Clean-up router implementation (#8617)

* Update regarding review comments from #8571

* Update regarding review comments from #8571 (2)

* Update regarding review comments from #8571 (3)

* Update regarding review comments from #8571 (4)
This commit is contained in:
Martin Trapp 2023-09-21 16:21:29 +02:00 committed by GitHub
parent a576ba9c37
commit e8c997db99
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2 changed files with 150 additions and 105 deletions

View file

@ -17,18 +17,26 @@ const { fallback = 'animate' } = Astro.props as Props;
index: number;
scrollX: number;
scrollY: number;
intraPage?: boolean;
};
type Events = 'astro:page-load' | 'astro:after-swap';
// only update history entries that are managed by us
// leave other entries alone and do not accidently add state.
const persistState = (state: State) => history.state && history.replaceState(state, '');
// @ts-expect-error: startViewTransition might exist
const supportsViewTransitions = !!document.startViewTransition;
const transitionEnabledOnThisPage = () =>
!!document.querySelector('[name="astro-view-transitions-enabled"]');
const triggerEvent = (name: Events) => document.dispatchEvent(new Event(name));
const onPageLoad = () => triggerEvent('astro:page-load');
const PERSIST_ATTR = 'data-astro-transition-persist';
const parser = new DOMParser();
// explained at its usage
let noopEl: HTMLDivElement;
if (import.meta.env.DEV) {
noopEl = document.createElement('div');
}
// The History API does not tell you if navigation is forward or back, so
// you can figure it using an index. On pushState the index is incremented so you
@ -40,7 +48,7 @@ const { fallback = 'animate' } = Astro.props as Props;
currentHistoryIndex = history.state.index;
scrollTo({ left: history.state.scrollX, top: history.state.scrollY });
} else if (transitionEnabledOnThisPage()) {
history.replaceState({ index: currentHistoryIndex, scrollX, scrollY }, '');
history.replaceState({ index: currentHistoryIndex, scrollX, scrollY, intraPage: false }, '');
}
const throttle = (cb: (...args: any[]) => any, delay: number) => {
let wait = false;
@ -64,19 +72,28 @@ const { fallback = 'animate' } = Astro.props as Props;
};
};
async function getHTML(href: string) {
// returns the contents of the page or null if the router can't deal with it.
async function fetchHTML(
href: string
): Promise<null | { html: string; redirected?: string; mediaType: DOMParserSupportedType }> {
try {
const res = await fetch(href);
// drop potential charset (+ other name/value pairs) as parser needs the mediaType
const mediaType = res.headers.get('content-type')?.replace(/;.*$/, '');
// the DOMParser can handle two types of HTML
if (mediaType !== 'text/html' && mediaType !== 'application/xhtml+xml') {
// everything else (e.g. audio/mp3) will be handled by the browser but not by us
return null;
}
const html = await res.text();
return {
ok: res.ok,
html,
redirected: res.redirected ? res.url : undefined,
// drop potential charset (+ other name/value pairs) as parser needs the mediaType
mediaType: res.headers.get('content-type')?.replace(/;.*$/, ''),
mediaType,
};
} catch (err) {
return { ok: false };
// can't fetch, let someone else deal with it.
return null;
}
}
@ -98,19 +115,19 @@ const { fallback = 'animate' } = Astro.props as Props;
let wait = Promise.resolve();
for (const script of Array.from(document.scripts)) {
if (script.dataset.astroExec === '') continue;
const s = document.createElement('script');
s.innerHTML = script.innerHTML;
const newScript = document.createElement('script');
newScript.innerHTML = script.innerHTML;
for (const attr of script.attributes) {
if (attr.name === 'src') {
const p = new Promise((r) => {
s.onload = r;
newScript.onload = r;
});
wait = wait.then(() => p as any);
}
s.setAttribute(attr.name, attr.value);
newScript.setAttribute(attr.name, attr.value);
}
s.dataset.astroExec = '';
script.replaceWith(s);
newScript.dataset.astroExec = '';
script.replaceWith(newScript);
}
return wait;
}
@ -122,16 +139,39 @@ const { fallback = 'animate' } = Astro.props as Props;
