Identifier

Filter

This filter identifies custom text based on a given regular expression.

The Identifier filter accepts a list of regular expression-based identifiers. See the policy at the bottom of this page for an example.

Note that backslashes in the regular expression will need to be escaped for the policy to be valid JSON.

Required Parameters

This filter has no required parameters.

Optional Parameters

Parameter	Description	Default Value
`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
`caseSensitive`	When set to true, the regular expression will be case sensitive.	`true`
`classification`	Used to apply an arbitrary label to the identifier, such as "patient-id", or "account-number."	`"custom-identifier"`
`pattern`	A regular expression for the identifier. Note that backslashes will need to be escaped.	`\b[A-Z0-9_-]{4,}\b`

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 as they are listed. See Filter Strategiesfor 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.
`LAST_4`	Replace the sensitive text with just the last four characters of the text.

Conditions

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

Conditional	Description	Operators
`TOKEN`	Compares the value of the sensitive text.	`==`, `!=`
`CONTEXT`	Compares the filtering context.	`==`, `!=`
`CONFIDENCE`	Compares the confidence in the sensitive text against a threshold value.	`<`, `<=`, `>`, `>=`, `==`, `!=`
`CLASSIFICATION`	Compares the classification of the sensitive text.	`==`, `!=`

Example Policy

{
  "name": "default",
  "identifiers": {
    "identifiers": [
      {
        "pattern": "[A-Z]{9}",
        "caseSensitive": false,
        "classification": "custom-identifier",
        "enabled": true,
        "identifierFilterStrategies": [
          {
            "strategy": "REDACT",
            "redactionFormat": "{{{REDACTED-%t}}}"
          }
        ]        
      }
    ]
  }
}

Last modified: 17 November 2023