API for Dependent Queries #4829
Description
An issue that comes up regularly is building queries that want to pull data from other queries: #4828 #1171 to name a few
These queries would need to:
- be provided the data from the dependent queries
- rerun if any of those dependent queries refetch
- act as a subscription for those queries (so their cache sticks around), unsubscribing when its own cache entry is removed
API still TBC, but some ideas raised in maintainers' chat:
build.query({ query(arg, dependencies) { return `foo/${dependencies.first.id}` }, dependencies(arg){ return { first: { endpoint: "ep1", args: arg.foo } } } })build.withDependencies( (arg)=> { return { first: { endpoint: "ep1", args: arg.foo } } } ).query({ query(arg, dependencies) { return `foo/${dependencies.first.id}` } })build.withDependencies( (arg)=> { return { first: api.endpoints.ep1.createDep(arg.foo) } } ).query({ query(arg, dependencies) { return `foo/${dependencies.first.id}` } })async queryFn(postId, { dependentQuery }) { const comments = await dependentQuery("getComments", postId); const commentMetadata = await Promise.all( comments.map((comment) => dependentQuery("getCommentMetadata", comment.id)), ); return { data: commentMetadata }; }async queryFn(arg, api, extraOptions, fetchWithBq) { const first = await api.dependentQuery("ep1", arg.foo); if (first.error) return first; return fetchWithBq(`foo/${first.data.id}`); }