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denoland-deno/std/node/_stream/readable.ts

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// Copyright Node.js contributors. All rights reserved. MIT License.
import EventEmitter, { captureRejectionSymbol } from "../events.ts";
import Stream from "./stream.ts";
import { Buffer } from "../buffer.ts";
import BufferList from "./buffer_list.ts";
import {
ERR_INVALID_OPT_VALUE,
ERR_METHOD_NOT_IMPLEMENTED,
ERR_MULTIPLE_CALLBACK,
ERR_STREAM_PUSH_AFTER_EOF,
ERR_STREAM_UNSHIFT_AFTER_END_EVENT,
} from "../_errors.ts";
import { StringDecoder } from "../string_decoder.ts";
import createReadableStreamAsyncIterator from "./async_iterator.ts";
import streamFrom from "./from.ts";
import { kConstruct, kDestroy, kPaused } from "./symbols.ts";
import type Writable from "./writable.ts";
import { errorOrDestroy as errorOrDestroyDuplex } from "./duplex.ts";
function construct(stream: Readable, cb: () => void) {
const r = stream._readableState;
if (!stream._construct) {
return;
}
stream.once(kConstruct, cb);
r.constructed = false;
queueMicrotask(() => {
let called = false;
stream._construct?.((err?: Error) => {
r.constructed = true;
if (called) {
err = new ERR_MULTIPLE_CALLBACK();
} else {
called = true;
}
if (r.destroyed) {
stream.emit(kDestroy, err);
} else if (err) {
errorOrDestroy(stream, err, true);
} else {
queueMicrotask(() => stream.emit(kConstruct));
}
});
});
}
function _destroy(
self: Readable,
err?: Error,
cb?: (error?: Error | null) => void,
) {
self._destroy(err || null, (err) => {
const r = (self as Readable)._readableState;
if (err) {
// Avoid V8 leak, https://github.com/nodejs/node/pull/34103#issuecomment-652002364
err.stack;
if (!r.errored) {
r.errored = err;
}
}
r.closed = true;
if (typeof cb === "function") {
cb(err);
}
if (err) {
queueMicrotask(() => {
if (!r.errorEmitted) {
r.errorEmitted = true;
self.emit("error", err);
}
r.closeEmitted = true;
if (r.emitClose) {
self.emit("close");
}
});
} else {
queueMicrotask(() => {
r.closeEmitted = true;
if (r.emitClose) {
self.emit("close");
}
});
}
});
}
function errorOrDestroy(stream: Readable, err: Error, sync = false) {
const r = stream._readableState;
if (r.destroyed) {
return stream;
}
if (r.autoDestroy) {
stream.destroy(err);
} else if (err) {
// Avoid V8 leak, https://github.com/nodejs/node/pull/34103#issuecomment-652002364
err.stack;
if (!r.errored) {
r.errored = err;
}
if (sync) {
queueMicrotask(() => {
if (!r.errorEmitted) {
r.errorEmitted = true;
stream.emit("error", err);
}
});
} else if (!r.errorEmitted) {
r.errorEmitted = true;
stream.emit("error", err);
}
}
}
function flow(stream: Readable) {
const state = stream._readableState;
while (state.flowing && stream.read() !== null);
}
function pipeOnDrain(src: Readable, dest: Writable) {
return function pipeOnDrainFunctionResult() {
const state = src._readableState;
if (state.awaitDrainWriters === dest) {
state.awaitDrainWriters = null;
} else if (state.multiAwaitDrain) {
(state.awaitDrainWriters as Set<Writable>).delete(dest);
}
if (
(!state.awaitDrainWriters ||
(state.awaitDrainWriters as Set<Writable>).size === 0) &&
src.listenerCount("data")
) {
state.flowing = true;
flow(src);
}
};
}
function updateReadableListening(self: Readable) {
const state = self._readableState;
state.readableListening = self.listenerCount("readable") > 0;
if (state.resumeScheduled && state[kPaused] === false) {
// Flowing needs to be set to true now, otherwise
// the upcoming resume will not flow.
state.flowing = true;
// Crude way to check if we should resume.
