27 lines
886 B
TypeScript
27 lines
886 B
TypeScript
const { PACKET_TYPES } = require("./commons")
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export const encodePacket = ({ type, data }, supportsBinary, callback) => {
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console.trace('encodePacket', type, JSON.stringify(data))
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if (data instanceof ArrayBuffer || ArrayBuffer.isView(data)) {
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const buffer = toBuffer(data)
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return callback(encodeBuffer(buffer, supportsBinary))
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}
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// plain string
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return callback(PACKET_TYPES[type] + (data || ""))
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}
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const toBuffer = data => {
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if (Buffer.isBuffer(data)) {
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return data
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} else if (data instanceof ArrayBuffer) {
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return Buffer.from(data)
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} else {
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return Buffer.from(data.buffer, data.byteOffset, data.byteLength)
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}
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}
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// only 'message' packets can contain binary, so the type prefix is not needed
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const encodeBuffer = (data, supportsBinary) => {
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return supportsBinary ? data : "b" + data.toString("base64")
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}
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