return style.animationIterationCount === 'infinite';
}
const parser = new DOMParser();
// A noop element used to prevent styles from being removed
if (import.meta.env.DEV) {
var noopEl = document.createElement('div');
const updateHistoryAndScrollPosition = (toLocation) => {
if (toLocation.href !== location.href) {
history.pushState(
{ index: ++currentHistoryIndex, scrollX: 0, scrollY: 0 },
'',
toLocation.href
);
// now we are on the new page for non-history navigations!
// (with history navigation page change happens before popstate is fired)
}
// freshly loaded pages start from the top
scrollTo({ left: 0, top: 0, behavior: 'instant' });
async function updateDOM(newDocument: Document, loc: URL, state?: State, fallback?: Fallback) {
// Check for a head element that should persist, either because it has the data
// attribute or is a link el.
if (toLocation.hash) {
// because we are already on the target page ...
// ... what comes next is a intra-page navigation
// that won't reload the page but instead scroll to the fragment
location.href = toLocation.href;
}
};
// replace head and body of the windows document with contents from newDocument
// if !popstate, update the history entry and scroll position according to toLocation
// if popState is given, this holds the scroll position for history navigation
// if fallback === "animate" then simulate view transitions
async function updateDOM(
newDocument: Document,
toLocation: URL,
popState?: State,
fallback?: Fallback
) {
// Check for a head element that should persist and returns it,
// either because it has the data attribute or is a link el.
const persistedHeadElement = (el: HTMLElement): Element | null => {
const id = el.getAttribute(PERSIST_ATTR);
const newEl = id && newDocument.head.querySelector(`[${PERSIST_ATTR}="${id}"]`);
@ -142,7 +182,11 @@ const { fallback = 'animate' } = Astro.props as Props;
const href = el.getAttribute('href');
return newDocument.head.querySelector(`link[rel=stylesheet][href="${href}"]`);
}
// Only run this in dev. This will get stripped from production builds and is not needed.
// What follows is a fix for an issue (#8472) with missing client:only styles after transition.
// That problem exists only in dev mode where styles are injected into the page by Vite.
// Returning a noop element ensures that the styles are not removed from the old document.
// Guarding the code below with the dev mode check
// allows tree shaking to remove this code in production.
if (import.meta.env.DEV) {
if (el.tagName === 'STYLE' && el.dataset.viteDevId) {
const devId = el.dataset.viteDevId;
@ -158,10 +202,6 @@ const { fallback = 'animate' } = Astro.props as Props;
};
const swap = () => {
// noscript tags inside head element are not honored on swap (#7969).
// Remove them before swapping.
newDocument.querySelectorAll('head noscript').forEach((el) => el.remove());
// swap attributes of the html element
// - delete all attributes from the current document
// - insert all attributes from doc
@ -208,6 +248,8 @@ const { fallback = 'animate' } = Astro.props as Props;
// Persist elements in the existing body
const oldBody = document.body;
// this will reset scroll Position
document.body.replaceWith(newDocument.body);
for (const el of oldBody.querySelectorAll(`[${PERSIST_ATTR}]`)) {
const id = el.getAttribute(PERSIST_ATTR);
@ -219,33 +261,12 @@ const { fallback = 'animate' } = Astro.props as Props;
}
}
// Simulate scroll behavior of Safari and
// Chromium based browsers (Chrome, Edge, Opera, ...)
scrollTo({ left: 0, top: 0, behavior: 'instant' });
if (popState) {
scrollTo(popState.scrollX, popState.scrollY); // usings 'auto' scrollBehavior
} else {
updateHistoryAndScrollPosition(toLocation);
}
let initialScrollX = 0;
let initialScrollY = 0;
if (!state && loc.hash) {
const id = decodeURIComponent(loc.hash.slice(1));
const elem = document.getElementById(id);
// prefer scrollIntoView() over scrollTo() because it takes scroll-padding into account
if (elem) {
elem.scrollIntoView();
initialScrollX = Math.max(
0,
