116 lines
2.2 KiB
JavaScript
116 lines
2.2 KiB
JavaScript
import readline from 'node:readline';
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import net from 'node:net';
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import fs from 'node:fs';
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export class Relay {
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#target_stream = null;
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#socket_server = null;
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#line_buffer_tally = 0;
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constructor(listening_socket, target_socket, line_buffer=[], line_buffer_max_size=1024**2) {
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Object.assign(this, { listening_socket, target_socket, line_buffer, line_buffer_max_size });
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}
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serve() {
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const server = net.createServer((socket) => {
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console.log("socket connected");
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const rli = readline.createInterface({
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input: socket,
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crlfDelay: Infinity
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});
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rli.on('line', (line) => this.log_line(line));
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socket.on('close', () => {
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console.log("socket closed");
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});
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socket.on('error', (err) => {
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console.log("socket error", { err });
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});
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});
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server.on('error', (err) => {
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console.log("server error", { err });
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});
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this.listening_socket.listen(server, () => {
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this.#socket_server = server;
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});
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}
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buffer_line(line) {
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this.#line_buffer_tally += line.length + 1;
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this.line_buffer.push(line); // NOTE: We may of course briefly overshoot here but we are not expecting or caring about huge oneliners for now
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while (this.line_buffer.length && (this.#line_buffer_tally > this.line_buffer_max_size)) {
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const discarded = this.line_buffer.shift();
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this.#line_buffer_tally -= discarded.length + 1;
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console.log({ discarded });
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}
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}
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log_line(line) {
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this.buffer_line(line);
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if (this.#target_stream) {
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this.#flush();
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} else {
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this.#connect_target();
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}
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}
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#connect_target() {
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if (this.#target_stream) {
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return;
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}
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const socket = net.createConnection(this.target_socket.connect_options);
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socket.on('connect', () => {
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this.#target_stream = socket;
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this.#flush();
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});
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socket.on('error', (err) => {
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console.log("target error", { err });
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socket.destroy();
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this.#target_stream = null;
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});
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socket.on('close', () => {
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this.#target_stream = null;
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});
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}
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#flush() {
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while (this.line_buffer.length && this.#target_stream) {
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const line = this.line_buffer[0];
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const ok = this.#target_stream.write(line + '\n');
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if (ok === false) {
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return;
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}
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this.line_buffer.shift();
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}
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}
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} |