How do you implement email verification and password-reset flows securely in a Node.js application?

Both flows rely on generating a cryptographically random, single-use token, storing only its hash in the database alongside an expiration timestamp, and emailing the user a link containing the raw token -- when the link is clicked, the submitted token is hashed and compared against the stored hash, and the action (verifying the email, or allowing a password reset) is only permitted if the hash matches and the token hasn't expired or already been used, after which the token is immediately invalidated to prevent reuse.

const crypto = require('node:crypto');

async function generateResetToken(userId) {
  const rawToken = crypto.randomBytes(32).toString('hex');
  const hashedToken = crypto.createHash('sha256').update(rawToken).digest('hex');
  await db.passwordResets.create({ userId, hashedToken, expiresAt: Date.now() + 3600000 });
  return rawToken; // only the raw token is emailed, never stored
}