Files
react-navigation/packages/native/src/useLinking.tsx
2020-12-03 01:56:28 +01:00

548 lines
18 KiB
TypeScript

import * as React from 'react';
import {
getStateFromPath as getStateFromPathDefault,
getPathFromState as getPathFromStateDefault,
NavigationContainerRef,
NavigationState,
getActionFromState,
} from '@react-navigation/core';
import { nanoid } from 'nanoid/non-secure';
import ServerContext from './ServerContext';
import type { LinkingOptions } from './types';
type ResultState = ReturnType<typeof getStateFromPathDefault>;
type HistoryRecord = {
// Unique identifier for this record to match it with window.history.state
id: string;
// Navigation state object for the history entry
state: NavigationState;
// Path of the history entry
path: string;
};
const createMemoryHistory = () => {
let index = 0;
let items: HistoryRecord[] = [];
// Pending callbacks for `history.go(n)`
// We might modify the callback stored if it was interrupted, so we have a ref to identify it
const pending: { ref: unknown; cb: (interrupted?: boolean) => void }[] = [];
const interrupt = () => {
// If another history operation was performed we need to interrupt existing ones
// This makes sure that calls such as `history.replace` after `history.go` don't happen
// Since otherwise it won't be correct if something else has changed
pending.forEach((it) => {
const cb = it.cb;
it.cb = () => cb(true);
});
};
const history = {
get index(): number {
// We store an id in the state instead of an index
// Index could get out of sync with in-memory values if page reloads
const id = window.history.state?.id;
if (id) {
const index = items.findIndex((item) => item.id === id);
return index > -1 ? index : 0;
}
return 0;
},
get(index: number) {
return items[index];
},
backIndex({ path }: { path: string }) {
// We need to find the index from the element before current to get closest path to go back to
for (let i = index - 1; i >= 0; i--) {
const item = items[i];
if (item.path === path) {
return i;
}
}
return -1;
},
push({ path, state }: { path: string; state: NavigationState }) {
interrupt();
const id = nanoid();
// When a new entry is pushed, all the existing entries after index will be inaccessible
// So we remove any existing entries after the current index to clean them up
items = items.slice(0, index + 1);
items.push({ path, state, id });
index = items.length - 1;
// We pass empty string for title because it's ignored in all browsers except safari
// We don't store state object in history.state because:
// - browsers have limits on how big it can be, and we don't control the size
// - while not recommended, there could be non-serializable data in state
window.history.pushState({ id }, '', path);
},
replace({ path, state }: { path: string; state: NavigationState }) {
interrupt();
const id = window.history.state?.id ?? nanoid();
if (items.length) {
items[index] = { path, state, id };
} else {
// This is the first time any state modifications are done
// So we need to push the entry as there's nothing to replace
items.push({ path, state, id });
}
window.history.replaceState({ id }, '', path);
},
// `history.go(n)` is asynchronous, there are couple of things to keep in mind:
// - it won't do anything if we can't go `n` steps, the `popstate` event won't fire.
// - each `history.go(n)` call will trigger a separate `popstate` event with correct location.
// - the `popstate` event fires before the next frame after calling `history.go(n)`.
// This method differs from `history.go(n)` in the sense that it'll go back as many steps it can.
go(n: number) {
interrupt();
if (n > 0) {
// We shouldn't go forward more than available index
n = Math.min(n, items.length - 1);
} else if (n < 0) {
// We shouldn't go back more than the 0 index
// Otherwise we'll exit the page
n = index + n < 0 ? -index : n;
}
if (n === 0) {
return;
}
index += n;
// When we call `history.go`, `popstate` will fire when there's history to go back to
// So we need to somehow handle following cases:
// - There's history to go back, `history.go` is called, and `popstate` fires
// - `history.go` is called multiple times, we need to resolve on respective `popstate`
// - No history to go back, but `history.go` was called, browser has no API to detect it
return new Promise<void>((resolve, reject) => {
const done = (interrupted?: boolean) => {
clearTimeout(timer);
if (interrupted) {
reject(new Error('History was changed during navigation.'));
return;
}
// There seems to be a bug in Chrome regarding updating the title
// If we set a title just before calling `history.go`, the title gets lost
// However the value of `document.title` is still what we set it to
// It's just not displayed in the tab bar
// To update the tab bar, we need to reset the title to something else first (e.g. '')
// And set the title to what it was before so it gets applied
// It won't work without setting it to empty string coz otherwise title isn't changing
// Which means that the browser won't do anything after setting the title
const { title } = window.document;
