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 and does not try
to execute the language detection again after a language is discarded.
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.
>>> 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 like below:
TIMEZONE
defaults to UTC. All dates, complete or relative, are assumed to be in UTC. When specified, resultant datetime
converts according to the supplied timezone:
>>> parse('January 12, 2012 10:00 PM')
datetime.datetime(2012, 1, 12, 22, 0)
>>> parse('January 12, 2012 10:00 PM', settings={'TIMEZONE': 'US/Eastern'})
datetime.datetime(2012, 1, 12, 17, 0)
PREFER_DAY_OF_MONTH
defaults to current
and can have first
and last
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.
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)
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'}