Hasura Firebase Token Refresh

YourClient.js

firebase.auth().onAuthStateChanged((firebaseUser) => {
  if (firebaseUser) {
    return firebaseUser.getIdToken().then((token) => firebase.auth().currentUser.getIdTokenResult()
      .then((result) => {
        if (result.claims['https://hasura.io/jwt/claims']) {
          return token
        }
        const endpoint = 'https://xxx.cloudfunctions.net/refreshToken'
        return fetch(`${endpoint}?uid=${firebaseUser.uid}`).then((res) => {
          if (res.status === 200) {
            return firebaseUser.getIdToken(true)
          }
          return res.json().then((e) => { throw e })
        })
      })).then((validToken) => {
      // Store Token / Or create Apollo with your new token!
    }).catch(console.error)
  }
})