pokemon.trade/app/javascript/packs/frontend/components/pages/pokemon/CreatePokemon.ts

import {commitMutation, graphql} from 'react-relay';
import {Router} from 'found';

const mutation = graphql`
  mutation CreatePokemonMutation($nickname: String!, $pokedexNumber: ID!) {
    createPokemon(nickname: $nickname, pokedexNumber: $pokedexNumber) {
      pokemon {
        id
        iid
        nickname
        pokedexNumber
      }
    }
  }
`;

/* eslint-disable no-console */
export function createPokemon(
  environment: any,
  router: Router,
  nickname: string,
  pokedexNumber: number
): void {
  const variables = {
    nickname,
    pokedexNumber,
  };

  commitMutation(environment, {
    mutation,
    variables,
    onCompleted: (response, errors): void => {
      console.log('Response received from server: ', response);
      console.log('Errors received from server: ', errors);
      router.push('/pokemon');
    },
    onError: (err): void => console.error(err),
  });
}