nasso.dev
my fork of the bluesky client
Fetch enough pages to fill a page's worth of items (#4863)
* Fetch enough pages to fill a page's worth of items
* Add failsafe in case of appview bug
authored by
GitHub
d2e88cc6
70ffd387
+83
-37
+41
-18
src/state/queries/notifications/feed.ts
+41
-18
src/state/queries/notifications/feed.ts
···
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const moderationOpts = useModerationOpts()
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const unreads = useUnreadNotificationsApi()
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const enabled = opts?.enabled !== false
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const lastPageCountRef = useRef(0)
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const gate = useGate()
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// false: force showing all notifications
···
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},
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})
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// The server may end up returning an empty page, a page with too few items,
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// or a page with items that end up getting filtered out. When we fetch pages,
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// we'll keep track of how many items we actually hope to see. If the server
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// doesn't return enough items, we're going to continue asking for more items.
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const lastItemCount = useRef(0)
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const wantedItemCount = useRef(0)
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const autoPaginationAttemptCount = useRef(0)
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useEffect(() => {
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const {isFetching, hasNextPage, data} = query
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if (isFetching || !hasNextPage) {
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return
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const {data, isLoading, isRefetching, isFetchingNextPage, hasNextPage} =
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query
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// Count the items that we already have.
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let itemCount = 0
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for (const page of data?.pages || []) {
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itemCount += page.items.length
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}
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// avoid double-fires of fetchNextPage()
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if (
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lastPageCountRef.current !== 0 &&
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lastPageCountRef.current === data?.pages?.length
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) {
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return
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// If items got truncated, reset the state we're tracking below.
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if (itemCount !== lastItemCount.current) {
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if (itemCount < lastItemCount.current) {
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wantedItemCount.current = itemCount
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}
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lastItemCount.current = itemCount
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}
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// fetch next page if we haven't gotten a full page of content
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let count = 0
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for (const page of data?.pages || []) {
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count += page.items.length
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}
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if (count < PAGE_SIZE && (data?.pages.length || 0) < 6) {
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query.fetchNextPage()
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lastPageCountRef.current = data?.pages?.length || 0
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// Now track how many items we really want, and fetch more if needed.
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if (isLoading || isRefetching) {
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// During the initial fetch, we want to get an entire page's worth of items.
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wantedItemCount.current = PAGE_SIZE
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} else if (isFetchingNextPage) {
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if (itemCount > wantedItemCount.current) {
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// We have more items than wantedItemCount, so wantedItemCount must be out of date.
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// Some other code must have called fetchNextPage(), for example, from onEndReached.
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// Adjust the wantedItemCount to reflect that we want one more full page of items.
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wantedItemCount.current = itemCount + PAGE_SIZE
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}
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} else if (hasNextPage) {
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// At this point we're not fetching anymore, so it's time to make a decision.
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// If we didn't receive enough items from the server, paginate again until we do.
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if (itemCount < wantedItemCount.current) {
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autoPaginationAttemptCount.current++
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if (autoPaginationAttemptCount.current < 50 /* failsafe */) {
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query.fetchNextPage()
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}
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} else {
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autoPaginationAttemptCount.current = 0
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}
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}
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}, [query])
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+42
-19
src/state/queries/post-feed.ts
+42
-19
src/state/queries/post-feed.ts
···
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args: typeof selectArgs
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result: InfiniteData<FeedPage>
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} | null>(null)
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const lastPageCountRef = useRef(0)
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const isDiscover = feedDesc.includes(DISCOVER_FEED_URI)
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// Make sure this doesn't invalidate unless really needed.
···
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),
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})
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// The server may end up returning an empty page, a page with too few items,
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// or a page with items that end up getting filtered out. When we fetch pages,
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// we'll keep track of how many items we actually hope to see. If the server
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// doesn't return enough items, we're going to continue asking for more items.
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const lastItemCount = useRef(0)
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const wantedItemCount = useRef(0)
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const autoPaginationAttemptCount = useRef(0)
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useEffect(() => {
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const {isFetching, hasNextPage, data} = query
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if (isFetching || !hasNextPage) {
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return
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const {data, isLoading, isRefetching, isFetchingNextPage, hasNextPage} =
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query
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// Count the items that we already have.
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let itemCount = 0
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for (const page of data?.pages || []) {
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for (const slice of page.slices) {
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itemCount += slice.items.length
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}
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}
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// avoid double-fires of fetchNextPage()
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if (
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lastPageCountRef.current !== 0 &&
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lastPageCountRef.current === data?.pages?.length
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) {
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return
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// If items got truncated, reset the state we're tracking below.
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if (itemCount !== lastItemCount.current) {
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if (itemCount < lastItemCount.current) {
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wantedItemCount.current = itemCount
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}
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lastItemCount.current = itemCount
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}
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// fetch next page if we haven't gotten a full page of content
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let count = 0
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for (const page of data?.pages || []) {
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for (const slice of page.slices) {
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count += slice.items.length
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// Now track how many items we really want, and fetch more if needed.
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if (isLoading || isRefetching) {
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// During the initial fetch, we want to get an entire page's worth of items.
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wantedItemCount.current = PAGE_SIZE
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} else if (isFetchingNextPage) {
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if (itemCount > wantedItemCount.current) {
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// We have more items than wantedItemCount, so wantedItemCount must be out of date.
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// Some other code must have called fetchNextPage(), for example, from onEndReached.
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// Adjust the wantedItemCount to reflect that we want one more full page of items.
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wantedItemCount.current = itemCount + PAGE_SIZE
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}
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}
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if (count < PAGE_SIZE && (data?.pages.length || 0) < 6) {
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query.fetchNextPage()
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lastPageCountRef.current = data?.pages?.length || 0
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} else if (hasNextPage) {
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// At this point we're not fetching anymore, so it's time to make a decision.
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// If we didn't receive enough items from the server, paginate again until we do.
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if (itemCount < wantedItemCount.current) {
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autoPaginationAttemptCount.current++
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if (autoPaginationAttemptCount.current < 50 /* failsafe */) {
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query.fetchNextPage()
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}
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} else {
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autoPaginationAttemptCount.current = 0
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}
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}
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}, [query])
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