elem.offsetLeft + elem.offsetWidth - document.documentElement.clientWidth
);
initialScrollY = elem.offsetTop;
}
} else if (state) {
scrollTo(state.scrollX, state.scrollY); // usings default scrollBehavior
}
!state &&
history.pushState(
{ index: ++currentHistoryIndex, scrollX: initialScrollX, scrollY: initialScrollY },
'',
loc.href
);
triggerEvent('astro:after-swap');
};
@ -291,32 +312,44 @@ const { fallback = 'animate' } = Astro.props as Props;
}
}
async function navigate(dir: Direction, loc: URL, state?: State) {
async function transition(direction: Direction, toLocation: URL, popState?: State) {
let finished: Promise<void>;
const href = loc.href;
const { html, ok, mediaType, redirected } = await getHTML(href);
// if there was a redirection, show the final URL in the browser's address bar
redirected && (loc = new URL(redirected));
const href = toLocation.href;
const response = await fetchHTML(href);
// If there is a problem fetching the new page, just do an MPA navigation to it.
if (!ok || !(mediaType === 'text/html' || mediaType === 'application/xhtml+xml')) {
if (response === null) {
location.href = href;
return;
}
// if there was a redirection, show the final URL in the browser's address bar
if (response.redirected) {
toLocation = new URL(response.redirected);
}
const newDocument = parser.parseFromString(response.html, response.mediaType);
// The next line might look like a hack,
// but it is actually necessary as noscript elements
// and their contents are returned as markup by the parser,
// see https://developer.mozilla.org/en-US/docs/Web/API/DOMParser/parseFromString
newDocument.querySelectorAll('noscript').forEach((el) => el.remove());
const newDocument = parser.parseFromString(html, mediaType);
if (!newDocument.querySelector('[name="astro-view-transitions-enabled"]')) {
location.href = href;
return;
}
// Now we are sure that we will push state, and it is time to create a state if it is still missing.
!state && history.replaceState({ index: currentHistoryIndex, scrollX, scrollY }, '');
document.documentElement.dataset.astroTransition = dir;
if (!popState) {
// save the current scroll position before we change the DOM and transition to the new page
history.replaceState({ ...history.state, scrollX, scrollY }, '');
}
document.documentElement.dataset.astroTransition = direction;
if (supportsViewTransitions) {
finished = document.startViewTransition(() => updateDOM(newDocument, loc, state)).finished;
// @ts-expect-error: startViewTransition exist
finished = document.startViewTransition(() =>
updateDOM(newDocument, toLocation, popState)
).finished;
} else {
finished = updateDOM(newDocument, loc, state, getFallback());
finished = updateDOM(newDocument, toLocation, popState, getFallback());
}
try {
await finished;
@ -332,7 +365,9 @@ const { fallback = 'animate' } = Astro.props as Props;
// Prefetching
function maybePrefetch(pathname: string) {
if (document.querySelector(`link[rel=prefetch][href="${pathname}"]`)) return;
// @ts-expect-error: connection might exist
if (navigator.connection) {
// @ts-expect-error: connection does exist
let conn = navigator.connection;
if (conn.saveData || /(2|3)g/.test(conn.effectiveType || '')) return;
}
@ -343,8 +378,6 @@ const { fallback = 'animate' } = Astro.props as Props;
}
if (supportsViewTransitions || getFallback() !== 'none') {
markScriptsExec();
document.addEventListener('click', (ev) => {
let link = ev.target;
if (link instanceof Element && link.tagName !== 'A') {
@ -366,51 +399,59 @@ const { fallback = 'animate' } = Astro.props as Props;
ev.ctrlKey || // new tab (windows)
ev.altKey || // download
ev.shiftKey || // new window
ev.defaultPrevented ||
!transitionEnabledOnThisPage()
ev.defaultPrevented
) {
// No page transitions in these cases,
// Let the browser standard action handle this
return;
}
// We do not need to handle same page links because there are no page transitions
// Same page means same path and same query params (but different hash)
if (location.pathname === link.pathname && location.search === link.search) {
if (link.hash) {
