Settings¶
dateparser’s parsing behavior can be configured by supplying settings as a dictionary to settings argument in dateparser.parse()
or DateDataParser
constructor.
Note
From dateparser 1.0.0 when a setting with a wrong value is provided, a SettingValidationError
is raised.
All supported settings with their usage examples are given below:
Date Order¶
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_LOCALE_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, 2, 3, 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_LOCALE_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_LOCALE_DATE_ORDER': False})
datetime.datetime(2016, 2, 3, 0, 0) # MDY worked!
Handling Incomplete Dates¶
PREFER_DAY_OF_MONTH
: it comes handy when the date string is missing the day part. It defaults to current
and can be first
and last
denoting first and last day of months respectively as values:
>>> from dateparser import parse
>>> parse('December 2015') # default behavior
datetime.datetime(2015, 12, 16, 0, 0)
>>> parse('December 2015', settings={'PREFER_DAY_OF_MONTH': 'last'})
datetime.datetime(2015, 12, 31, 0, 0)
>>> parse('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('March')
datetime.datetime(2015, 3, 16, 0, 0)
>>> parse('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('14:30')
datetime.datetime(2015, 6, 16, 14, 30)
>>> parse('14:30', settings={'RELATIVE_BASE': datetime.datetime(2020, 1, 1)})
datetime.datetime(2020, 1, 1, 14, 30)
>>> parse('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('March', settings={'STRICT_PARSING': True})
None
REQUIRE_PARTS
: ensures results are dates that have all specified parts. It defaults to []
and can include day
, month
and/or year
.
For example, assuming current date is June 16, 2019:
>>> parse('2012') # default behavior
datetime.datetime(2012, 6, 16, 0, 0)
>>> parse('2012', settings={'REQUIRE_PARTS': ['month']})
None
>>> parse('March 2012', settings={'REQUIRE_PARTS': ['day']})
None
>>> parse('March 12, 2012', settings={'REQUIRE_PARTS': ['day']})
datetime.datetime(2012, 3, 12, 0, 0)
>>> parse('March 12, 2012', settings={'REQUIRE_PARTS': ['day', 'month', 'year']})
datetime.datetime(2012, 3, 12, 0, 0)
Language Detection¶
SKIP_TOKENS
: it 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)
DateData(date_obj=datetime.datetime(1981, 6, 27, 0, 0), period='day', locale='tr')
NORMALIZE
: applies unicode normalization (removing accents, diacritics…) when parsing the words. Defaults to True.
>>> dateparser.parse('4 decembre 2015', settings={'NORMALIZE': False})
# It doesn't work as the expected input should be '4 décembre 2015'
>>> dateparser.parse('4 decembre 2015', settings={'NORMALIZE': True})
datetime.datetime(2015, 12, 4, 0, 0)
Default Languages¶
DEFAULT_LANGUAGES
: It is a list
of language codes in ISO 639 that will be used as default
languages for parsing when language detection fails. eg. [“en”, “fr”]:
>>> from dateparser import parse
>>> parse('3 de marzo de 2020', settings={'DEFAULT_LANGUAGES': ["es"]})
Note
When using this setting, these languages will be tried after trying with the detected languages with no success. It is especially useful when using the ``detect_languages_function`.
Optional language detection¶
LANGUAGE_DETECTION_CONFIDENCE_THRESHOLD
: defaults to 0.5
. It is a float
of minimum required confidence for the custom language detection:
>>> from dateparser import parse
>>> parse('3 de marzo de 2020', settings={'LANGUAGE_DETECTION_CONFIDENCE_THRESHOLD': 0.5}, detect_languages_function=detect_languages)
Other settings¶
RETURN_TIME_AS_PERIOD
: returns time
as period in date object, if time component is present in date string.
Defaults to False
.
>>> ddp = DateDataParser(settings={'RETURN_TIME_AS_PERIOD': True})
>>> ddp.get_date_data('vr jan 24, 2014 12:49')
DateData(date_obj=datetime.datetime(2014, 1, 24, 12, 49), period='time', locale='nl')
PARSERS
: it is a list of names of parsers to try, allowing to customize which
parsers are tried against the input date string, and in which order they are
tried.
The following parsers exist:
'timestamp'
: If the input string starts with 10 digits, optionally followed by additional digits or a period (.
), those first 10 digits are interpreted as Unix time.'negative-timestamp'
:'timestamp'
for negative timestamps. For
example, parses-186454800000
as1964-02-03T23:00:00
.
'relative-time'
: Parses dates and times expressed in relation to the current date and time (e.g. “1 day ago”, “in 2 weeks”).'custom-formats'
: Parses dates that match one of the date formats in the list of thedate_formats
parameter ofdateparser.parse()
orDateDataParser.get_date_data
.'absolute-time'
: Parses dates and times expressed in absolute form (e.g. “May 4th”, “1991-05-17”). It takes into account settings such asDATE_ORDER
orPREFER_LOCALE_DATE_ORDER
.'no-spaces-time'
: Parses dates and times that consist in only digits or a combination of digits and non-digits where the first non-digit it’s a colon (e.g. “121994”, “11:052020”). It’s not included in the default parsers and it can produce false positives frequently.
dateparser.settings.default_parsers
contains the default value of
PARSERS
(the list above, in that order) and can be used to write code that
changes the parsers to try without skipping parsers that may be added to
Dateparser in the future. For example, to ignore relative times:
>>> from dateparser_data.settings import default_parsers
>>> parsers = [parser for parser in default_parsers if parser != 'relative-time']
>>> parse('today', settings={'PARSERS': parsers})