} else if (self.listenerCount("data") > 0) {
self.resume();
} else if (!state.readableListening) {
state.flowing = null;
}
}
function nReadingNextTick(self: Readable) {
self.read(0);
}
function resume(stream: Readable, state: ReadableState) {
if (!state.resumeScheduled) {
state.resumeScheduled = true;
queueMicrotask(() => resume_(stream, state));
}
}
function resume_(stream: Readable, state: ReadableState) {
if (!state.reading) {
stream.read(0);
}
state.resumeScheduled = false;
stream.emit("resume");
flow(stream);
if (state.flowing && !state.reading) {
stream.read(0);
}
}
function readableAddChunk(
stream: Readable,
chunk: string | Buffer | Uint8Array | null,
encoding: undefined | string = undefined,
addToFront: boolean,
) {
const state = stream._readableState;
let usedEncoding = encoding;
let err;
if (!state.objectMode) {
if (typeof chunk === "string") {
usedEncoding = encoding || state.defaultEncoding;
if (state.encoding !== usedEncoding) {
if (addToFront && state.encoding) {
chunk = Buffer.from(chunk, usedEncoding).toString(state.encoding);
} else {
chunk = Buffer.from(chunk, usedEncoding);
usedEncoding = "";
}
}
} else if (chunk instanceof Uint8Array) {
chunk = Buffer.from(chunk);
}
}
if (err) {
errorOrDestroy(stream, err);
} else if (chunk === null) {
state.reading = false;
onEofChunk(stream, state);
} else if (state.objectMode || (chunk.length > 0)) {
if (addToFront) {
if (state.endEmitted) {
errorOrDestroy(stream, new ERR_STREAM_UNSHIFT_AFTER_END_EVENT());
} else {
addChunk(stream, state, chunk, true);
}
} else if (state.ended) {
errorOrDestroy(stream, new ERR_STREAM_PUSH_AFTER_EOF());
} else if (state.destroyed || state.errored) {
return false;
} else {
state.reading = false;
if (state.decoder && !usedEncoding) {
//TODO(Soremwar)
//I don't think this cast is right
chunk = state.decoder.write(Buffer.from(chunk as Uint8Array));
if (state.objectMode || chunk.length !== 0) {
addChunk(stream, state, chunk, false);
} else {
maybeReadMore(stream, state);
}
} else {
addChunk(stream, state, chunk, false);
}
}
} else if (!addToFront) {
state.reading = false;
maybeReadMore(stream, state);
}
return !state.ended &&
(state.length < state.highWaterMark || state.length === 0);
}
function addChunk(
stream: Readable,
state: ReadableState,
chunk: string | Buffer | Uint8Array,
addToFront: boolean,
) {
if (state.flowing && state.length === 0 && !state.sync) {
if (state.multiAwaitDrain) {
(state.awaitDrainWriters as Set<Writable>).clear();
} else {
state.awaitDrainWriters = null;
}
stream.emit("data", chunk);
} else {
// Update the buffer info.
state.length += state.objectMode ? 1 : chunk.length;
if (addToFront) {
state.buffer.unshift(chunk);
} else {
state.buffer.push(chunk);
}
if (state.needReadable) {
emitReadable(stream);
}
}
maybeReadMore(stream, state);
}
function prependListener(
emitter: EventEmitter,
event: string,
// deno-lint-ignore no-explicit-any
fn: (...args: any[]) => any,
) {
if (typeof emitter.prependListener === "function") {
return emitter.prependListener(event, fn);
}
// This is a hack to make sure that our error handler is attached before any
// userland ones. NEVER DO THIS. This is here only because this code needs
// to continue to work with older versions of Node.js that do not include
//the prependListener() method. The goal is to eventually remove this hack.
// TODO(Soremwar)
// Burn it with fire
// deno-lint-ignore ban-ts-comment
//@ts-ignore
if (emitter._events.get(event)?.length) {
// deno-lint-ignore ban-ts-comment
//@ts-ignore
const listeners = [fn, ...emitter._events.get(event)];
// deno-lint-ignore ban-ts-comment
//@ts-ignore
emitter._events.set(event, listeners);
} else {
emitter.on(event, fn);
}
}
/** Pluck off n bytes from an array of buffers.