// The browser default action will handle navigations with hash fragments
return;
} else {
// Special case: self link without hash
// If handed to the browser it will reload the page
// But we want to handle it like any other same page navigation
// So we scroll to the top of the page but do not start page transitions
ev.preventDefault();
// push state on the first navigation but not if we were here already
if (location.hash) {
history.replaceState(
{ index: currentHistoryIndex, scrollX, scrollY: -(scrollY + 1) },
''
);
const newState: State = { index: ++currentHistoryIndex, scrollX: 0, scrollY: 0 };
history.pushState(newState, '', link.href);
}
scrollTo({ left: 0, top: 0, behavior: 'instant' });
return;
}
}
// these are the cases we will handle: same origin, different page
ev.preventDefault();
navigate('forward', new URL(link.href));
navigate(link.href);
});
function navigate(href) {
// not ours
if (!transitionEnabledOnThisPage()) {
location.href = href;
return;
}
const toLocation = new URL(href, location.href);
// We do not have page transitions on navigations to the same page (intra-page navigation)
// but we want to handle prevent reload on navigation to the same page
// Same page means same origin, path and query params (but maybe different hash)
if (
location.origin === toLocation.origin &&
location.pathname === toLocation.pathname &&
location.search === toLocation.search
) {
// mark current position as non transition intra-page scrolling
if (location.href !== toLocation.href) {
history.replaceState({ ...history.state, intraPage: true }, '');
history.pushState(
{ index: ++currentHistoryIndex, scrollX: 0, scrollY: 0 },
'',
toLocation.href
);
}
if (toLocation.hash) {
location.href = toLocation.href;
} else {
scrollTo({ left: 0, top: 0, behavior: 'instant' });
}
} else {
transition('forward', toLocation);
}
}
addEventListener('popstate', (ev) => {
if (!transitionEnabledOnThisPage() && ev.state) {
// The current page doesn't have View Transitions enabled
// but the page we navigate to does (because it set the state).
// Do a full page refresh to reload the client-side router from the new page.
// Scroll restauration will then happen during the reload when the router's code is re-executed
history.scrollRestoration && (history.scrollRestoration = 'manual');
if (history.scrollRestoration) {
history.scrollRestoration = 'manual';
}
location.reload();
return;
}
@ -433,13 +474,14 @@ const { fallback = 'animate' } = Astro.props as Props;
}
const state: State = history.state;
if (state.intraPage) {
// this is non transition intra-page scrolling
scrollTo(state.scrollX, state.scrollY);
} else {
const nextIndex = state.index;
const direction: Direction = nextIndex > currentHistoryIndex ? 'forward' : 'back';
currentHistoryIndex = nextIndex;
if (state.scrollY < 0) {
scrollTo(state.scrollX, -(state.scrollY + 1));
} else {
navigate(direction, new URL(location.href), state);
transition(direction, new URL(location.href), state);
}
});
@ -461,6 +503,7 @@ const { fallback = 'animate' } = Astro.props as Props;
{ passive: true, capture: true }
);
});
addEventListener('load', onPageLoad);
// There's not a good way to record scroll position before a back button.
// So the way we do it is by listening to scrollend if supported, and if not continuously record the scroll position.
@ -470,5 +513,7 @@ const { fallback = 'animate' } = Astro.props as Props;
if ('onscrollend' in window) addEventListener('scrollend', updateState);
else addEventListener('scroll', throttle(updateState, 300));
markScriptsExec();
}
</script>

View file

@ -293,12 +293,12 @@ test.describe('View Transitions', () => {
locator = page.locator('#click-one-again');
await expect(locator).toBeInViewport();
// Scroll up to top fragment
// goto page 1
await page.click('#click-one-again');
locator = page.locator('#one');
await expect(locator).toHaveText('Page 1');
// Back to middle of the page
// Back to middle of the previous page
await page.goBack();
locator = page.locator('#click-one-again');
await expect(locator).toBeInViewport();