next/dist/esm/server/app-render/stale-time.js

The React Framework

import { INFINITE_CACHE } from '../../lib/constants';
/**
 * An AsyncIterable<number> that yields staleTime values. Each call to
 * `update()` yields the new value. When `close()` is called, the iteration
 * ends.
 *
 * This is included in the RSC payload so Flight serializes each yielded value
 * into the stream immediately. If the prerender is aborted by sync IO, the last
 * yielded value is already in the stream, allowing the prerender to be aborted
 * synchronously.
 */ export class StaleTimeIterable {
    update(value) {
        if (this._done) return;
        this.currentValue = value;
        if (this._resolve) {
            this._resolve({
                value,
                done: false
            });
            this._resolve = null;
        } else {
            this._buffer.push(value);
        }
    }
    close() {
        if (this._done) return;
        this._done = true;
        if (this._resolve) {
            this._resolve({
                value: undefined,
                done: true
            });
            this._resolve = null;
        }
    }
    [Symbol.asyncIterator]() {
        return {
            next: ()=>{
                if (this._buffer.length > 0) {
                    return Promise.resolve({
                        value: this._buffer.shift(),
                        done: false
                    });
                }
                if (this._done) {
                    return Promise.resolve({
                        value: undefined,
                        done: true
                    });
                }
                return new Promise((resolve)=>{
                    this._resolve = resolve;
                });
            }
        };
    }
    constructor(){
        this._resolve = null;
        this._done = false;
        this._buffer = [];
        /** The last value passed to `update()`. */ this.currentValue = 0;
    }
}
export function createSelectStaleTime(experimental) {
    return (stale)=>{
        var _experimental_staleTimes;
        return stale === INFINITE_CACHE && typeof ((_experimental_staleTimes = experimental.staleTimes) == null ? void 0 : _experimental_staleTimes.static) === 'number' ? experimental.staleTimes.static : stale;
    };
}
/**
 * Intercepts writes to the `stale` field on the prerender store and yields
 * each update (after applying selectStaleTime) through the iterable. This
 * ensures the latest stale time is always serialized in the Flight stream,
 * even if the prerender is aborted by sync IO.
 */ export function trackStaleTime(store, iterable, selectStaleTime) {
    let _stale = store.stale;
    iterable.update(selectStaleTime(_stale));
    Object.defineProperty(store, 'stale', {
        get: ()=>_stale,
        set: (value)=>{
            _stale = value;
            iterable.update(selectStaleTime(value));
        },
        configurable: true,
        enumerable: true
    });
}
/**
 * Closes the stale time iterable and waits for React to flush the closing
 * chunk into the Flight stream. This also allows the prerender to complete if
 * no other work is pending.
 *
 * Flight's internal work gets scheduled as a microtask when we close the
 * iterable. We need to ensure Flight's pending queues are emptied before this
 * function returns, because the caller will abort the prerender immediately
 * after. We can't use a macrotask (that would allow dynamic IO to sneak into
 * the response), so we use microtasks instead. The exact number of awaits
 * isn't important as long as we wait enough ticks for Flight to finish writing.
 */ export async function finishStaleTimeTracking(iterable) {
    iterable.close();
    await Promise.resolve();
    await Promise.resolve();
    await Promise.resolve();
}

//# sourceMappingURL=stale-time.js.map