-
Notifications
You must be signed in to change notification settings - Fork 47.2k
/
ReactServerStreamConfigBrowser.js
194 lines (168 loc) · 5.98 KB
/
ReactServerStreamConfigBrowser.js
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
/**
* 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
*/
export type Destination = ReadableStreamController;
export type PrecomputedChunk = Uint8Array;
export opaque type Chunk = Uint8Array;
export type BinaryChunk = Uint8Array;
const channel = new MessageChannel();
const taskQueue = [];
channel.port1.onmessage = () => {
const task = taskQueue.shift();
if (task) {
task();
}
};
export function scheduleWork(callback: () => void) {
taskQueue.push(callback);
channel.port2.postMessage(null);
}
function handleErrorInNextTick(error: any) {
setTimeout(() => {
throw error;
});
}
const LocalPromise = Promise;
export const scheduleMicrotask: (callback: () => void) => void =
typeof queueMicrotask === 'function'
? queueMicrotask
: callback => {
LocalPromise.resolve(null).then(callback).catch(handleErrorInNextTick);
};
export function flushBuffered(destination: Destination) {
// WHATWG Streams do not yet have a way to flush the underlying
// transform streams. https://github.com/whatwg/streams/issues/960
}
const VIEW_SIZE = 2048;
let currentView = null;
let writtenBytes = 0;
export function beginWriting(destination: Destination) {
currentView = new Uint8Array(VIEW_SIZE);
writtenBytes = 0;
}
export function writeChunk(
destination: Destination,
chunk: PrecomputedChunk | Chunk | BinaryChunk,
): void {
if (chunk.byteLength === 0) {
return;
}
if (chunk.byteLength > VIEW_SIZE) {
// this chunk may overflow a single view which implies it was not
// one that is cached by the streaming renderer. We will enqueu
// it directly and expect it is not re-used
if (writtenBytes > 0) {
destination.enqueue(
new Uint8Array(
((currentView: any): Uint8Array).buffer,
0,
writtenBytes,
),
);
currentView = new Uint8Array(VIEW_SIZE);
writtenBytes = 0;
}
destination.enqueue(chunk);
return;
}
let bytesToWrite = chunk;
const allowableBytes = ((currentView: any): Uint8Array).length - writtenBytes;
if (allowableBytes < bytesToWrite.byteLength) {
// this chunk would overflow the current view. We enqueue a full view
// and start a new view with the remaining chunk
if (allowableBytes === 0) {
// the current view is already full, send it
destination.enqueue(currentView);
} else {
// fill up the current view and apply the remaining chunk bytes
// to a new view.
((currentView: any): Uint8Array).set(
bytesToWrite.subarray(0, allowableBytes),
writtenBytes,
);
// writtenBytes += allowableBytes; // this can be skipped because we are going to immediately reset the view
destination.enqueue(currentView);
bytesToWrite = bytesToWrite.subarray(allowableBytes);
}
currentView = new Uint8Array(VIEW_SIZE);
writtenBytes = 0;
}
((currentView: any): Uint8Array).set(bytesToWrite, writtenBytes);
writtenBytes += bytesToWrite.byteLength;
}
export function writeChunkAndReturn(
destination: Destination,
chunk: PrecomputedChunk | Chunk | BinaryChunk,
): boolean {
writeChunk(destination, chunk);
// in web streams there is no backpressure so we can alwas write more
return true;
}
export function completeWriting(destination: Destination) {
if (currentView && writtenBytes > 0) {
destination.enqueue(new Uint8Array(currentView.buffer, 0, writtenBytes));
currentView = null;
writtenBytes = 0;
}
}
export function close(destination: Destination) {
destination.close();
}
const textEncoder = new TextEncoder();
export function stringToChunk(content: string): Chunk {
return textEncoder.encode(content);
}
export function stringToPrecomputedChunk(content: string): PrecomputedChunk {
const precomputedChunk = textEncoder.encode(content);
if (__DEV__) {
if (precomputedChunk.byteLength > VIEW_SIZE) {
console.error(
'precomputed chunks must be smaller than the view size configured for this host. This is a bug in React.',
);
}
}
return precomputedChunk;
}
export function typedArrayToBinaryChunk(
content: $ArrayBufferView,
): BinaryChunk {
// Convert any non-Uint8Array array to Uint8Array. We could avoid this for Uint8Arrays.
// If we passed through this straight to enqueue we wouldn't have to convert it but since
// we need to copy the buffer in that case, we need to convert it to copy it.
// When we copy it into another array using set() it needs to be a Uint8Array.
const buffer = new Uint8Array(
content.buffer,
content.byteOffset,
content.byteLength,
);
// We clone large chunks so that we can transfer them when we write them.
// Others get copied into the target buffer.
return content.byteLength > VIEW_SIZE ? buffer.slice() : buffer;
}
export function byteLengthOfChunk(chunk: Chunk | PrecomputedChunk): number {
return chunk.byteLength;
}
export function byteLengthOfBinaryChunk(chunk: BinaryChunk): number {
return chunk.byteLength;
}
export function closeWithError(destination: Destination, error: mixed): void {
// $FlowFixMe[method-unbinding]
if (typeof destination.error === 'function') {
// $FlowFixMe[incompatible-call]: This is an Error object or the destination accepts other types.
destination.error(error);
} else {
// Earlier implementations doesn't support this method. In that environment you're
// supposed to throw from a promise returned but we don't return a promise in our
// approach. We could fork this implementation but this is environment is an edge
// case to begin with. It's even less common to run this in an older environment.
// Even then, this is not where errors are supposed to happen and they get reported
// to a global callback in addition to this anyway. So it's fine just to close this.
destination.close();
}
}
export {createFastHashJS as createFastHash} from 'react-server/src/createFastHashJS';