iot-backend/software/flow/node_modules/engine.io-parser/build/esm/decodePacket.js

48 lines
1.4 KiB
JavaScript

import { ERROR_PACKET, PACKET_TYPES_REVERSE } from "./commons.js";
const decodePacket = (encodedPacket, binaryType) => {
if (typeof encodedPacket !== "string") {
return {
type: "message",
data: mapBinary(encodedPacket, binaryType)
};
}
const type = encodedPacket.charAt(0);
if (type === "b") {
const buffer = Buffer.from(encodedPacket.substring(1), "base64");
return {
type: "message",
data: mapBinary(buffer, binaryType)
};
}
if (!PACKET_TYPES_REVERSE[type]) {
return ERROR_PACKET;
}
return encodedPacket.length > 1
? {
type: PACKET_TYPES_REVERSE[type],
data: encodedPacket.substring(1)
}
: {
type: PACKET_TYPES_REVERSE[type]
};
};
const mapBinary = (data, binaryType) => {
const isBuffer = Buffer.isBuffer(data);
switch (binaryType) {
case "arraybuffer":
return isBuffer ? toArrayBuffer(data) : data;
case "nodebuffer":
default:
return data; // assuming the data is already a Buffer
}
};
const toArrayBuffer = (buffer) => {
const arrayBuffer = new ArrayBuffer(buffer.length);
const view = new Uint8Array(arrayBuffer);
for (let i = 0; i < buffer.length; i++) {
view[i] = buffer[i];
}
return arrayBuffer;
};
export default decodePacket;