effect

Overview

effect is used to execute a side-effect after a mutation has completed whether successful or not.

Usage

Let's extend bookState to display a notification when AddBook mutation is executed.

library/states/book.state.ts

import { state } from '@apollo-orbit/react';
import { AddBookDocument } from '../../graphql';
import { notification } from '../../ui/notification';

export const bookState = state(descriptor => descriptor
  ...
  .effect(AddBookDocument, info => {
    if (info.data?.addBook) {
      notification.success(`New book '${info.data.addBook.name}' was added successfully.`);
    } else if (info.error) {
      notification.error(`Failed to add book '${info.variables?.book.name}': ${info.error.message}`);
    }
  })
);