text: function userSyncRule(user, context, callback) {
    const userId = user.user_id;
    const nickname = user.nickname;
  
    const mutation = `mutation($userId: String!, $nickname: String) {
      insert_users(objects: [{
          id: $userId,
          name: $nickname
        }],
        on_conflict: {
          constraint: users_pkey,
          update_columns: [name]
        }) {
          affected_rows
        }
      }`;
  
    request.post(
      {
        headers: {
          "content-type": "application/json",
          "x-hasura-admin-secret": configuration.ADMIN_SECRET
        },
        url: "https://<your-app-domain>/v1/graphql",
        body: JSON.stringify({ query: mutation, variables: { userId, nickname } })
      },
      function(error, response, body) {
        console.log(body);
        callback(error, user, context);
      }
    );
  }