* Length is the combined lengths of all the buffers in the list.
* This function is designed to be inlinable, so please take care when making
* changes to the function body.
*/
function fromList(n: number, state: ReadableState) {
// nothing buffered.
if (state.length === 0) {
return null;
}
let ret;
if (state.objectMode) {
ret = state.buffer.shift();
} else if (!n || n >= state.length) {
if (state.decoder) {
ret = state.buffer.join("");
} else if (state.buffer.length === 1) {
ret = state.buffer.first();
} else {
ret = state.buffer.concat(state.length);
}
state.buffer.clear();
} else {
ret = state.buffer.consume(n, !!state.decoder);
}
return ret;
}
function endReadable(stream: Readable) {
const state = stream._readableState;
if (!state.endEmitted) {
state.ended = true;
queueMicrotask(() => endReadableNT(state, stream));
}
}
function endReadableNT(state: ReadableState, stream: Readable) {
if (
!state.errorEmitted && !state.closeEmitted &&
!state.endEmitted && state.length === 0
) {
state.endEmitted = true;
stream.emit("end");
if (state.autoDestroy) {
stream.destroy();
}
}
}
// Don't raise the hwm > 1GB.
const MAX_HWM = 0x40000000;
function computeNewHighWaterMark(n: number) {
if (n >= MAX_HWM) {
n = MAX_HWM;
} else {
n--;
n |= n >>> 1;
n |= n >>> 2;
n |= n >>> 4;
n |= n >>> 8;
n |= n >>> 16;
n++;
}
return n;
}
function howMuchToRead(n: number, state: ReadableState) {
if (n <= 0 || (state.length === 0 && state.ended)) {
return 0;
}
if (state.objectMode) {
return 1;
}
if (Number.isNaN(n)) {
// Only flow one buffer at a time.
if (state.flowing && state.length) {
return state.buffer.first().length;
}
return state.length;
}
if (n <= state.length) {
return n;
}
return state.ended ? state.length : 0;
}
function onEofChunk(stream: Readable, state: ReadableState) {
if (state.ended) return;
if (state.decoder) {
const chunk = state.decoder.end();
if (chunk && chunk.length) {
state.buffer.push(chunk);
state.length += state.objectMode ? 1 : chunk.length;
}
}
state.ended = true;
if (state.sync) {
emitReadable(stream);
} else {
state.needReadable = false;
state.emittedReadable = true;
emitReadable_(stream);
}
}
function emitReadable(stream: Readable) {
const state = stream._readableState;
state.needReadable = false;
if (!state.emittedReadable) {
state.emittedReadable = true;
queueMicrotask(() => emitReadable_(stream));
}
}
function emitReadable_(stream: Readable) {
const state = stream._readableState;
if (!state.destroyed && !state.errored && (state.length || state.ended)) {
stream.emit("readable");
state.emittedReadable = false;
}
state.needReadable = !state.flowing &&
!state.ended &&
state.length <= state.highWaterMark;
flow(stream);
}
function maybeReadMore(stream: Readable, state: ReadableState) {
if (!state.readingMore && state.constructed) {
state.readingMore = true;
queueMicrotask(() => maybeReadMore_(stream, state));
}
}
function maybeReadMore_(stream: Readable, state: ReadableState) {
while (
!state.reading && !state.ended &&
(state.length < state.highWaterMark ||
(state.flowing && state.length === 0))
) {
const len = state.length;
stream.read(0);
if (len === state.length) {
// Didn't get any data, stop spinning.
