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Version: 6.2

useCache()

function useCache(
endpoint: ReadEndpoint,
...args: Parameters<typeof endpoint> | [null]
): Denormalize<typeof endpoint.schema> | null;

Excellent to use data in the normalized cache without fetching.

  • On Error (404, 500, etc):
    • Returns previously cached if exists
    • null otherwise
  • While loading:
    • Returns previously cached if exists
    • null otherwise

Example

Using a type guard to deal with null

function Post({ id }: { id: number }) {
const post = useCache(PostResource.detail(), { id });
// post as PostResource | null
if (!post) return null;
// post as PostResource (typeguarded)
// ...render stuff here
}

Paginated data

When entities are stored in nested structures, that structure will remain.

export class PaginatedPostResource extends Resource {
readonly id: number | null = null;
readonly title: string = '';
readonly content: string = '';

static urlRoot = 'http://test.com/post/';

static list<T extends typeof Resource>(this: T) {
return super.list().extend({
schema: { results: [this], nextPage: '', lastPage: '' },
});
}
}
function ArticleList({ page }: { page: string }) {
const {
results: posts,
nextPage,
lastPage,
} = useCache(PaginatedPostResource.list(), { page });
// posts as PaginatedPostResource[] | null
if (!posts) return null;
// posts as PaginatedPostResource[] (typeguarded)
// ...render stuff here
}

Useful Endpoints to send

Resource provides these built-in:

  • detail()
  • list()

Feel free to add your own Endpoint as well.