Add user to the database

You probably want to know how to add a user to your database after they authenticate, so you can do things with them in your app after they sign in.
If you already have your own logic set up for adding users to your database, then you might not need this guide, but we still recommend reading through it.
Want to skip to the real code example? Click here.
Core Concepts
There are typically two separate steps to a user signing in to an app:
Authenticate: Let the user verify their identity and securely enter your app (this is what Doorman does).
Add user to database: Most apps want to collect information from users after they authenticate, like a name, profile picture, etc. In order to do so, once a user has authenticated, you will probably do the following steps:
Make a request to your database, and check if the user exists/has completed onboarding.
If the user exists, send them into your app.
If the user does not exist, send them to an onboarding flow.
Visualization
How to add user to DB
Adding your user to the database with Doorman is easy. It just requires a few extra steps after the initial set up.
Oversimplified example
This is an oversimplified version of the logic we want to create:
if (user) {
  // user is authenticated
  const uid = user.uid // user id
  
  // check DB to see if the user exists
  const { exists } = await doesUserExistInDb(uid)
  
  // set state based on the DB value
  setUserExists(exists)
} else {
  // user is not signed in, reset the state
  setUserExists(false)
}
In a component, this oversimplified code might look like this:
// this screen shows up after the user has authenticated
​
export default function App() {
  const [checkingIfExists, setCheckingIfExists] = useState(false)
  const [userExists, setUserExists] = useState(false)
  
  const onAuthStateChanged = async (user) => {
    if (user) {
      // user is authenticated
      
      const uid = user.uid // user id
      
      // show loading indicator
      setCheckingIfExists(true)
      
      // check DB to see if the user exists
      const { exists } = await doesUserExistInDb(uid)
      
      // set state based on the DB value
      setUserExists(exists)
      
      // set loading state to false
      setCheckingIfExists(false)
    } else {
      // user is not signed in, reset the state
      setUserExists(false)
      setCheckingIfExists(false)
    }
  }
  
  // if the DB call is loading
  if (checkingIfExists) return <LoadingScreen />
  
  // if the user doesn't exist
  if (!userExists) return <OnboardingStack />
  
  // user exists! render the app
  return <App />
}
This screen would show up after your user has authenticated.
Real code example
Let's continue to the next page to see how to implement this in real code with Doorman:
User to DB code example
/concepts/add-user-to-the-database/user-in-db-code-example
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Accessing the current user
User to DB code example
Last updated 4 months ago