ms/packages/websocket/src/engine.io-client/util.ts

56 lines
1.6 KiB
TypeScript

// import { globalThisShim as globalThis } from "./globalThis.js"
export function pick(obj, ...attr) {
return attr.reduce((acc, k) => {
if (obj.hasOwnProperty(k)) {
acc[k] = obj[k]
}
return acc
}, {})
}
// Keep a reference to the real timeout functions so they can be used when overridden
const NATIVE_SET_TIMEOUT = globalThis.setTimeout
const NATIVE_CLEAR_TIMEOUT = globalThis.clearTimeout
export function installTimerFunctions(obj, opts) {
if (opts.useNativeTimers) {
obj.setTimeoutFn = NATIVE_SET_TIMEOUT.bind(globalThis)
obj.clearTimeoutFn = NATIVE_CLEAR_TIMEOUT.bind(globalThis)
} else {
obj.setTimeoutFn = globalThis.setTimeout.bind(globalThis)
obj.clearTimeoutFn = globalThis.clearTimeout.bind(globalThis)
}
}
// base64 encoded buffers are about 33% bigger (https://en.wikipedia.org/wiki/Base64)
const BASE64_OVERHEAD = 1.33
// we could also have used `new Blob([obj]).size`, but it isn't supported in IE9
export function byteLength(obj) {
if (typeof obj === "string") {
return utf8Length(obj)
}
// arraybuffer or blob
return Math.ceil((obj.byteLength || obj.size) * BASE64_OVERHEAD)
}
function utf8Length(str) {
let c = 0,
length = 0
for (let i = 0, l = str.length; i < l; i++) {
c = str.charCodeAt(i)
if (c < 0x80) {
length += 1
} else if (c < 0x800) {
length += 2
} else if (c < 0xd800 || c >= 0xe000) {
length += 3
} else {
i++
length += 4
}
}
return length
}