cb7fb85842
Changed index.js to add WebSockets to the server Changed index.html to add WebSockets to the client Install ws (web sockets) module
63 lines
1.5 KiB
JavaScript
63 lines
1.5 KiB
JavaScript
'use strict';
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const { tokenChars } = require('./validation');
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/**
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* Parses the `Sec-WebSocket-Protocol` header into a set of subprotocol names.
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*
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* @param {String} header The field value of the header
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* @return {Set} The subprotocol names
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* @public
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*/
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function parse(header) {
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const protocols = new Set();
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let start = -1;
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let end = -1;
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let i = 0;
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for (i; i < header.length; i++) {
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const code = header.charCodeAt(i);
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if (end === -1 && tokenChars[code] === 1) {
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if (start === -1) start = i;
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} else if (
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i !== 0 &&
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(code === 0x20 /* ' ' */ || code === 0x09) /* '\t' */
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) {
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if (end === -1 && start !== -1) end = i;
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} else if (code === 0x2c /* ',' */) {
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if (start === -1) {
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throw new SyntaxError(`Unexpected character at index ${i}`);
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}
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if (end === -1) end = i;
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const protocol = header.slice(start, end);
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if (protocols.has(protocol)) {
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throw new SyntaxError(`The "${protocol}" subprotocol is duplicated`);
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}
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protocols.add(protocol);
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start = end = -1;
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} else {
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throw new SyntaxError(`Unexpected character at index ${i}`);
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}
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}
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if (start === -1 || end !== -1) {
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throw new SyntaxError('Unexpected end of input');
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}
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const protocol = header.slice(start, i);
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if (protocols.has(protocol)) {
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throw new SyntaxError(`The "${protocol}" subprotocol is duplicated`);
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}
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protocols.add(protocol);
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return protocols;
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}
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module.exports = { parse };
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