我有来自 NextJS 官方示例 repo 的以下 apolloClient.js 文件:
import { ApolloClient, HttpLink, InMemoryCache } from '@apollo/client'
import { concatPagination } from '@apollo/client/utilities'
import merge from 'deepmerge'
import isEqual from 'lodash/isEqual'
import { useMemo } from 'react'
export const APOLLO_STATE_PROP_NAME = '__APOLLO_STATE__'
let apolloClient
function createApolloClient() {
return new ApolloClient({
ssrMode: typeof window === 'undefined',
link: new HttpLink({
uri: 'https://nextjs-graphql-with-prisma-simple.vercel.app/api', // Server URL (must be absolute)
credentials: 'same-origin', // Additional fetch() options like `credentials` or `headers`
}),
cache: new InMemoryCache({
typePolicies: {
Query: {
fields: {
allPosts: concatPagination(),
},
},
},
}),
})
}
export function initializeApollo(initialState = null) {
const _apolloClient = apolloClient ?? createApolloClient()
// If your page has Next.js data fetching methods that use Apollo Client, the initial state
// gets hydrated here
if (initialState) {
// Get existing cache, loaded during client side data fetching
const existingCache = _apolloClient.extract()
// Merge the existing cache into data passed from getStaticProps/getServerSideProps
const data = merge(initialState, existingCache, {
// combine arrays using object equality (like in sets)
arrayMerge: (destinationArray, sourceArray) => [
...sourceArray,
...destinationArray.filter((d) =>
sourceArray.every((s) => !isEqual(d, s))
),
],
})
// Restore the cache with the merged data
_apolloClient.cache.restore(data)
}
// For SSG and SSR always create a new Apollo Client
if (typeof window === 'undefined') return _apolloClient
// Create the Apollo Client once in the client
if (!apolloClient) apolloClient = _apolloClient
return _apolloClient
}
export function addApolloState(client, pageProps) {
if (pageProps?.props) {
pageProps.props[APOLLO_STATE_PROP_NAME] = client.cache.extract()
}
return pageProps
}
export function useApollo(pageProps) {
const state = pageProps[APOLLO_STATE_PROP_NAME]
const store = useMemo(() => initializeApollo(state), [state])
return store
}
我有两个页面:page1.js 使用 Apollo 钩子 (useQuery()) 和第二个页面 page2.js,它什么都不做,只返回 null。问题是,如果我使用 Chrome 扩展程序检查 Apollo 缓存,则 page1 上的查询的缓存结果不会出现在 page2 上。
如何仅使用 1 个全局缓存并防止在页面转换之间重新初始化缓存?