break;
}
}
state.readingMore = false;
}
export interface ReadableOptions {
autoDestroy?: boolean;
construct?: () => void;
//TODO(Soremwar)
//Import available encodings
defaultEncoding?: string;
destroy?(
this: Readable,
error: Error | null,
callback: (error: Error | null) => void,
): void;
emitClose?: boolean;
//TODO(Soremwar)
//Import available encodings
encoding?: string;
highWaterMark?: number;
objectMode?: boolean;
read?(this: Readable): void;
}
export class ReadableState {
[kPaused]: boolean | null = null;
awaitDrainWriters: Writable | Set<Writable> | null = null;
buffer = new BufferList();
closed = false;
closeEmitted = false;
constructed: boolean;
decoder: StringDecoder | null = null;
destroyed = false;
emittedReadable = false;
//TODO(Soremwar)
//Import available encodings
encoding: string | null = null;
ended = false;
endEmitted = false;
errored: Error | null = null;
errorEmitted = false;
flowing: boolean | null = null;
highWaterMark: number;
length = 0;
multiAwaitDrain = false;
needReadable = false;
objectMode: boolean;
pipes: Writable[] = [];
readable = true;
readableListening = false;
reading = false;
readingMore = false;
resumeScheduled = false;
sync = true;
emitClose: boolean;
autoDestroy: boolean;
defaultEncoding: string;
constructor(options?: ReadableOptions) {
this.objectMode = !!options?.objectMode;
this.highWaterMark = options?.highWaterMark ??
(this.objectMode ? 16 : 16 * 1024);
if (Number.isInteger(this.highWaterMark) && this.highWaterMark >= 0) {
this.highWaterMark = Math.floor(this.highWaterMark);
} else {
throw new ERR_INVALID_OPT_VALUE("highWaterMark", this.highWaterMark);
}
this.emitClose = options?.emitClose ?? true;
this.autoDestroy = options?.autoDestroy ?? true;
this.defaultEncoding = options?.defaultEncoding || "utf8";
if (options?.encoding) {
this.decoder = new StringDecoder(options.encoding);
this.encoding = options.encoding;
}
this.constructed = true;
}
}
class Readable extends Stream {
_construct?: (cb: (error?: Error) => void) => void;
_readableState: ReadableState;
constructor(options?: ReadableOptions) {
super();
if (options) {
if (typeof options.read === "function") {
this._read = options.read;
}
if (typeof options.destroy === "function") {
this._destroy = options.destroy;
}
if (typeof options.construct === "function") {
this._construct = options.construct;
}
}
this._readableState = new ReadableState(options);
construct(this, () => {
maybeReadMore(this, this._readableState);
});
}
static from(
// deno-lint-ignore no-explicit-any
iterable: Iterable<any> | AsyncIterable<any>,
opts?: ReadableOptions,
): Readable {
return streamFrom(iterable, opts);
}
static ReadableState = ReadableState;
static _fromList = fromList;
// You can override either this method, or the async _read(n) below.
read(n?: number) {
// Same as parseInt(undefined, 10), however V8 7.3 performance regressed
// in this scenario, so we are doing it manually.
if (n === undefined) {
n = NaN;
}
const state = this._readableState;
const nOrig = n;
if (n > state.highWaterMark) {
state.highWaterMark = computeNewHighWaterMark(n);
}
if (n !== 0) {
state.emittedReadable = false;
}
if (
n === 0 &&
state.needReadable &&
((state.highWaterMark !== 0
? state.length >= state.highWaterMark
: state.length > 0) ||
state.ended)
) {
if (state.length === 0 && state.ended) {
endReadable(this);
} else {
emitReadable(this);
}
return null;
}
n = howMuchToRead(n, state);
if (n === 0 && state.ended) {
