Important: This documentation is about an older version. It's relevant only to the release noted, many of the features and functions have been updated or replaced. Please view the current version.

Documentation

exportKey

Open source

exportKey

The exportKey() method takes a CryptoKey object as input and exports it in an external, portable format.

Note that for a key to be exportable, it must have been created with the extractable flag set to true.

Usage

exportKey(format, key)

Parameters

Name	Type	Description
`format`	`string`	Defines the data format in which the key should be exported. Depending on the algorithm and key type, the data format could vary. Currently supported formats are `raw`, `jwk`, `spki`, and `pkcs8`.
`key`	CryptoKey	The key to export.

Supported algorithms

AES-CBC	AES-CTR	AES-GCM	AES-KW	ECDH	ECDSA	HMAC	RSA-OAEP	RSASSA-PKCS1-v1_5	RSA-PSS
✅ AesCbcParams	✅ AesCtrParams	✅ AesGcmParams	❌	✅ EcdhKeyDeriveParams	✅ EcdsaParams	✅ HmacKeyGenParams	❌	❌	❌

Supported formats

ECDH and ECDSA algorithms have support for pkcs8, spki, raw and jwk formats.
AES-* and HMAC algorithms have currently support for raw and jwk formats.

Return Value

A Promise that resolves to a new ArrayBuffer or an JsonWebKey object/dictionary containing the key.

Throws

Type	Description
`InvalidAccessError`	Raised when trying to export a non-extractable key.
`NotSupportedError`	Raised when trying to export in an unknown format.
`TypeError`	Raised when trying to use an invalid format.

Example

import { crypto } from 'k6/experimental/webcrypto';

export default async function () {
  /**
   * Generate a symmetric key using the AES-CBC algorithm.
   */
  const generatedKey = await crypto.subtle.generateKey(
    {
      name: 'AES-CBC',
      length: '256',
    },
    true,
    ['encrypt', 'decrypt']
  );

  /**
   * Export the key in raw format.
   */
  const exportedKey = await crypto.subtle.exportKey('raw', generatedKey);

  /**
   * Reimport the key in raw format to verify its integrity.
   */
  const importedKey = await crypto.subtle.importKey('raw', exportedKey, 'AES-CBC', true, [
    'encrypt',
    'decrypt',
  ]);

  console.log(JSON.stringify(importedKey));
}