
File name
Commit message
Commit date
File name
Commit message
Commit date
File name
Commit message
Commit date
File name
Commit message
Commit date
File name
Commit message
Commit date
'use strict';
import stream from 'stream';
import utils from '../utils.js';
import throttle from './throttle.js';
import speedometer from './speedometer.js';
const kInternals = Symbol('internals');
class AxiosTransformStream extends stream.Transform{
constructor(options) {
options = utils.toFlatObject(options, {
maxRate: 0,
chunkSize: 64 * 1024,
minChunkSize: 100,
timeWindow: 500,
ticksRate: 2,
samplesCount: 15
}, null, (prop, source) => {
return !utils.isUndefined(source[prop]);
});
super({
readableHighWaterMark: options.chunkSize
});
const self = this;
const internals = this[kInternals] = {
length: options.length,
timeWindow: options.timeWindow,
ticksRate: options.ticksRate,
chunkSize: options.chunkSize,
maxRate: options.maxRate,
minChunkSize: options.minChunkSize,
bytesSeen: 0,
isCaptured: false,
notifiedBytesLoaded: 0,
ts: Date.now(),
bytes: 0,
onReadCallback: null
};
const _speedometer = speedometer(internals.ticksRate * options.samplesCount, internals.timeWindow);
this.on('newListener', event => {
if (event === 'progress') {
if (!internals.isCaptured) {
internals.isCaptured = true;
}
}
});
let bytesNotified = 0;
internals.updateProgress = throttle(function throttledHandler() {
const totalBytes = internals.length;
const bytesTransferred = internals.bytesSeen;
const progressBytes = bytesTransferred - bytesNotified;
if (!progressBytes || self.destroyed) return;
const rate = _speedometer(progressBytes);
bytesNotified = bytesTransferred;
process.nextTick(() => {
self.emit('progress', {
'loaded': bytesTransferred,
'total': totalBytes,
'progress': totalBytes ? (bytesTransferred / totalBytes) : undefined,
'bytes': progressBytes,
'rate': rate ? rate : undefined,
'estimated': rate && totalBytes && bytesTransferred <= totalBytes ?
(totalBytes - bytesTransferred) / rate : undefined
});
});
}, internals.ticksRate);
const onFinish = () => {
internals.updateProgress(true);
};
this.once('end', onFinish);
this.once('error', onFinish);
}
_read(size) {
const internals = this[kInternals];
if (internals.onReadCallback) {
internals.onReadCallback();
}
return super._read(size);
}
_transform(chunk, encoding, callback) {
const self = this;
const internals = this[kInternals];
const maxRate = internals.maxRate;
const readableHighWaterMark = this.readableHighWaterMark;
const timeWindow = internals.timeWindow;
const divider = 1000 / timeWindow;
const bytesThreshold = (maxRate / divider);
const minChunkSize = internals.minChunkSize !== false ? Math.max(internals.minChunkSize, bytesThreshold * 0.01) : 0;
function pushChunk(_chunk, _callback) {
const bytes = Buffer.byteLength(_chunk);
internals.bytesSeen += bytes;
internals.bytes += bytes;
if (internals.isCaptured) {
internals.updateProgress();
}
if (self.push(_chunk)) {
process.nextTick(_callback);
} else {
internals.onReadCallback = () => {
internals.onReadCallback = null;
process.nextTick(_callback);
};
}
}
const transformChunk = (_chunk, _callback) => {
const chunkSize = Buffer.byteLength(_chunk);
let chunkRemainder = null;
let maxChunkSize = readableHighWaterMark;
let bytesLeft;
let passed = 0;
if (maxRate) {
const now = Date.now();
if (!internals.ts || (passed = (now - internals.ts)) >= timeWindow) {
internals.ts = now;
bytesLeft = bytesThreshold - internals.bytes;
internals.bytes = bytesLeft < 0 ? -bytesLeft : 0;
passed = 0;
}
bytesLeft = bytesThreshold - internals.bytes;
}
if (maxRate) {
if (bytesLeft <= 0) {
// next time window
return setTimeout(() => {
_callback(null, _chunk);
}, timeWindow - passed);
}
if (bytesLeft < maxChunkSize) {
maxChunkSize = bytesLeft;
}
}
if (maxChunkSize && chunkSize > maxChunkSize && (chunkSize - maxChunkSize) > minChunkSize) {
chunkRemainder = _chunk.subarray(maxChunkSize);
_chunk = _chunk.subarray(0, maxChunkSize);
}
pushChunk(_chunk, chunkRemainder ? () => {
process.nextTick(_callback, null, chunkRemainder);
} : _callback);
};
transformChunk(chunk, function transformNextChunk(err, _chunk) {
if (err) {
return callback(err);
}
if (_chunk) {
transformChunk(_chunk, transformNextChunk);
} else {
callback(null);
}
});
}
setLength(length) {
this[kInternals].length = +length;
return this;
}
}
export default AxiosTransformStream;