window.document.title = '';
window.document.title = title;
resolve();
};
pending.push({ ref: done, cb: done });
// If navigation didn't happen within 100ms, assume that it won't happen
// This may not be accurate, but hopefully it won't take so much time
// In Chrome, navigation seems to happen instantly in next microtask
// But on Firefox, it seems to take much longer, around 50ms from our testing
// We're using a hacky timeout since there doesn't seem to be way to know for sure
const timer = setTimeout(() => {
const index = pending.findIndex((it) => it.ref === done);
if (index > -1) {
pending[index].cb();
pending.splice(index, 1);
}
}, 100);
const onPopState = () => {
const last = pending.pop();
window.removeEventListener('popstate', onPopState);
last?.cb();
};
window.addEventListener('popstate', onPopState);
window.history.go(n);
});
},
// The `popstate` event is triggered when history changes, except `pushState` and `replaceState`
// If we call `history.go(n)` ourselves, we don't want it to trigger the listener
// Here we normalize it so that only external changes (e.g. user pressing back/forward) trigger the listener
listen(listener: () => void) {
const onPopState = () => {
if (pending.length) {
// This was triggered by `history.go(n)`, we shouldn't call the listener
return;
}
listener();
};
window.addEventListener('popstate', onPopState);
return () => window.removeEventListener('popstate', onPopState);
},
};
return history;
};
/**
* Find the matching navigation state that changed between 2 navigation states
* e.g.: a -> b -> c -> d and a -> b -> c -> e -> f, if history in b changed, b is the matching state
*/
const findMatchingState = <T extends NavigationState>(
a: T | undefined,
b: T | undefined
): [T | undefined, T | undefined] => {
if (a === undefined || b === undefined || a.key !== b.key) {
return [undefined, undefined];
}
// Tab and drawer will have `history` property, but stack will have history in `routes`
const aHistoryLength = a.history ? a.history.length : a.routes.length;
const bHistoryLength = b.history ? b.history.length : b.routes.length;
const aRoute = a.routes[a.index];
const bRoute = b.routes[b.index];
const aChildState = aRoute.state as T | undefined;
const bChildState = bRoute.state as T | undefined;
// Stop here if this is the state object that changed:
// - history length is different
// - focused routes are different
// - one of them doesn't have child state
// - child state keys are different
if (
aHistoryLength !== bHistoryLength ||
aRoute.key !== bRoute.key ||
aChildState === undefined ||
bChildState === undefined ||
aChildState.key !== bChildState.key
) {
return [a, b];
}
return findMatchingState(aChildState, bChildState);
};
/**
* Run async function in series as it's called.
*/
const series = (cb: () => Promise<void>) => {
// Whether we're currently handling a callback
let handling = false;
let queue: (() => Promise<void>)[] = [];
const callback = async () => {
try {
if (handling) {
// If we're currently handling a previous event, wait before handling this one
// Add the callback to the beginning of the queue
queue.unshift(callback);
return;
}
handling = true;
await cb();
} finally {
handling = false;
if (queue.length) {
// If we have queued items, handle the last one
const last = queue.pop();
last?.();
}
}
};
return callback;
};
let isUsingLinking = false;
export default function useLinking(
ref: React.RefObject<NavigationContainerRef>,
{
enabled = true,
config,
getStateFromPath = getStateFromPathDefault,
getPathFromState = getPathFromStateDefault,
}: LinkingOptions
) {
React.useEffect(() => {
if (enabled !== false && isUsingLinking) {
throw new Error(
[
'Looks like you have configured linking in multiple places. This is likely an error since URL integration should only be handled in one place to avoid conflicts. Make sure that:',
"- You are not using both 'linking' prop and 'useLinking'",
"- You don't have 'useLinking' in multiple components",
]
.join('\n')
.trim()
);
} else {
isUsingLinking = enabled !== false;
}
return () => {
isUsingLinking = false;
};
});
const [history] = React.useState(createMemoryHistory);
// We store these options in ref to avoid re-creating getInitialState and re-subscribing listeners
// This lets user avoid wrapping the items in `React.useCallback` or `React.useMemo`
// Not re-creating `getInitialState` is important coz it makes it easier for the user to use in an effect
const enabledRef = React.useRef(enabled);
const configRef = React.useRef(config);
const getStateFromPathRef = React.useRef(getStateFromPath);
const getPathFromStateRef = React.useRef(getPathFromState);
React.useEffect(() => {
enabledRef.current = enabled;
configRef.current = config;
getStateFromPathRef.current = getStateFromPath;
getPathFromStateRef.current = getPathFromState;
}, [config, enabled, getPathFromState, getStateFromPath]);
const server = React.useContext(ServerContext);
const getInitialState = React.useCallback(() => {
let value: ResultState | undefined;
if (enabledRef.current) {
const location =
server?.location ??
