如何正确键入阿波罗客户端默认选项?

Question

我正在像这样设置阿波罗客户端。

const defaultOptions = {
watchQuery: {
fetchPolicy: 'cache-and-network',
errorPolicy: 'ignore',
},
query: {
fetchPolicy: 'cache-and-network',
errorPolicy: 'all',
},
mutate: {
errorPolicy: 'all',
},
};
return new ApolloClient({
link: ApolloLink.from([authLink, errorLink, webSocketOrHttpLink]),
defaultOptions, // Typescript don't like this.
queryDeduplication: true,
});

打字稿给出此错误：

Type '{ watchQuery: { fetchPolicy: string; errorPolicy: string; }; query: { fetchPolicy: string; errorPolicy: string; }; mutate: { errorPolicy: string; }; }' is not assignable to type 'DefaultOptions'.ts(2322)
ApolloClient.d.ts(23, 5): The expected type comes from property 'defaultOptions' which is declared here on type 'ApolloClientOptions<NormalizedCacheObject>'

根据文档，这就是应该完成的方式。

如何使用正确的类型构建defaultOptions？

Answer 1

如果你检查库的代码，那么，这里似乎有问题

//defination of default options
export interface DefaultOptions {
watchQuery?: Partial<WatchQueryOptions>;
query?: Partial<QueryOptions>;
mutate?: Partial<MutationOptions>;  
}
//defination of QueryOptions
export interface QueryOptions<TVariables = OperationVariables>
extends QueryBaseOptions<TVariables> {
/**
* Specifies the {@link FetchPolicy} to be used for this query
*/
fetchPolicy?: FetchPolicy;
}
//valid value for FetchPolicy type 
export type FetchPolicy =
| 'cache-first'
| 'network-only'
| 'cache-only'
| 'no-cache'
| 'standby';
export type WatchQueryFetchPolicy = FetchPolicy | 'cache-and-network';

因此，对于查询选项，您应该为FetchPolicy传递任何有效值，'cache-and-network'不是有效值。

在此处查看文档： https://github.com/apollographql/apollo-client/blob/main/src/core/watchQueryOptions.ts

Answer 2

2021

：如果您尝试将cache-and-network用作query.fetchPolicy的默认值：

为什么cache-and-network不允许故意用于query的原因早在 2019 年就在这里解释： https://github.com/apollographql/apollo-client/issues/3130#issuecomment-478409066
基本上，query()的行为/逻辑不支持这种策略。因此，他们在打字级别阻止它。

---

React useQuery() hook

如果你使用的是 react，useQuery()钩子遵循watchQuery的行为而不是query。因此，配置watchQuery就足够了：

import {
ApolloClient,
InMemoryCache,
HttpLink,
DefaultOptions
} from "@apollo/client";
const defaultOptions: DefaultOptions = {
watchQuery: {
fetchPolicy: "cache-and-network",
errorPolicy: "ignore",
notifyOnNetworkStatusChange: true
}
};
export const platformClient = new ApolloClient({
link: new HttpLink({
uri: "https://xxxxx",
credentials: "same-origin"
}),
cache: new InMemoryCache(),
defaultOptions
});