Initial commit

frontend/webapp/node_modules/next/dist/server/app-render/collect-segment-data.js

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+"use strict";
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+Object.defineProperty(exports, "collectSegmentData", {
+    enumerable: true,
+    get: function() {
+        return collectSegmentData;
+    }
+});
+const _jsxruntime = require("react/jsx-runtime");
+const _clientedge = require("react-server-dom-webpack/client.edge");
+const _staticedge = require("react-server-dom-webpack/static.edge");
+const _nodewebstreamshelper = require("../stream-utils/node-web-streams-helper");
+const _scheduler = require("../../lib/scheduler");
+const _segmentvalueencoding = require("../../shared/lib/segment-cache/segment-value-encoding");
+const _createerrorhandler = require("./create-error-handler");
+function onSegmentPrerenderError(error) {
+    const digest = (0, _createerrorhandler.getDigestForWellKnownError)(error);
+    if (digest) {
+        return digest;
+    }
+// We don't need to log the errors because we would have already done that
+// when generating the original Flight stream for the whole page.
+}
+async function collectSegmentData(shouldAssumePartialData, fullPageDataBuffer, staleTime, clientModules, serverConsumerManifest, fallbackRouteParams) {
+    // Traverse the router tree and generate a prefetch response for each segment.
+    // A mutable map to collect the results as we traverse the route tree.
+    const resultMap = new Map();
+    // Before we start, warm up the module cache by decoding the page data once.
+    // Then we can assume that any remaining async tasks that occur the next time
+    // are due to hanging promises caused by dynamic data access. Note we only
+    // have to do this once per page, not per individual segment.
+    //
+    try {
+        await (0, _clientedge.createFromReadableStream)((0, _nodewebstreamshelper.streamFromBuffer)(fullPageDataBuffer), {
+            serverConsumerManifest
+        });
+        await (0, _scheduler.waitAtLeastOneReactRenderTask)();
+    } catch  {}
+    // Create an abort controller that we'll use to stop the stream.
+    const abortController = new AbortController();
+    const onCompletedProcessingRouteTree = async ()=>{
+        // Since all we're doing is decoding and re-encoding a cached prerender, if
+        // serializing the stream takes longer than a microtask, it must because of
+        // hanging promises caused by dynamic data.
+        await (0, _scheduler.waitAtLeastOneReactRenderTask)();
+        abortController.abort();
+    };
+    // Generate a stream for the route tree prefetch. While we're walking the
+    // tree, we'll also spawn additional tasks to generate the segment prefetches.
+    // The promises for these tasks are pushed to a mutable array that we will
+    // await once the route tree is fully rendered.
+    const segmentTasks = [];
+    const { prelude: treeStream } = await (0, _staticedge.unstable_prerender)(// RootTreePrefetch is not a valid return type for a React component, but
+    // we need to use a component so that when we decode the original stream
+    // inside of it, the side effects are transferred to the new stream.
+    // @ts-expect-error
+    /*#__PURE__*/ (0, _jsxruntime.jsx)(PrefetchTreeData, {
+        shouldAssumePartialData: shouldAssumePartialData,
+        fullPageDataBuffer: fullPageDataBuffer,
+        fallbackRouteParams: fallbackRouteParams,
+        serverConsumerManifest: serverConsumerManifest,
+        clientModules: clientModules,
+        staleTime: staleTime,
+        segmentTasks: segmentTasks,
+        onCompletedProcessingRouteTree: onCompletedProcessingRouteTree
+    }), clientModules, {
+        signal: abortController.signal,
+        onError: onSegmentPrerenderError
+    });
+    // Write the route tree to a special `/_tree` segment.
+    const treeBuffer = await (0, _nodewebstreamshelper.streamToBuffer)(treeStream);
+    resultMap.set('/_tree', treeBuffer);
+    // Now that we've finished rendering the route tree, all the segment tasks
+    // should have been spawned. Await them in parallel and write the segment
+    // prefetches to the result map.
+    for (const [segmentPath, buffer] of (await Promise.all(segmentTasks))){
+        resultMap.set(segmentPath, buffer);
+    }
+    return resultMap;
+}
+async function PrefetchTreeData({ shouldAssumePartialData, fullPageDataBuffer, fallbackRouteParams, serverConsumerManifest, clientModules, staleTime, segmentTasks, onCompletedProcessingRouteTree }) {
+    // We're currently rendering a Flight response for the route tree prefetch.
+    // Inside this component, decode the Flight stream for the whole page. This is
+    // a hack to transfer the side effects from the original Flight stream (e.g.