(typeof window !== 'undefined' ? window.location : undefined);
const path = location ? location.pathname + location.search : undefined;
if (path) {
value = getStateFromPathRef.current(path, configRef.current);
}
}
// Make it a thenable to keep consistent with the native impl
const thenable = {
then(onfulfilled?: (state: ResultState | undefined) => void) {
return Promise.resolve(onfulfilled ? onfulfilled(value) : value);
},
catch() {
return thenable;
},
};
return thenable as PromiseLike<ResultState | undefined>;
// eslint-disable-next-line react-hooks/exhaustive-deps
}, []);
const previousIndexRef = React.useRef<number | undefined>(undefined);
const previousStateRef = React.useRef<NavigationState | undefined>(undefined);
const pendingPopStatePathRef = React.useRef<string | undefined>(undefined);
React.useEffect(() => {
previousIndexRef.current = history.index;
return history.listen(() => {
const navigation = ref.current;
if (!navigation || !enabled) {
return;
}
const path = location.pathname + location.search;
const index = history.index;
const previousIndex = previousIndexRef.current ?? 0;
previousIndexRef.current = index;
pendingPopStatePathRef.current = path;
// When browser back/forward is clicked, we first need to check if state object for this index exists
// If it does we'll reset to that state object
// Otherwise, we'll handle it like a regular deep link
const record = history.get(index);
if (record?.path === path && record?.state) {
navigation.resetRoot(record.state);
return;
}
const state = getStateFromPathRef.current(path, configRef.current);
// We should only dispatch an action when going forward
// Otherwise the action will likely add items to history, which would mess things up
if (state) {
// Make sure that the routes in the state exist in the root navigator
// Otherwise there's an error in the linking configuration
const rootState = navigation.getRootState();
if (state.routes.some((r) => !rootState?.routeNames.includes(r.name))) {
console.warn(
"The navigation state parsed from the URL contains routes not present in the root navigator. This usually means that the linking configuration doesn't match the navigation structure. See https://reactnavigation.org/docs/configuring-links for more details on how to specify a linking configuration."
);
return;
}
if (index > previousIndex) {
const action = getActionFromState(state, configRef.current);
if (action !== undefined) {
try {
navigation.dispatch(action);
} catch (e) {
// Ignore any errors from deep linking.
// This could happen in case of malformed links, navigation object not being initialized etc.
console.warn(
`An error occurred when trying to handle the link '${path}': ${e.message}`
);
}
} else {
navigation.resetRoot(state);
}
} else {
navigation.resetRoot(state);
}
} else {
// if current path didn't return any state, we should revert to initial state
navigation.resetRoot(state);
}
});
}, [enabled, history, ref]);
React.useEffect(() => {
if (!enabled) {
return;
}
if (ref.current) {
// We need to record the current metadata on the first render if they aren't set
// This will allow the initial state to be in the history entry
const state = ref.current.getRootState();
if (state) {
const path = getPathFromStateRef.current(state, configRef.current);
if (previousStateRef.current === undefined) {
previousStateRef.current = state;
}
history.replace({ path, state });
}
}
const onStateChange = async () => {
const navigation = ref.current;
if (!navigation || !enabled) {
return;
}
const previousState = previousStateRef.current;
const state = navigation.getRootState();
const pendingPath = pendingPopStatePathRef.current;
const path = getPathFromStateRef.current(state, configRef.current);
previousStateRef.current = state;
pendingPopStatePathRef.current = undefined;
// To detect the kind of state change, we need to:
// - Find the common focused navigation state in previous and current state
// - If only the route keys changed, compare history/routes.length to check if we go back/forward/replace
// - If no common focused navigation state found, it's a replace
const [previousFocusedState, focusedState] = findMatchingState(
previousState,
state
);
if (
previousFocusedState &&
focusedState &&
// We should only handle push/pop if path changed from what was in last `popstate`
// Otherwise it's likely a change triggered by `popstate`
path !== pendingPath
) {
const historyDelta =
(focusedState.history
? focusedState.history.length
: focusedState.routes.length) -
(previousFocusedState.history
? previousFocusedState.history.length
: previousFocusedState.routes.length);
if (historyDelta > 0) {
// If history length is increased, we should pushState
// Note that path might not actually change here, for example, drawer open should pushState
history.push({ path, state });
} else if (historyDelta < 0) {
// If history length is decreased, i.e. entries were removed, we want to go back
const nextIndex = history.backIndex({ path });
const currentIndex = history.index;
try {
if (nextIndex !== -1 && nextIndex < currentIndex) {
// An existing entry for this path exists and it's less than current index, go back to that
await history.go(nextIndex - currentIndex);
} else {
// We couldn't find an existing entry to go back to, so we'll go back by the delta
// This won't be correct if multiple routes were pushed in one go before
// Usually this shouldn't happen and this is a fallback for that
await history.go(historyDelta);
}
// Store the updated state as well as fix the path if incorrect
history.replace({ path, state });
} catch (e) {
// The navigation was interrupted
}
} else {
// If history length is unchanged, we want to replaceState
history.replace({ path, state });
}
} else {
// If no common navigation state was found, assume it's a replace
// This would happen if the user did a reset/conditionally changed navigators
history.replace({ path, state });
}
};
// We debounce onStateChange coz we don't want multiple state changes to be handled at one time
// This could happen since `history.go(n)` is asynchronous
// If `pushState` or `replaceState` were called before `history.go(n)` completes, it'll mess stuff up
return ref.current?.addListener('state', series(onStateChange));
});
return {
getInitialState,
};
}