if (state.length === 0) {
endReadable(this);
}
return null;
}
let doRead = state.needReadable;
if (
state.length === 0 || state.length - (n as number) < state.highWaterMark
) {
doRead = true;
}
if (
state.ended || state.reading || state.destroyed || state.errored ||
!state.constructed
) {
doRead = false;
} else if (doRead) {
state.reading = true;
state.sync = true;
if (state.length === 0) {
state.needReadable = true;
}
this._read();
state.sync = false;
if (!state.reading) {
n = howMuchToRead(nOrig, state);
}
}
let ret;
if ((n as number) > 0) {
ret = fromList((n as number), state);
} else {
ret = null;
}
if (ret === null) {
state.needReadable = state.length <= state.highWaterMark;
n = 0;
} else {
state.length -= n as number;
if (state.multiAwaitDrain) {
(state.awaitDrainWriters as Set<Writable>).clear();
} else {
state.awaitDrainWriters = null;
}
}
if (state.length === 0) {
if (!state.ended) {
state.needReadable = true;
}
if (nOrig !== n && state.ended) {
endReadable(this);
}
}
if (ret !== null) {
this.emit("data", ret);
}
return ret;
}
_read() {
throw new ERR_METHOD_NOT_IMPLEMENTED("_read()");
}
//TODO(Soremwar)
//Should be duplex
pipe<T extends Writable>(dest: T, pipeOpts?: { end?: boolean }): T {
// deno-lint-ignore no-this-alias
const src = this;
const state = this._readableState;
if (state.pipes.length === 1) {
if (!state.multiAwaitDrain) {
state.multiAwaitDrain = true;
state.awaitDrainWriters = new Set(
state.awaitDrainWriters ? [state.awaitDrainWriters as Writable] : [],
);
}
}
state.pipes.push(dest);
const doEnd = (!pipeOpts || pipeOpts.end !== false);
//TODO(Soremwar)
//Part of doEnd condition
//In node, output/inout are a duplex Stream
// &&
// dest !== stdout &&
// dest !== stderr
const endFn = doEnd ? onend : unpipe;
if (state.endEmitted) {
queueMicrotask(endFn);
} else {
this.once("end", endFn);
}
dest.on("unpipe", onunpipe);
function onunpipe(readable: Readable, unpipeInfo: { hasUnpiped: boolean }) {
if (readable === src) {
if (unpipeInfo && unpipeInfo.hasUnpiped === false) {
unpipeInfo.hasUnpiped = true;
cleanup();
}
}
}
function onend() {
dest.end();
}
let ondrain: () => void;
let cleanedUp = false;
function cleanup() {
dest.removeListener("close", onclose);
dest.removeListener("finish", onfinish);
if (ondrain) {
dest.removeListener("drain", ondrain);
}
dest.removeListener("error", onerror);
dest.removeListener("unpipe", onunpipe);
src.removeListener("end", onend);
src.removeListener("end", unpipe);
src.removeListener("data", ondata);
cleanedUp = true;
if (
ondrain && state.awaitDrainWriters &&
(!dest._writableState || dest._writableState.needDrain)
) {
ondrain();
}
}
this.on("data", ondata);
// deno-lint-ignore no-explicit-any
function ondata(chunk: any) {
const ret = dest.write(chunk);
if (ret === false) {
if (!cleanedUp) {
if (state.pipes.length === 1 && state.pipes[0] === dest) {
state.awaitDrainWriters = dest;
state.multiAwaitDrain = false;
} else if (state.pipes.length > 1 && state.pipes.includes(dest)) {
(state.awaitDrainWriters as Set<Writable>).add(dest);
}
src.pause();
}
if (!ondrain) {
ondrain = pipeOnDrain(src, dest);
dest.on("drain", ondrain);
}
}
}
function onerror(er: Error) {
unpipe();
dest.removeListener("error", onerror);
if (dest.listenerCount("error") === 0) {
//TODO(Soremwar)
//Should be const s = dest._writableState || dest._readableState;
const s = dest._writableState;
if (s && !s.errorEmitted) {
// User incorrectly emitted 'error' directly on the stream.