+    // Float preloads) onto the Flight stream for the tree prefetch.
+    // TODO: React needs a better way to do this. Needed for Server Actions, too.
+    const initialRSCPayload = await (0, _clientedge.createFromReadableStream)(createUnclosingPrefetchStream((0, _nodewebstreamshelper.streamFromBuffer)(fullPageDataBuffer)), {
+        serverConsumerManifest
+    });
+    const buildId = initialRSCPayload.b;
+    // FlightDataPath is an unsound type, hence the additional checks.
+    const flightDataPaths = initialRSCPayload.f;
+    if (flightDataPaths.length !== 1 && flightDataPaths[0].length !== 3) {
+        console.error('Internal Next.js error: InitialRSCPayload does not match the expected ' + 'shape for a prerendered page during segment prefetch generation.');
+        return null;
+    }
+    const flightRouterState = flightDataPaths[0][0];
+    const seedData = flightDataPaths[0][1];
+    const head = flightDataPaths[0][2];
+    // Compute the route metadata tree by traversing the FlightRouterState. As we
+    // walk the tree, we will also spawn a task to produce a prefetch response for
+    // each segment.
+    const tree = collectSegmentDataImpl(shouldAssumePartialData, flightRouterState, buildId, seedData, fallbackRouteParams, fullPageDataBuffer, clientModules, serverConsumerManifest, _segmentvalueencoding.ROOT_SEGMENT_KEY, segmentTasks);
+    const isHeadPartial = shouldAssumePartialData || await isPartialRSCData(head, clientModules);
+    // Notify the abort controller that we're done processing the route tree.
+    // Anything async that happens after this point must be due to hanging
+    // promises in the original stream.
+    onCompletedProcessingRouteTree();
+    // Render the route tree to a special `/_tree` segment.
+    const treePrefetch = {
+        buildId,
+        tree,
+        head,
+        isHeadPartial,
+        staleTime
+    };
+    return treePrefetch;
+}
+function collectSegmentDataImpl(shouldAssumePartialData, route, buildId, seedData, fallbackRouteParams, fullPageDataBuffer, clientModules, serverConsumerManifest, key, segmentTasks) {
+    // Metadata about the segment. Sent as part of the tree prefetch. Null if
+    // there are no children.
+    let slotMetadata = null;
+    const children = route[1];
+    const seedDataChildren = seedData !== null ? seedData[2] : null;
+    for(const parallelRouteKey in children){
+        const childRoute = children[parallelRouteKey];
+        const childSegment = childRoute[0];
+        const childSeedData = seedDataChildren !== null ? seedDataChildren[parallelRouteKey] : null;
+        const childKey = (0, _segmentvalueencoding.encodeChildSegmentKey)(key, parallelRouteKey, Array.isArray(childSegment) && fallbackRouteParams !== null ? encodeSegmentWithPossibleFallbackParam(childSegment, fallbackRouteParams) : (0, _segmentvalueencoding.encodeSegment)(childSegment));
+        const childTree = collectSegmentDataImpl(shouldAssumePartialData, childRoute, buildId, childSeedData, fallbackRouteParams, fullPageDataBuffer, clientModules, serverConsumerManifest, childKey, segmentTasks);
+        if (slotMetadata === null) {
+            slotMetadata = {};
+        }
+        slotMetadata[parallelRouteKey] = childTree;
+    }
+    if (seedData !== null) {
+        // Spawn a task to write the segment data to a new Flight stream.
+        segmentTasks.push(// Since we're already in the middle of a render, wait until after the
+        // current task to escape the current rendering context.
+        (0, _scheduler.waitAtLeastOneReactRenderTask)().then(()=>renderSegmentPrefetch(shouldAssumePartialData, buildId, seedData, key, clientModules)));
+    } else {
+    // This segment does not have any seed data. Skip generating a prefetch
+    // response for it. We'll still include it in the route tree, though.
+    // TODO: We should encode in the route tree whether a segment is missing
+    // so we don't attempt to fetch it for no reason. As of now this shouldn't
+    // ever happen in practice, though.
+    }
+    // Metadata about the segment. Sent to the client as part of the
+    // tree prefetch.
+    return {
+        segment: route[0],
+        slots: slotMetadata,
+        isRootLayout: route[4] === true
+    };
+}
+function encodeSegmentWithPossibleFallbackParam(segment, fallbackRouteParams) {
+    const name = segment[0];
+    if (!fallbackRouteParams.has(name)) {
+        // Normal case. No matching fallback parameter.
