Files
react/packages/react-server-dom-webpack/src/client/ReactFlightDOMClientEdge.js
T
Hendrik LiebauandGitHub 17bb2f70a0 [Flight] Add unstable_allowPartialStream option to Flight Client (#35731)
When using a partial prerender stream, i.e. a prerender that is
intentionally aborted before all I/O has resolved, consumers of
`createFromReadableStream` would need to keep the stream unclosed to
prevent React Flight from erroring on unresolved chunks. However, some
browsers (e.g. Chrome, Firefox) keep unclosed ReadableStreams with
pending reads as native GC roots, retaining the entire Flight response.

With this PR we're adding an `unstable_allowPartialStream` option, that
allows consumers to close the stream normally. The Flight Client's
`close()` function then transitions pending chunks to halted instead of
erroring them. Halted chunks keep Suspense fallbacks showing (i.e. they
never resolve), and their `.then()` is a no-op so no new listeners
accumulate. Inner stream chunks (ReadableStream/AsyncIterable) are
closed gracefully, and `getChunk()` returns halted chunks for new IDs
that are accessed after closing the response. Blocked chunks are left
alone because they may be waiting on client-side async operations like
module loading, or on forward references to chunks that appeared later
in the stream, both of which resolve independently of closing.
2026-02-09 19:19:32 +01:00

260 lines
6.8 KiB
JavaScript

/**
* Copyright (c) Meta Platforms, Inc. and affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @flow
*/
import type {Thenable, ReactCustomFormAction} from 'shared/ReactTypes.js';
import type {
DebugChannel,
FindSourceMapURLCallback,
Response as FlightResponse,
} from 'react-client/src/ReactFlightClient';
import type {ReactServerValue} from 'react-client/src/ReactFlightReplyClient';
import type {
ServerConsumerModuleMap,
ModuleLoading,
ServerManifest,
} from 'react-client/src/ReactFlightClientConfig';
type ServerConsumerManifest = {
moduleMap: ServerConsumerModuleMap,
moduleLoading: ModuleLoading,
serverModuleMap: null | ServerManifest,
};
import {
createResponse,
createStreamState,
getRoot,
reportGlobalError,
processBinaryChunk,
close,
} from 'react-client/src/ReactFlightClient';
import {
processReply,
createServerReference as createServerReferenceImpl,
} from 'react-client/src/ReactFlightReplyClient';
export {registerServerReference} from 'react-client/src/ReactFlightReplyClient';
import type {TemporaryReferenceSet} from 'react-client/src/ReactFlightTemporaryReferences';
export {createTemporaryReferenceSet} from 'react-client/src/ReactFlightTemporaryReferences';
export type {TemporaryReferenceSet};
function noServerCall() {
throw new Error(
'Server Functions cannot be called during initial render. ' +
'This would create a fetch waterfall. Try to use a Server Component ' +
'to pass data to Client Components instead.',
);
}
export function createServerReference<A: Iterable<any>, T>(
id: any,
callServer: any,
): (...A) => Promise<T> {
return createServerReferenceImpl(id, noServerCall);
}
type EncodeFormActionCallback = <A>(
id: any,
args: Promise<A>,
) => ReactCustomFormAction;
export type Options = {
serverConsumerManifest: ServerConsumerManifest,
nonce?: string,
encodeFormAction?: EncodeFormActionCallback,
temporaryReferences?: TemporaryReferenceSet,
unstable_allowPartialStream?: boolean,
findSourceMapURL?: FindSourceMapURLCallback,
replayConsoleLogs?: boolean,
environmentName?: string,
startTime?: number,
endTime?: number,
// For the Edge client we only support a single-direction debug channel.
debugChannel?: {readable?: ReadableStream, ...},
};
function createResponseFromOptions(options: Options) {
const debugChannel: void | DebugChannel =
__DEV__ && options && options.debugChannel !== undefined
? {
hasReadable: options.debugChannel.readable !== undefined,
callback: null,
}
: undefined;
return createResponse(
options.serverConsumerManifest.moduleMap,
options.serverConsumerManifest.serverModuleMap,
options.serverConsumerManifest.moduleLoading,
noServerCall,
options.encodeFormAction,
typeof options.nonce === 'string' ? options.nonce : undefined,
options && options.temporaryReferences
? options.temporaryReferences
: undefined,
options && options.unstable_allowPartialStream
? options.unstable_allowPartialStream
: false,
__DEV__ && options && options.findSourceMapURL
? options.findSourceMapURL
: undefined,
__DEV__ && options ? options.replayConsoleLogs === true : false, // defaults to false
__DEV__ && options && options.environmentName
? options.environmentName
: undefined,
__DEV__ && options && options.startTime != null
? options.startTime
: undefined,
__DEV__ && options && options.endTime != null ? options.endTime : undefined,
debugChannel,
);
}
function startReadingFromStream(
response: FlightResponse,
stream: ReadableStream,
onDone: () => void,
debugValue: mixed,
): void {
const streamState = createStreamState(response, debugValue);
const reader = stream.getReader();
function progress({
done,
value,
}: {
done: boolean,
value: ?any,
...
}): void | Promise<void> {
if (done) {
return onDone();
}
const buffer: Uint8Array = (value: any);
processBinaryChunk(response, streamState, buffer);
return reader.read().then(progress).catch(error);
}
function error(e: any) {
reportGlobalError(response, e);
}
reader.read().then(progress).catch(error);
}
function createFromReadableStream<T>(
stream: ReadableStream,
options: Options,
): Thenable<T> {
const response: FlightResponse = createResponseFromOptions(options);
if (
__DEV__ &&
options &&
options.debugChannel &&
options.debugChannel.readable
) {
let streamDoneCount = 0;
const handleDone = () => {
if (++streamDoneCount === 2) {
close(response);
}
};
startReadingFromStream(response, options.debugChannel.readable, handleDone);
startReadingFromStream(response, stream, handleDone, stream);
} else {
startReadingFromStream(
response,
stream,
close.bind(null, response),
stream,
);
}
return getRoot(response);
}
function createFromFetch<T>(
promiseForResponse: Promise<Response>,
options: Options,
): Thenable<T> {
const response: FlightResponse = createResponseFromOptions(options);
promiseForResponse.then(
function (r) {
if (
__DEV__ &&
options &&
options.debugChannel &&
options.debugChannel.readable
) {
let streamDoneCount = 0;
const handleDone = () => {
if (++streamDoneCount === 2) {
close(response);
}
};
startReadingFromStream(
response,
options.debugChannel.readable,
handleDone,
);
startReadingFromStream(response, (r.body: any), handleDone, r);
} else {
startReadingFromStream(
response,
(r.body: any),
close.bind(null, response),
r,
);
}
},
function (e) {
reportGlobalError(response, e);
},
);
return getRoot(response);
}
function encodeReply(
value: ReactServerValue,
options?: {temporaryReferences?: TemporaryReferenceSet, signal?: AbortSignal},
): Promise<
string | URLSearchParams | FormData,
> /* We don't use URLSearchParams yet but maybe */ {
return new Promise((resolve, reject) => {
const abort = processReply(
value,
'',
options && options.temporaryReferences
? options.temporaryReferences
: undefined,
resolve,
reject,
);
if (options && options.signal) {
const signal = options.signal;
if (signal.aborted) {
abort((signal: any).reason);
} else {
const listener = () => {
abort((signal: any).reason);
signal.removeEventListener('abort', listener);
};
signal.addEventListener('abort', listener);
}
}
});
}
export {createFromFetch, createFromReadableStream, encodeReply};