Client-side schema

You can optionally provide a client-side schema to Apollo Client that defines

As with any GraphQL schema, your client-side schema must be written in

The client-side schema is not used to validate operations like it is on the server (the graphql-js modules for schema validation would dramatically increase your bundle size). Instead, your client-side schema is used for introspection in the

Setup

The following demonstrates how to define a client-side schema and provide it to the ApolloClient constructor:

1
import { ApolloClient, InMemoryCache, gql } from '@apollo/client';
2

3
const typeDefs = gql`
4
  extend type Query {
5
    isLoggedIn: Boolean!
6
    cartItems: [Launch]!
7
  }
8

9
  extend type Launch {
10
    isInCart: Boolean!
11
  }
12

13
  extend type Mutation {
14
    addOrRemoveFromCart(id: ID!): [Launch]
15
  }
16
`;
17

18
const client = new ApolloClient({
19
  cache: new InMemoryCache(),
20
  uri: 'http://localhost:4000/graphql',
21
  typeDefs,
22
});

If you open up the