+        return (0, _segmentvalueencoding.encodeSegment)(segment);
+    }
+    // This segment includes a fallback parameter. During prerendering, a random
+    // placeholder value was used; however, for segment prefetches, we need the
+    // segment path to be predictable so the server can create a rewrite for it.
+    // So, replace the placeholder segment value with a "template" string,
+    // e.g. `[name]`.
+    // TODO: This will become a bit cleaner once remove route parameters from the
+    // server response, and instead add them to the segment keys on the client.
+    // Instead of a string replacement, like we do here, route params will always
+    // be encoded in separate step from the rest of the segment, not just in the
+    // case of fallback params.
+    const encodedSegment = (0, _segmentvalueencoding.encodeSegment)(segment);
+    const lastIndex = encodedSegment.lastIndexOf('$');
+    const encodedFallbackSegment = // NOTE: This is guaranteed not to clash with the rest of the segment
+    // because non-simple characters (including [ and ]) trigger a base
+    // 64 encoding.
+    encodedSegment.substring(0, lastIndex + 1) + `[${name}]`;
+    return encodedFallbackSegment;
+}
+async function renderSegmentPrefetch(shouldAssumePartialData, buildId, seedData, key, clientModules) {
+    // Render the segment data to a stream.
+    // In the future, this is where we can include additional metadata, like the
+    // stale time and cache tags.
+    const rsc = seedData[1];
+    const loading = seedData[3];
+    const segmentPrefetch = {
+        buildId,
+        rsc,
+        loading,
+        isPartial: shouldAssumePartialData || await isPartialRSCData(rsc, clientModules)
+    };
+    // Since all we're doing is decoding and re-encoding a cached prerender, if
+    // it takes longer than a microtask, it must because of hanging promises
+    // caused by dynamic data. Abort the stream at the end of the current task.
+    const abortController = new AbortController();
+    (0, _scheduler.waitAtLeastOneReactRenderTask)().then(()=>abortController.abort());
+    const { prelude: segmentStream } = await (0, _staticedge.unstable_prerender)(segmentPrefetch, clientModules, {
+        signal: abortController.signal,
+        onError: onSegmentPrerenderError
+    });
+    const segmentBuffer = await (0, _nodewebstreamshelper.streamToBuffer)(segmentStream);
+    if (key === _segmentvalueencoding.ROOT_SEGMENT_KEY) {
+        return [
+            '/_index',
+            segmentBuffer
+        ];
+    } else {
+        return [
+            key,
+            segmentBuffer
+        ];
+    }
+}
+async function isPartialRSCData(rsc, clientModules) {
+    // We can determine if a segment contains only partial data if it takes longer
+    // than a task to encode, because dynamic data is encoded as an infinite
+    // promise. We must do this in a separate Flight prerender from the one that
+    // actually generates the prefetch stream because we need to include
+    // `isPartial` in the stream itself.
+    let isPartial = false;
+    const abortController = new AbortController();
+    (0, _scheduler.waitAtLeastOneReactRenderTask)().then(()=>{
+        // If we haven't yet finished the outer task, then it must be because we
+        // accessed dynamic data.
+        isPartial = true;
+        abortController.abort();
+    });
+    await (0, _staticedge.unstable_prerender)(rsc, clientModules, {
+        signal: abortController.signal,
+        onError () {}
+    });
+    return isPartial;
+}
+function createUnclosingPrefetchStream(originalFlightStream) {
+    // When PPR is enabled, prefetch streams may contain references that never
+    // resolve, because that's how we encode dynamic data access. In the decoded
+    // object returned by the Flight client, these are reified into hanging
+    // promises that suspend during render, which is effectively what we want.
+    // The UI resolves when it switches to the dynamic data stream
+    // (via useDeferredValue(dynamic, static)).
+    //
+    // However, the Flight implementation currently errors if the server closes
+    // the response before all the references are resolved. As a cheat to work
+    // around this, we wrap the original stream in a new stream that never closes,
+    // and therefore doesn't error.
+    const reader = originalFlightStream.getReader();
+    return new ReadableStream({
+        async pull (controller) {
+            while(true){
+                const { done, value } = await reader.read();
+                if (!done) {
+                    // Pass to the target stream and keep consuming the Flight response
+                    // from the server.
+                    controller.enqueue(value);
+                    continue;
+                }
+                // The server stream has closed. Exit, but intentionally do not close
+                // the target stream.
+                return;
+            }
+        }
+    });
+}
+
+//# sourceMappingURL=collect-segment-data.js.map