encrypt-decrypt-web-api.js

async function encryptData(data, key) {
  const encodedData = new TextEncoder().encode(data);
  const iv = crypto.getRandomValues(new Uint8Array(12)); // Initialization vector
  const encryptedData = await crypto.subtle.encrypt(
    {
      name: "AES-GCM",
      iv: iv
    },
    key,
    encodedData
  );
  return { iv, encryptedData };
}

async function decryptData(encryptedData, key, iv) {
  const decryptedData = await crypto.subtle.decrypt(
    {
      name: "AES-GCM",
      iv: iv
    },
    key,
    encryptedData
  );
  return new TextDecoder().decode(decryptedData);
}

async function generateKey() {
  return await crypto.subtle.generateKey(
    {
      name: "AES-GCM",
      length: 256
    },
    true,
    ["encrypt", "decrypt"]
  );
}

// Example usage
(async () => {
  const key = await generateKey();
  const data = "Hello, World!";
  const { iv, encryptedData } = await encryptData(data, key);
  console.log("Encrypted Data:", new Uint8Array(encryptedData));

  const decryptedData = await decryptData(encryptedData, key, iv);
  console.log("Decrypted Data:", decryptedData);
})();