GraphQLのクライアントライブラリを使うのはキャッシュのため

GraphQLを使うメリット

スキーマとデータの一致

要求したデータをクライアントが望んだ形で受け取れる

リクエストは1回でいい

GraphQLのクライアントを使う理由はキャッシュをうまく処理してくれるから

GraphQLではHTTPのキャッシュの仕組みは使えない

Modern client applications use caching extensively to improve performance and user experience. And generic HTTP caching just doesn’t work with GraphQL. Every time you request even slightly different data, your HTTP-cached value is invalidated, making it useless for an application of any complexity.

GraphQL data is inherently, well, graphical. And to support GraphQL data effectively, a cache needs to reflect that graphical structure. HTTP caching can’t do this, but a library like Apollo Client can. In our opinion, this is the most important functionality that a GraphQL client library can provide.

https://www.apollographql.com/blog/announcing-the-release-of-apollo-client-3-0/

Apollo Client 3.0

Apollo clientでは正規化されたデータ構造をキャッシュする

クエリが違っても、すでにあるデータをキャッシュから読み取れる

It’s because of the cache-focused philosophy behind Apollo Client that we don’t think of it primarily as a library for executing GraphQL operations, but rather as a library for interacting with a client-side data graph