Authentication

Signing up

The userId to provide at signup should be a unique immutable string.

Ideally, it should be tied to the primary key (or ID) of the equivalent User object/table in your application database.

await e2esdkClient.signup(userId)

tip

User IDs don't have to be secret, autoincremented integers (represented as a string) are perfectly fine.

Logging in

await e2esdkClient.login(userId)

note

Wait a second, there's no password?

Access to e2esdk is authorized through enrolled devices.

tip

The device where you signed up is pre-enrolled. To login on other devices, you'll have to enroll and register them first.

Whoami

To know the identity of the currently logged in user:

const identity = e2esdkClient.publicIdentity

if (identity === null) {
  // Anonymous / not logged in
} else {
  const { userId } = identity
}

tip

When sharing keys, you might want to show the complete identity record of the recipient, to let the sender verify the recipient's identity via offline means.

Logging out

await e2esdkClient.logout()

Reacting to changes

The identityUpdated event lets you subscribe to authentication events:

const off = e2esdkClient.on('identityUpdated', identity => {
  if (identity === null) {
    console.info('Logged out')
  } else {
    console.info(`User ${identity.userId} logged in`)
  }
})

// Unsubscribe when you're done
off()

In React, you can use the useE2ESDKClientIdentity hook:

import React from 'react'
import { useE2ESDKClientIdentity } from '@socialgouv/e2esdk-react'

export const Profile: React.FC = () => {
  const identity = useE2ESDKClientIdentity()

  if (identity === null) {
    return <p>Logged out</p>
  }

  // A more "visual" way to represent this information
  // for users to easily eye-match would be preferable.
  const cryptographicIdentity = [
    identity.signaturePublicKey,
    identity.sharingPublicKey,
    identity.proof,
  ].join('.')

  return (
    <ul>
      <li>UserID: {identity.userId}</li>
      <li>Identity: {cryptographicIdentity}</li>
    </ul>
  )
}