errorOrDestroyDuplex(dest, er);
} else {
dest.emit("error", er);
}
}
}
prependListener(dest, "error", onerror);
function onclose() {
dest.removeListener("finish", onfinish);
unpipe();
}
dest.once("close", onclose);
function onfinish() {
dest.removeListener("close", onclose);
unpipe();
}
dest.once("finish", onfinish);
function unpipe() {
src.unpipe(dest);
}
dest.emit("pipe", this);
if (!state.flowing) {
this.resume();
}
return dest;
}
isPaused() {
return this._readableState[kPaused] === true ||
this._readableState.flowing === false;
}
//TODO(Soremwar)
//Replace string with encoding types
setEncoding(enc: string) {
const decoder = new StringDecoder(enc);
this._readableState.decoder = decoder;
this._readableState.encoding = this._readableState.decoder.encoding;
const buffer = this._readableState.buffer;
let content = "";
for (const data of buffer) {
content += decoder.write(data as Buffer);
}
buffer.clear();
if (content !== "") {
buffer.push(content);
}
this._readableState.length = content.length;
return this;
}
on(
event: "close" | "end" | "pause" | "readable" | "resume",
listener: () => void,
): this;
// deno-lint-ignore no-explicit-any
on(event: "data", listener: (chunk: any) => void): this;
on(event: "error", listener: (err: Error) => void): this;
// deno-lint-ignore no-explicit-any
on(event: string | symbol, listener: (...args: any[]) => void): this;
on(
ev: string | symbol,
fn:
| (() => void)
// deno-lint-ignore no-explicit-any
| ((chunk: any) => void)
| ((err: Error) => void)
// deno-lint-ignore no-explicit-any
| ((...args: any[]) => void),
) {
const res = super.on.call(this, ev, fn);
const state = this._readableState;
if (ev === "data") {
state.readableListening = this.listenerCount("readable") > 0;
if (state.flowing !== false) {
this.resume();
}
} else if (ev === "readable") {
if (!state.endEmitted && !state.readableListening) {
state.readableListening = state.needReadable = true;
state.flowing = false;
state.emittedReadable = false;
if (state.length) {
emitReadable(this);
} else if (!state.reading) {
queueMicrotask(() => nReadingNextTick(this));
}
}
}
return res;
}
removeListener(
event: "close" | "end" | "pause" | "readable" | "resume",
listener: () => void,
): this;
// deno-lint-ignore no-explicit-any
removeListener(event: "data", listener: (chunk: any) => void): this;
removeListener(event: "error", listener: (err: Error) => void): this;
removeListener(
event: string | symbol,
// deno-lint-ignore no-explicit-any
listener: (...args: any[]) => void,
): this;
removeListener(
ev: string | symbol,
fn:
| (() => void)
// deno-lint-ignore no-explicit-any
| ((chunk: any) => void)
| ((err: Error) => void)
// deno-lint-ignore no-explicit-any
| ((...args: any[]) => void),
) {
const res = super.removeListener.call(this, ev, fn);
if (ev === "readable") {
queueMicrotask(() => updateReadableListening(this));
}
return res;
}
off = this.removeListener;
destroy(err?: Error, cb?: () => void) {
const r = this._readableState;
if (r.destroyed) {
if (typeof cb === "function") {
cb();
}
return this;
}
if (err) {
// Avoid V8 leak, https://github.com/nodejs/node/pull/34103#issuecomment-652002364
err.stack;
if (!r.errored) {
r.errored = err;
}
}
r.destroyed = true;
// If still constructing then defer calling _destroy.
if (!r.constructed) {
this.once(kDestroy, (er: Error) => {
_destroy(this, err || er, cb);
});
} else {
_destroy(this, err, cb);
}
return this;
}
_undestroy() {
const r = this._readableState;
r.constructed = true;
r.closed = false;
r.closeEmitted = false;
r.destroyed = false;
r.errored = null;
r.errorEmitted = false;
r.reading = false;
r.ended = false;
r.endEmitted = false;
}
_destroy(
error: Error | null,
callback: (error?: Error | null) => void,
): void {
callback(error);
}
[captureRejectionSymbol](err: Error) {
this.destroy(err);
}
//TODO(Soremwar)
//Same deal, string => encodings
// deno-lint-ignore no-explicit-any
push(chunk: any, encoding?: string): boolean {
return readableAddChunk(this, chunk, encoding, false);
}
// deno-lint-ignore no-explicit-any
unshift(chunk: any, encoding?: string): boolean {
return readableAddChunk(this, chunk, encoding, true);
}
unpipe(dest?: Writable): this {
const state = this._readableState;
const unpipeInfo = { hasUnpiped: false };
if (state.pipes.length === 0) {
return this;
}
if (!dest) {
// remove all.
const dests = state.pipes;
state.pipes = [];
this.pause();
for (const dest of dests) {
dest.emit("unpipe", this, { hasUnpiped: false });
}
return this;
}
const index = state.pipes.indexOf(dest);
if (index === -1) {
return this;
}
state.pipes.splice(index, 1);
if (state.pipes.length === 0) {
this.pause();
}
dest.emit("unpipe", this, unpipeInfo);
return this;
}
removeAllListeners(
ev:
| "close"
| "data"
| "end"
| "error"
| "pause"
| "readable"
| "resume"
| symbol
| undefined,
) {
const res = super.removeAllListeners(ev);
if (ev === "readable" || ev === undefined) {
queueMicrotask(() => updateReadableListening(this));
}
return res;
}
resume() {
const state = this._readableState;
if (!state.flowing) {
// We flow only if there is no one listening
// for readable, but we still have to call
// resume().
