMY:
>>> # parsing ambiguous date
>>> parse('02-03-2016') # assumes english language, uses MDY date order
datetime.datetime(2016, 3, 2, 0, 0)
>>> parse('le 02-03-2016') # detects french, hence, uses DMY date order
datetime.datetime(2016, 3, 2, 0, 0)
Note
There’s no language level default DATE_ORDER associated with en language. That’s why it assumes MDY which is :obj:settings <dateparser.conf.settings>
default. If the language has a default DATE_ORDER associated, supplying custom date order will not be applied unless we set PREFER_LANGUAGE_DATE_ORDER to False:
>>> parse('le 02-03-2016', settings={'DATE_ORDER': 'MDY'})
datetime.datetime(2016, 3, 2, 0, 0) # MDY didn't apply
>>> parse('le 02-03-2016', settings={'DATE_ORDER': 'MDY', 'PREFER_LANGUAGE_DATE_ORDER': False})
datetime.datetime(2016, 2, 3, 0, 0) # MDY worked!
TIMEZONE
defaults to local timezone. When specified, resultant datetime
is localized with the given timezone.
>>> parse('January 12, 2012 10:00 PM', settings={'TIMEZONE': 'US/Eastern'})
datetime.datetime(2012, 1, 12, 22, 0)
TO_TIMEZONE
defaults to None. When specified, resultant datetime
converts according to the supplied timezone:
>>> settings = {'TIMEZONE': 'UTC', 'TO_TIMEZONE': 'US/Eastern'}
>>> parse('January 12, 2012 10:00 PM', settings=settings)
datetime.datetime(2012, 1, 12, 17, 0)
RETURN_AS_TIMEZONE_AWARE
is a flag to turn on timezone aware dates if timezone is detected or specified.:
>>> parse('12 Feb 2015 10:56 PM EST', settings={'RETURN_AS_TIMEZONE_AWARE': True}) datetime.datetime(2015, 2, 13, 3, 56, tzinfo=<StaticTzInfo 'UTC'>)>>> parse('12 Feb 2015 10:56 PM EST', settings={'RETURN_AS_TIMEZONE_AWARE': True, 'TIMEZONE': 'EST'}) datetime.datetime(2015, 2, 12, 22, 56, tzinfo=<StaticTzInfo 'EST'>)if TIMEZONE is set to None and RETURN_AS_TIMEZONE_AWARE to True, a tz aware date will only be returned if timezone is detected in the string.
>>> parse('12 Feb 2015 10:56 PM', settings={'RETURN_AS_TIMEZONE_AWARE': True, 'TIMEZONE': None}) datetime.datetime(2015, 2, 12, 22, 56)>>> parse('12 Feb 2015 10:56 PM EST', settings={'RETURN_AS_TIMEZONE_AWARE': True, 'TIMEZONE': None}) datetime.datetime(2015, 2, 12, 22, 56, tzinfo=<StaticTzInfo 'EST'>)
PREFER_DAY_OF_MONTH
This option comes handy when the date string is missing the day part. It defaults to current
and can have first
and last
denoting first and last day of months respectively as values:
>>> from dateparser import parse
>>> parse(u'December 2015') # default behavior
datetime.datetime(2015, 12, 16, 0, 0)
>>> parse(u'December 2015', settings={'PREFER_DAY_OF_MONTH': 'last'})
datetime.datetime(2015, 12, 31, 0, 0)
>>> parse(u'December 2015', settings={'PREFER_DAY_OF_MONTH': 'first'})
datetime.datetime(2015, 12, 1, 0, 0)
PREFER_DATES_FROM
defaults to current_period and can have past and future as values.
If date string is missing some part, this option ensures consistent results depending on the past or future preference, for example, assuming current date is June 16, 2015:
>>> from dateparser import parse
>>> parse(u'March')
datetime.datetime(2015, 3, 16, 0, 0)
>>> parse(u'March', settings={'PREFER_DATES_FROM': 'future'})
datetime.datetime(2016, 3, 16, 0, 0)
>>> # parsing with preference set for 'past'
>>> parse('August', settings={'PREFER_DATES_FROM': 'past'})
datetime.datetime(2015, 8, 15, 0, 0)
RELATIVE_BASE
allows setting the base datetime to use for interpreting partial or relative date strings.
Defaults to the current date and time.
For example, assuming current date is June 16, 2015:
>>> from dateparser import parse
>>> parse(u'14:30')
datetime.datetime(2015, 3, 16, 14, 30)
>>> parse(u'14:30', settings={'RELATIVE_BASE': datetime.datetime(2020, 1, 1)})
datetime.datetime(2020, 1, 1, 14, 30)
>>> parse(u'tomorrow', settings={'RELATIVE_BASE': datetime.datetime(2020, 1, 1)})
datetime.datetime(2020, 1, 2, 0, 0)
STRICT_PARSING
defaults to False.
When set to True if missing any of day, month or year parts, it does not return any result altogether.:
>>> parse(u'March', settings={'STRICT_PARSING': True})
None
SKIP_TOKENS
is a list
of tokens to discard while detecting language. Defaults to ['t']
which skips T in iso format datetime string .e.g. 2015-05-02T10:20:19+0000
.:
>>> from dateparser.date import DateDataParser
>>> DateDataParser(settings={'SKIP_TOKENS': ['de']}).get_date_data(u'27 Haziran 1981 de') # Turkish (at 27 June 1981)
{'date_obj': datetime.datetime(1981, 6, 27, 0, 0), 'period': 'day'}