SymmetricKeyBuilder

A builder class for creating and importing symmetric keys. This class provides methods to configure key properties and generate or import symmetric keys.

Extends

• BaseCryptoClass

Accessors

algorithm

Set Signature

set algorithm(algorithm): void

Set the algorithm this key will be used with. Defaults to AES-256.

Throws

InvalidArgumentError If the algorithm is not supported.

Parameters

algorithm

SymmetricAlgorithm

The symmetric algorithm to use.

Returns

void

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bits

Set Signature

set bits(bits): void

Set the number of bits for the key. Defaults to 256 for AES.

Parameters

bits

number

The number of bits for the key.

Returns

void

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exportable

Set Signature

set exportable(exportable): void

Set whether the key is exportable.

Remarks

A key is NOT exportable unless explicitly set so.

Parameters

exportable

boolean

A boolean value indicating whether the key is exportable.

Returns

void

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purposes

Set Signature

set purposes(purposes): void

Set the purposes for which the key can be used.

Throws

InvalidArgumentError If any argument is not a valid purpose.

Parameters

purposes

KeyPurpose[]

An array of key purposes.

Returns

void

Methods

buildFromRaw()

buildFromRaw(rawKey): Promise<SymmetricKey>

Build a symmetric key from raw bytes.

Parameters

rawKey

ArrayBuffer

The actual bytes to be used as the symmetric key.

Returns

Promise<SymmetricKey>

A promise that resolves to the built symmetric key.

Remarks

The created key will inherit the properties (algorithm, purposes, exportability) set on this builder.

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buildGenerated()

buildGenerated(): Promise<SymmetricKey>

Build a new symmetric key based on the configured properties.

Returns

Promise<SymmetricKey>

A promise that resolves to the generated symmetric key.

Throws

InvalidArgumentError If the chosen key size is invalid.

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Last updated: Sep 30, 2025