How to quickly parse a parameterized HTTP header, such as Cookie or Signature, using Node.

main.js

const header = `keyid="bf9b523f-dd65-48a2-9512-fb66ba6c3714",
                algorithm="ed25519",
                signature="KhgcM+Ywv+DnQj4gE+DqWfNTM2TG5wfRuFQZ/zW48ValZuCHEu1h95Uyldqe7I85sS/QliCiRAF5QfW8ZN2vAw==",
                headers="(request-target) host date digest"`

// Parse the parameterized header into an object
const params = header.split(/,\s*/g)
  .map(keyvalue => keyvalue.match(/(?<key>[^=]+)="(?<value>[^"]+)"/i))
  .map(matches => matches.groups)
  .reduce(
    (obj, { key, value }) => (obj[key] = value, obj),
    {},
  )

console.log({ params })
// => {
//      params: {
//        keyid: 'bf9b523f-dd65-48a2-9512-fb66ba6c3714',
//        algorithm: 'ed25519',
//        signature: 'KhgcM+Ywv+DnQj4gE+DqWfNTM2TG5wfRuFQZ/zW48ValZuCHEu1h95Uyldqe7I85sS/QliCiRAF5QfW8ZN2vAw==',
//        headers: '(request-target) host date digest'
//      }
//    }