Redaction Strategies

Strategies receive a detected value and detector name. Detectors decide what the sensitive span is; strategies decide what replaces it.

mask
hash
tokenise
drop
Pii::redact($text);
// [REDACTED]

$strategy = app(\Padosoft\PiiRedactor\Strategies\RedactionStrategyFactory::class)->make('hash');
Pii::redact($text, $strategy);
// [hash:...]

$strategy = app(\Padosoft\PiiRedactor\Strategies\RedactionStrategyFactory::class)->make('tokenise');
Pii::redact($text, $strategy);
// [tok:email:...]

$strategy = app(\Padosoft\PiiRedactor\Strategies\RedactionStrategyFactory::class)->make('drop');
Pii::redact($text, $strategy);
// sensitive span removed

Strategy choice

Strategy Use when Risk
mask Human-facing logs and support views Loses joinability
hash Pseudonymous joins across records Salt rotation breaks joins
tokenise Forensic recovery is required Token store becomes sensitive infrastructure
drop Downstream cannot receive placeholders Text may become harder to read

The birthday-bound intuition for truncated identifiers is approximately:

p≈n22mp \approx \frac{n^2}{2m}

where n is the number of unique values and m is the hash namespace size.