Filters Dates

Dates

Filter

This filter identifies dates such as May 22, 2014 in text. The supported date formats are:

Format	Example
yyyy-MM-d	2020-05-10
MM-dd-yyyy	05-10-2020
M-d-y	5-10-2020
MMM dd	May 5 or May 05
MMMM dd, yyyy	May 5, 2020 or May 5 2020

Required Parameters

This filter has no required parameters.

Optional Parameters

Parameter	Description	Default Value
dateFilterStrategies	A list of filter strategies.	None
enabled	When set to false, the filter will be disabled and not applied	true
ignored	A list of terms to be ignored by the filter.	None
onlyValidDates	When set to true, only valid dates will be filtered.	false

Filter Strategies {id="filter-strategies"}

The filter may have zero or more filter strategies. When no filter strategy is given the default strategy of REDACT is used. When multiple filter strategies are given the filter strategies will be applied in order as they are listed. See Filter Strategies for details.

Strategy	Description
REDACT	Replace the sensitive text with a placeholder.
RANDOM_REPLACE	Replace the sensitive text with a similar, random value.
STATIC_REPLACE	Replace the sensitive text with a given value.
CRYPTO_REPLACE	Replace the sensitive text with its encrypted value.
HASH_SHA256_REPLACE	Replace the sensitive text with its SHA256 hash value.
SHIFT	Shift the date by a number of months, days, and/or years.
SHIFTRANDOM	Shift the data by a random number of months, days, and years.
RELATIVE	Replace the date by a words relative to the date.

Filter Strategy Options

The following filter strategy options are available for the RELATIVE filter strategy.

	Description	Default Value
futureDates	When true, future dates are replaced by relative words. When false, future dates are redacted.	false

The following filter strategy options are available for the SHIFT filter strategy.

Option	Description	Default Value
shiftDays	The number of days to shift the date. Can be a negative or positive integer. Defaults to 0 if not specified.	0
shiftMinutes	The number of minutes to shift the date. Can be a negative or positive integer. Defaults to 0 if not specified.	0
shiftYears	The number of years to shift the date. Can be a negative or positive integer. Defaults to 0 if not specified.	0

Conditions {id="conditions"}

Each filter strategy may have one condition. See Conditions for details.

Conditional	Description	Operators
TOKEN	Compares the value of the sensitive text.	== , !=
TOKEN	Compares the sensitive text to some category, e.g. birthdate.	is
CONTEXT	Compares the filtering context.	== , !=
CONFIDENCE	Compares the confidence in the sensitive text against a threshold value.	< , <=, > , >=, ==, !=

Differentiating Between Dates and Birth Dates

In some cases it may be necessary to redact birth dates and dates differently. Using conditions it is possible to determine if an identified date is a birth date. The conditional token is birthdate will determine if the identified date (token) is a birth date by analyzing the content surrounding the date.

Example Policy to Redact Dates

The following policy redacts dates.

{
   "name": "dates-example",
   "identifiers": {
      "date": {
         "onlyValidDates": false,
         "dateFilterStrategies": [
            {
               "strategy": "REDACT",
               "redactionFormat": "{{{REDACTED-%t}}}"
            }
         ]
      }
   }
}

Example Policy to Shift Dates

The following policy to shift dates forward by 2 days and 4 months.

{
   "name": "dates-example",
   "identifiers": {
      "date": {
         "onlyValidDates": false,
         "dateFilterStrategies": [
            {
               "strategy": "SHIFT",
               "shiftDays": 2,
               "shiftMonths": 4,
               "shiftYears": 0
            }
         ]
      }
   }
}