state.flowing = !state.readableListening;
resume(this, state);
}
state[kPaused] = false;
return this;
}
pause() {
if (this._readableState.flowing !== false) {
this._readableState.flowing = false;
this.emit("pause");
}
this._readableState[kPaused] = true;
return this;
}
/** Wrap an old-style stream as the async data source. */
wrap(stream: Stream): this {
const state = this._readableState;
let paused = false;
stream.on("end", () => {
if (state.decoder && !state.ended) {
const chunk = state.decoder.end();
if (chunk && chunk.length) {
this.push(chunk);
}
}
this.push(null);
});
stream.on("data", (chunk) => {
if (state.decoder) {
chunk = state.decoder.write(chunk);
}
if (state.objectMode && (chunk === null || chunk === undefined)) {
return;
} else if (!state.objectMode && (!chunk || !chunk.length)) {
return;
}
const ret = this.push(chunk);
if (!ret) {
paused = true;
// By the time this is triggered, stream will be a readable stream
// deno-lint-ignore ban-ts-comment
// @ts-ignore
stream.pause();
}
});
// TODO(Soremwar)
// There must be a clean way to implement this on TypeScript
// Proxy all the other methods. Important when wrapping filters and duplexes.
for (const i in stream) {
// deno-lint-ignore ban-ts-comment
//@ts-ignore
if (this[i] === undefined && typeof stream[i] === "function") {
// deno-lint-ignore ban-ts-comment
//@ts-ignore
this[i] = function methodWrap(method) {
return function methodWrapReturnFunction() {
// deno-lint-ignore ban-ts-comment
//@ts-ignore
return stream[method].apply(stream);
};
}(i);
}
}
stream.on("error", (err) => {
errorOrDestroy(this, err);
});
stream.on("close", () => {
this.emit("close");
});
stream.on("destroy", () => {
this.emit("destroy");
});
stream.on("pause", () => {
this.emit("pause");
});
stream.on("resume", () => {
this.emit("resume");
});
this._read = () => {
if (paused) {
paused = false;
// By the time this is triggered, stream will be a readable stream
// deno-lint-ignore ban-ts-comment
//@ts-ignore
stream.resume();
}
};
return this;
}
[Symbol.asyncIterator]() {
return createReadableStreamAsyncIterator(this);
}
get readable(): boolean {
return this._readableState?.readable &&
!this._readableState?.destroyed &&
!this._readableState?.errorEmitted &&
!this._readableState?.endEmitted;
}
set readable(val: boolean) {
if (this._readableState) {
this._readableState.readable = val;
}
}
get readableHighWaterMark(): number {
return this._readableState.highWaterMark;
}
get readableBuffer() {
return this._readableState && this._readableState.buffer;
}
get readableFlowing(): boolean | null {
return this._readableState.flowing;
}
set readableFlowing(state: boolean | null) {
if (this._readableState) {
this._readableState.flowing = state;
}
}
get readableLength() {
return this._readableState.length;
}
get readableObjectMode() {
return this._readableState ? this._readableState.objectMode : false;
}
get readableEncoding() {
return this._readableState ? this._readableState.encoding : null;
}
get destroyed() {
if (this._readableState === undefined) {
return false;
}
return this._readableState.destroyed;
}
set destroyed(value: boolean) {
if (!this._readableState) {
return;
}
this._readableState.destroyed = value;
}
get readableEnded() {
return this._readableState ? this._readableState.endEmitted : false;
}
}
Object.defineProperties(Stream, {
_readableState: { enumerable: false },
destroyed: { enumerable: false },
readableBuffer: { enumerable: false },
readableEncoding: { enumerable: false },
readableEnded: { enumerable: false },
readableFlowing: { enumerable: false },
readableHighWaterMark: { enumerable: false },
readableLength: { enumerable: false },
readableObjectMode: { enumerable: false },
});
export default Readable;