AIDC Toolkit

Appearance

AIDC Toolkit / Utility / Transformer

Abstract Class: Transformer ​

Defined in: transformer.ts:52

Transformer that transforms values in a numeric domain to values in a range equal to the domain or to another range defined by a callback function. In other words, the domain determines valid input values and, without a callback, the range of valid output values.

The concept is similar to format-preserving encryption, where input values within a specified domain (e.g., payment card numbers ranging from 8-19 digits) are transformed into values in the same domain, typically for storage in a database where the data type and length are already fixed and exfiltration of the data can have significant repercussions.

Two subclasses are supported directly by this class: IdentityTransformer (which operates based on a domain only) and EncryptionTransformer (which operates based on a domain and a tweak). If an application is expected to make repeated use of a transformer with the same domain and (optional) tweak and can't manage the transformer object, an in-memory cache is available via the get method. Properties in IdentityTransformer and EncryptionTransformer are read-only once constructed, so there is no issue with their shared use.

Extended by ​

Constructors ​

Constructor ​

new Transformer(domain): Transformer

Defined in: transformer.ts:69

Constructor.

Parameters ​

domain ​

Domain.

number | bigint

Returns ​

Transformer

Accessors ​

domain ​

Get Signature ​

get domain(): bigint

Defined in: transformer.ts:119

Get the domain.

Returns ​

bigint

Methods ​

get() ​

static get(domain, tweak?): Transformer

Defined in: transformer.ts:94

Get a transformer, constructing it if necessary. The type returned is IdentityTransformer if tweak is undefined, EncryptionTransformer if tweak is defined. Note that although an EncryptionTransformer with a zero tweak operates as an IdentityTransformer, EncryptionTransformer is still the type returned if a zero tweak is explicitly specified.

Parameters ​

domain ​

Domain.

number | bigint

tweak? ​

Tweak.

number | bigint

Returns ​

Transformer

IdentityTransformer if tweak is undefined, EncryptionTransformer if tweak is defined.

doForward() ​

abstract protected doForward(value): bigint

Defined in: transformer.ts:153

Do the work of transforming a value forward.

Parameters ​

value ​

bigint

Value.

Returns ​

bigint

Transformed value.

forward() ​

Call Signature ​

forward<TTransformerInput>(valueOrValues): TransformerOutput<TTransformerInput, bigint>

Defined in: transformer.ts:204

Transform value(s) forward.

Type Parameters ​
TTransformerInput ​

TTransformerInput extends TransformerInput<number | bigint>

Value(s) input type.

Parameters ​
valueOrValues ​

TTransformerInput

Value(s). If this is an instance of Sequence, the minimum and maximum values are validated prior to transformation. Otherwise, the individual value(s) is/are validated at the time of transformation.

Returns ​

TransformerOutput<TTransformerInput, bigint>

Transformed value(s).

Call Signature ​

forward<TTransformerInput, TOutput>(valueOrValues, transformerCallback): TransformerOutput<TTransformerInput, TOutput>

Defined in: transformer.ts:225

Transform value(s) forward, optionally applying a transformation.

Type Parameters ​
TTransformerInput ​

TTransformerInput extends TransformerInput<number | bigint>

Value(s) input type.

TOutput ​

TOutput

Transformation callback output type.

Parameters ​
valueOrValues ​

TTransformerInput

Value(s). If this is an instance of Sequence, the minimum and maximum values are validated prior to transformation. Otherwise, the individual value(s) is/are validated at the time of transformation.

transformerCallback ​

IndexedCallback<bigint, TOutput>

Called after each value is transformed to convert it to its final value.

Returns ​

TransformerOutput<TTransformerInput, TOutput>

Transformed value(s).

doReverse() ​

abstract protected doReverse(transformedValue): bigint

Defined in: transformer.ts:266

Do the work of transforming a value in reverse.

Parameters ​

transformedValue ​

bigint

Transformed value.

Returns ​

bigint

Value.

reverse() ​

reverse(transformedValue): bigint

Defined in: transformer.ts:277

Transform a value in reverse.

Parameters ​

transformedValue ​

Transformed value.

number | bigint

Returns ​

bigint

Value.