Settings — DateParser 1.4.1 documentation

# 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!

## Timezone Related Configurations

`TIMEZONE`: defaults to local timezone. When specified, resultant `datetime` is localized with the given timezone. Can be timezone abbreviation or any of tz database name as given here.

    >>> 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`: if `True` returns tz aware datetime objects in case timezone is detected in the date string.

    >>> parse('30 mins ago', settings={'RETURN_AS_TIMEZONE_AWARE': True})
    datetime.datetime(2017, 3, 13, 1, 43, 10, 243565, tzinfo=<DstTzInfo 'Asia/Karachi' PKT+5:00:00 STD>)

    >>> parse('12 Feb 2015 10:56 PM EST', settings={'RETURN_AS_TIMEZONE_AWARE': False})
    datetime.datetime(2015, 2, 12, 22, 56)

## 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_MONTH_OF_YEAR`: Similarly, another useful thing when the date string is missing the month part. It defaults to `current` and can be `first` and `last` denoting first and last month of year respectively as values:

    >>> from dateparser import parse
    >>> parse("2015") # default behavior
    datetime.datetime(2015, 3, 27, 0, 0)
    >>> parse("2015", settings={"PREFER_MONTH_OF_YEAR": "last"})
    datetime.datetime(2015, 12, 27, 0, 0)
    >>> parse("2015", settings={"PREFER_MONTH_OF_YEAR": "first"})
    datetime.datetime(2015, 1, 27, 0, 0)
    >>> parse("2015", settings={"PREFER_MONTH_OF_YEAR": "current"}) # it exactly behaves like default one
    datetime.datetime(2015, 3, 27, 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)

### `RETURN_TIME_SPAN`

default: `False`

When enabled, search_dates detects time span expressions (e.g., “past month”, “last week”) and returns start/end dates instead of single dates.

### `DEFAULT_START_OF_WEEK`

default: `'monday'`

Sets which day starts the week for time span calculations. Options: `'monday'`, `'sunday'`.

### `DEFAULT_DAYS_IN_MONTH`

default: `30`

Sets the number of days to use for “past month” and similar expressions in time span detection.

`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 `detect_languages_function`.

## Language Order

`USE_GIVEN_LANGUAGE_ORDER`: defaults to `False`. By default, the languages and locales passed through the `languages` and `locales` arguments are tried in the order of the most common languages, regardless of the order in which they are given. Set this to `True` to instead try them in the order in which they are given, which is useful when that order already reflects a preference (for example, the output of a language detector ordered by confidence):

    >>> import dateparser
    >>> dateparser.parse('11/12/2020', languages=['es', 'en'])
    datetime.datetime(2020, 11, 12, 0, 0)
    >>> dateparser.parse('11/12/2020', languages=['es', 'en'], settings={'USE_GIVEN_LANGUAGE_ORDER': True})
    datetime.datetime(2020, 12, 11, 0, 0)

It also applies to the languages given through the `DEFAULT_LANGUAGES` setting when they are used as a fallback.

Note

This setting only reorders the languages and locales that are given. If neither `languages` nor `locales` is provided, it has no effect and the default order is used:

    >>> dateparser.parse('11/12/2020', settings={'USE_GIVEN_LANGUAGE_ORDER': True})
    datetime.datetime(2020, 11, 12, 0, 0)

Note

This setting does not affect `dateparser.search.search_dates()`, which detects a single most likely language and normalizes the text before parsing, so it does not use the given language order to disambiguate values such as `11/12`.

## 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` as `1964-02-03T23:00:00`.

- `'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 the `date_formats` parameter of `dateparser.parse()` or `DateDataParser.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 as `DATE_ORDER` or `PREFER_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})

`CACHE_SIZE_LIMIT`: limits the size of caches, that store data for already processed dates. Default to `1000`, but you can set `0` for turning off the limit.