Sync Users Between Auth0 and Hasura - Auth0 Custom Action

hasura-jwt-sync-auth0-action-post-login.js

/**
* Handler that will be called during the execution of a PostLogin flow.
*
* @param {Event} event - Details about the user and the context in which they are logging in.
* @param {PostLoginAPI} api - Interface whose methods can be used to change the behavior of the login.
*/
exports.onExecutePostLogin = async (event, api) => {
  var request = require('request');
  const userId = event.user.user_id;
  const userName = event.user.username;
  const email = event.user.email;

  const admin_secret = event.secrets.HASURA_ADMIN_SECRET;
  const url = "https://your-domain-here.hasura.app/v1/graphql";
  const query = `mutation($userId: String!, $userName: String, $email: String) {
    insert_users(objects: [{
      id: $userId, name: $userName, email: $email, last_seen: "now()"
    }], on_conflict: {constraint: users_pkey, update_columns: [last_seen, name, email]}
    ) {
      affected_rows
    }
  }`;

  const variables = { userId, userName, email };
  request.post({
      url: url,
      headers: {'content-type' : 'application/json', 'x-hasura-admin-secret': admin_secret},
      body: JSON.stringify({
        query: query,
        variables: variables
      })
  }, function(error, response, body){
       console.log(body);
  });
};


/**
* Handler that will be invoked when this action is resuming after an external redirect. If your
* onExecutePostLogin function does not perform a redirect, this function can be safely ignored.
*
* @param {Event} event - Details about the user and the context in which they are logging in.
* @param {PostLoginAPI} api - Interface whose methods can be used to change the behavior of the login.
*/
// exports.onContinuePostLogin = async (event, api) => {
// };

Create a secret in Auth0 on the left (key icon):
Enter for Key HASURA_ADMIN_SECRET and put your Hasura Admin Secret got from the Hasura console on the value.

Create a dependency:
On the left (package Icon) where it reads name add:
request

Do not forget to replace https://your-domain-here.hasura.app/v1/graphql with your graphql url