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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.

Open source

sign

The sign() operation generates a digital signature of the provided data, using the given CryptoKey object.

Usage

sign(algorithm, key, data)

Parameters

NameTypeDescription
algorithmstring or object with a single name string propertyThe signature algorithm to use. Currently supported: HMAC.
keyCryptoKeyThe key to use for signing.
dataArrayBuffer, TypedArray, or DataViewThe data to be signed.

Return Value

A Promise that resolves with the signature as an ArrayBuffer.

Throws

TypeDescription
InvalidAccessErrorRaised when the signing key either does not support signing operation, or is incompatible with the selected algorithm.

Example

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

export default async function () {
  const generatedKey = await crypto.subtle.generateKey(
    {
      name: 'HMAC',
      hash: { name: 'SHA-1' },
    },
    true,
    ['sign', 'verify']
  );

  const data = string2ArrayBuffer('Hello World');

  /**
   * Signes the encoded data with the provided key using the HMAC algorithm
   * the returned signature can be verified using the verify method.
   */
  const signature = await crypto.subtle.sign('HMAC', generatedKey, data);

  /**
   * Verifies the signature of the encoded data with the provided key using the HMAC algorithm.
   */
  const verified = await crypto.subtle.verify('HMAC', generatedKey, signature, data);

  console.log('verified: ', verified);
}

function string2ArrayBuffer(str) {
  const buf = new ArrayBuffer(str.length * 2); // 2 bytes for each char
  const bufView = new Uint16Array(buf);
  for (let i = 0, strLen = str.length; i < strLen; i++) {
    bufView[i] = str.charCodeAt(i);
  }
  return buf;
}