
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';
/**
* Calculate data maxRate
* @param {Number} [samplesCount= 10]
* @param {Number} [min= 1000]
* @returns {Function}
*/
function speedometer(samplesCount, min) {
samplesCount = samplesCount || 10;
const bytes = new Array(samplesCount);
const timestamps = new Array(samplesCount);
let head = 0;
let tail = 0;
let firstSampleTS;
min = min !== undefined ? min : 1000;
return function push(chunkLength) {
const now = Date.now();
const startedAt = timestamps[tail];
if (!firstSampleTS) {
firstSampleTS = now;
}
bytes[head] = chunkLength;
timestamps[head] = now;
let i = tail;
let bytesCount = 0;
while (i !== head) {
bytesCount += bytes[i++];
i = i % samplesCount;
}
head = (head + 1) % samplesCount;
if (head === tail) {
tail = (tail + 1) % samplesCount;
}
if (now - firstSampleTS < min) {
return;
}
const passed = startedAt && now - startedAt;
return passed ? Math.round(bytesCount * 1000 / passed) : undefined;
};
}
export default speedometer;